Trial Outcomes & Findings for Intrathecal Paracetamol Before Spinal Anaesthesia With Chloroprocaine HCl 1% for Short Knee Procedures (NCT NCT03428230)

Results Overview

The study primary efficacy measures will be the VAS scores at each predefined time-point after the anaesthetic intrathecal injection until eligibility for home discharge ( VAS scale is 0-100 mm, where 0 is no pain and 100 is maximum pain)

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

60 participants

Primary outcome timeframe

Pain intensity at rest evaluated using a 0-100 mm VAS at baseline (within 30 min before NIMP IT injection, 0 h), 1, 1.25, 1.5, 1.75, 2 h after NIMP IT injection, then every 30 min after NIMP IT injection until eligibility for home discharge.

Results posted on

2021-06-24

Participant Flow

Participant milestones

Participant milestones
Measure	30 mg Paracetamol 3% (1 mL) 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Overall Study STARTED	15	15	15	15
Overall Study COMPLETED	15	15	15	15
Overall Study NOT COMPLETED	0	0	0	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Intrathecal Paracetamol Before Spinal Anaesthesia With Chloroprocaine HCl 1% for Short Knee Procedures

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Total n=60 Participants Total of all reporting groups
Age, Continuous	46.1 years STANDARD_DEVIATION 10.9 • n=5 Participants	39.7 years STANDARD_DEVIATION 15.5 • n=7 Participants	40.1 years STANDARD_DEVIATION 12.8 • n=5 Participants	45.5 years STANDARD_DEVIATION 13.6 • n=4 Participants	42.85 years STANDARD_DEVIATION 13.2 • n=21 Participants
Sex: Female, Male Female	2 Participants n=5 Participants	2 Participants n=7 Participants	2 Participants n=5 Participants	2 Participants n=4 Participants	8 Participants n=21 Participants
Sex: Female, Male Male	13 Participants n=5 Participants	13 Participants n=7 Participants	13 Participants n=5 Participants	13 Participants n=4 Participants	52 Participants n=21 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants
Race (NIH/OMB) Asian	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants
Race (NIH/OMB) Black or African American	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants
Race (NIH/OMB) White	15 Participants n=5 Participants	15 Participants n=7 Participants	15 Participants n=5 Participants	15 Participants n=4 Participants	60 Participants n=21 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants
Region of Enrollment Switzerland	15 participants n=5 Participants	15 participants n=7 Participants	15 participants n=5 Participants	15 participants n=4 Participants	15 participants n=21 Participants

PRIMARY outcome

Timeframe: Pain intensity at rest evaluated using a 0-100 mm VAS at baseline (within 30 min before NIMP IT injection, 0 h), 1, 1.25, 1.5, 1.75, 2 h after NIMP IT injection, then every 30 min after NIMP IT injection until eligibility for home discharge.

The study primary efficacy measures will be the VAS scores at each predefined time-point after the anaesthetic intrathecal injection until eligibility for home discharge ( VAS scale is 0-100 mm, where 0 is no pain and 100 is maximum pain)

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Pain Intensity at Rest Evaluated Using a 0-100 mm VAS 4 hours after NIMP	6.8 score on a scale Standard Deviation 8.3	13.3 score on a scale Standard Deviation 18.1	15.3 score on a scale Standard Deviation 19.1	0 score on a scale Standard Deviation 0
Pain Intensity at Rest Evaluated Using a 0-100 mm VAS baseline	9.6 score on a scale Standard Deviation 20	16.9 score on a scale Standard Deviation 17.4	18.4 score on a scale Standard Deviation 26.4	8.1 score on a scale Standard Deviation 14.8
Pain Intensity at Rest Evaluated Using a 0-100 mm VAS 1 hour after NIMP	0.1 score on a scale Standard Deviation 0.3	0.1 score on a scale Standard Deviation 0.5	3.4 score on a scale Standard Deviation 11.5	0 score on a scale Standard Deviation 0
Pain Intensity at Rest Evaluated Using a 0-100 mm VAS 1.25 hour after NIMP	4.6 score on a scale Standard Deviation 11.4	1.9 score on a scale Standard Deviation 5.1	6.2 score on a scale Standard Deviation 13.7	0.6 score on a scale Standard Deviation 1.3
Pain Intensity at Rest Evaluated Using a 0-100 mm VAS 1.50 hour after NIMP	5.9 score on a scale Standard Deviation 13.2	4.5 score on a scale Standard Deviation 10.2	16.4 score on a scale Standard Deviation 23.6	1.2 score on a scale Standard Deviation 2.1
Pain Intensity at Rest Evaluated Using a 0-100 mm VAS 1.75 hour after NIMP	9.5 score on a scale Standard Deviation 16.5	15.1 score on a scale Standard Deviation 16.3	21.4 score on a scale Standard Deviation 24.3	3.6 score on a scale Standard Deviation 6.1
Pain Intensity at Rest Evaluated Using a 0-100 mm VAS 2 hours after NIMP	14.1 score on a scale Standard Deviation 24.6	17.8 score on a scale Standard Deviation 19	22.8 score on a scale Standard Deviation 23.2	3.9 score on a scale Standard Deviation 8.7
Pain Intensity at Rest Evaluated Using a 0-100 mm VAS 2.5 hours after NIMP	16.9 score on a scale Standard Deviation 22.8	8.7 score on a scale Standard Deviation 7.1	14.7 score on a scale Standard Deviation 15.8	7.2 score on a scale Standard Deviation 8.2
Pain Intensity at Rest Evaluated Using a 0-100 mm VAS 3 hours after NIMP	21 score on a scale Standard Deviation 27.7	9.6 score on a scale Standard Deviation 12.8	7.3 score on a scale Standard Deviation 13	10.4 score on a scale Standard Deviation 15.4
Pain Intensity at Rest Evaluated Using a 0-100 mm VAS 3.5 hours after NIMP	19.7 score on a scale Standard Deviation 21.4	6.8 score on a scale Standard Deviation 11.4	14.2 score on a scale Standard Deviation 25.7	11.4 score on a scale Standard Deviation 16.8
Pain Intensity at Rest Evaluated Using a 0-100 mm VAS 4.5 hours after NIMP	2.5 score on a scale Standard Deviation 3.5	0 score on a scale Standard Deviation 0	2 score on a scale Standard Deviation 2.6	0 score on a scale Standard Deviation 0
Pain Intensity at Rest Evaluated Using a 0-100 mm VAS before discharge	3.7 score on a scale Standard Deviation 4.7	4.1 score on a scale Standard Deviation 5.6	2.9 score on a scale Standard Deviation 4.5	11.3 score on a scale Standard Deviation 7.7

SECONDARY outcome

Timeframe: Up to 4 hours after injection

AUC t1-t2 is defined as the area under the pain intensity curve at the specified time-intervals

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Pain at Rest AUCt1-t2 AUC 0-4 hours	34.6 score on a scale*h Standard Deviation 29.6	26 score on a scale*h Standard Deviation 10.9	92.2 score on a scale*h Standard Deviation 69.4	49.7 score on a scale*h Standard Deviation 21.7
Pain at Rest AUCt1-t2 AUC 0-2 hours	13 score on a scale*h Standard Deviation 13	14.8 score on a scale*h Standard Deviation 12.5	26.4 score on a scale*h Standard Deviation 30.1	4.4 score on a scale*h Standard Deviation 7.1

SECONDARY outcome

Timeframe: Up to 24 hours after injection

AUClast is defined as the area under the pain intensity curve from 0 h up to the last assessment time

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Pain at Rest AUClast	34 score on a scale*h Standard Deviation 41.3	24.7 score on a scale*h Standard Deviation 15.7	42 score on a scale*h Standard Deviation 50.3	15.7 score on a scale*h Standard Deviation 23.3

SECONDARY outcome

Timeframe: Up to 24 hours after surgery

Population: Nine (9) patients in D1, 10 in D2, 8 in D3 and 14 in P treatment group did not require postoperative analgesia and were censored in the time to first post-operative analgesia analysis

Postoperatively, patients will be administered an analgesic as needed. Post-operative analgesia could include Ketorolac i.v. \[Toradol\] 30 mg (level 1 analgesia) and/or Tramadol i.v. 1 mg/kg (level 2 analgesia). The administered analgesic (level 1 or 2), analgesic dose and intake frequency will be decided according to the reported surgery-related pain intensity. Post-operatively, patients were administered an analgesic, as needed. Post-operative analgesia could include Ketorolac i.v. \[Toradol\] 30 mg (level 1 analgesia) and/or Tramadol i.v. 1 mg/kg (level 2 analgesia).

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=11 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=8 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=14 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=1 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Time to First Postoperative Analgesia (Level 1 or 2) 0-2 hours	5 Participants	3 Participants	7 Participants	0 Participants
Time to First Postoperative Analgesia (Level 1 or 2) 0-4 hours	6 Participants	5 Participants	7 Participants	1 Participants

SECONDARY outcome

Timeframe: from surgery day to 24 hours after surgery

Partecipants to received Ketorolac i.v. \[Toradol\] 30 mg administration (level 1 analgesia)

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Partecipants to Received Level 1 Analgesia	6 Participants	5 Participants	7 Participants	1 Participants

SECONDARY outcome

Timeframe: from surgery day to 24 hours after surgery

Partecipants received Tramadol i.v. 1 mg/kg administration (level 2 analgesia)

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Partecipants Received Level 2 Analgesia	2 Participants	0 Participants	4 Participants	0 Participants

SECONDARY outcome

Timeframe: From surgery day to 24 hours after surgery

Total number of partecipants receiving Ketorolac i.v. \[Toradol\] 30 mg

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Total Number of Partecipants Receiving Analgesic 1	6 Participants	5 Participants	7 Participants	1 Participants

SECONDARY outcome

Timeframe: from surgery day to 24 hours after surgery

Total Number of Partecipants Receiving Tramadol i.v. 1 mg/kg

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Total Number of Partecipants Receiving Analgesic 2	2 Participants	0 Participants	4 Participants	0 Participants

SECONDARY outcome

Timeframe: Form surgery day to 2 hours after surgery end

Percentage of patients requiring analgesia (level 1 or level 2) in the first 2 h after surgery end

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Percentage of Patients Requiring Analgesia in the First 2 h After Surgery End	5 Participants	3 Participants	7 Participants	0 Participants

SECONDARY outcome

Timeframe: from surgery day to 4 hours after surgery end

Percentage of patients requiring analgesia (level 1 or level 2) in the first 4 h after surgery end

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Percentage of Patients Requiring Analgesia in the First 4 h After Surgery End	6 Participants	5 Participants	7 Participants	1 Participants

SECONDARY outcome

Timeframe: from surgery day to 24 hours after surgery

Percentage of patients requiring analgesia (level 1 or level 2) from surgery end until eligibility for home discharge

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=14 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Percentage of Patients Requiring Analgesia From Surgery End Until Eligibility for Discharge	6 Participants	5 Participants	7 Participants	1 Participants

SECONDARY outcome

Timeframe: from surgery day to 24 hours after surgery

Percentage of patients requiring level 1 analgesia from surgery end until eligibility for home discharge

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Percentage of Patients Requiring Level 1 Analgesia From Surgery End Until Eligibility for Discharge	6 Participants	5 Participants	7 Participants	1 Participants

SECONDARY outcome

Timeframe: from surgery day to 24 hours after surgery

Percentage of Patients Requiring Level 2 Analgesia From Surgery End Until Eligibility for Home Discharge

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Percentage of Patients Requiring Level 2 Analgesia From Surgery End Until Eligibility for Discharge	2 Participants	0 Participants	4 Participants	0 Participants

SECONDARY outcome

Timeframe: from surgery day to 24 hours after surgery

Percentage of patients requiring supplementary analgesia, other than the planned level 1 or 2 analgesia

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Percentage of Patients Requiring Supplementary Analgesia, Other Than the Planned Level 1 or 2 Analgesia level 1	6 participants	5 participants	7 participants	1 participants
Percentage of Patients Requiring Supplementary Analgesia, Other Than the Planned Level 1 or 2 Analgesia level 2	2 participants	0 participants	4 participants	0 participants

SECONDARY outcome

Timeframe: from surgery day to 1 hour after injection

Percentage of patients requiring rescue anaesthesia

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Percentage of Patients Requiring Rescue Anaesthesia	14 Participants	15 Participants	15 Participants	14 Participants

SECONDARY outcome

Timeframe: Up to 20 minutes after injection

Spinal block/Readiness for surgery is defined as the presence of an adequate motor block (Bromage's score ≥ 2) and loss of Pinprick sensation, according to the Investigator's opinion. Time to readiness for surgery is defined as the time from the spinal injection (time 0 h) to achievement of readiness for surgery.

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Time to Onset of Spinal Block (i.e. Time to Readiness for Surgery)	5 minutes Interval 2.0 to 5.0	5 minutes Interval 3.0 to 5.0	2 minutes Interval 1.0 to 5.0	5 minutes Interval 2.0 to 5.0

SECONDARY outcome

Timeframe: Intraoperative

Maximum level of sensory block

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Maximum Sensory Block T1	0 Participants	0 Participants	0 Participants	0 Participants
Maximum Sensory Block T5	0 Participants	1 Participants	1 Participants	1 Participants
Maximum Sensory Block T6	1 Participants	1 Participants	1 Participants	1 Participants
Maximum Sensory Block T7	0 Participants	1 Participants	0 Participants	0 Participants
Maximum Sensory Block L2	0 Participants	0 Participants	0 Participants	0 Participants
Maximum Sensory Block L3	0 Participants	0 Participants	0 Participants	0 Participants
Maximum Sensory Block T2	1 Participants	0 Participants	0 Participants	0 Participants
Maximum Sensory Block T3	0 Participants	0 Participants	0 Participants	0 Participants
Maximum Sensory Block T4	0 Participants	0 Participants	1 Participants	1 Participants
Maximum Sensory Block T8	7 Participants	0 Participants	6 Participants	6 Participants
Maximum Sensory Block T9	0 Participants	3 Participants	2 Participants	0 Participants
Maximum Sensory Block T10	3 Participants	5 Participants	1 Participants	4 Participants
Maximum Sensory Block T11	2 Participants	3 Participants	2 Participants	1 Participants
Maximum Sensory Block T12	0 Participants	1 Participants	0 Participants	1 Participants
Maximum Sensory Block L1	1 Participants	0 Participants	1 Participants	0 Participants
Maximum Sensory Block L4	0 Participants	0 Participants	0 Participants	0 Participants
Maximum Sensory Block L5	0 Participants	0 Participants	0 Participants	0 Participants
Maximum Sensory Block S1	0 Participants	0 Participants	0 Participants	0 Participants
Maximum Sensory Block S2	0 Participants	0 Participants	0 Participants	0 Participants
Maximum Sensory Block S3	0 Participants	0 Participants	0 Participants	0 Participants
Maximum Sensory Block S4	0 Participants	0 Participants	0 Participants	0 Participants
Maximum Sensory Block S5	0 Participants	0 Participants	0 Participants	0 Participants

SECONDARY outcome

Timeframe: Intraoperative

Time to maximum level of sensory block (bilateral Pinprick test using a 20-G hypodermic needle)

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Time to Sensory Block	10 minutes Interval 10.0 to 12.0	10 minutes Interval 8.0 to 14.0	10 minutes Interval 5.0 to 10.0	10 minutes Interval 6.0 to 15.0

SECONDARY outcome

Timeframe: Up to 4 hours after injection

Time period from spinal injection to the complete regression of sensory block to S1.

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Time to Regression of Spinal Block	100 minutes Interval 85.0 to 112.0	100 minutes Interval 78.0 to 125.0	90 minutes Interval 76.0 to 95.0	95 minutes Interval 89.0 to 115.0

SECONDARY outcome

Timeframe: Up to 24 hours after injection

Time to unassisted ambulation

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Time to Ambulation	139 minutes Interval 120.0 to 180.0	115 minutes Interval 65.0 to 150.0	125 minutes Interval 95.0 to 170.0	125 minutes Interval 120.0 to 165.0

SECONDARY outcome

Timeframe: Up to 24 hours after injection

Time to first spontaneous urine voiding

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Time to First Urine	155 minutes Interval 122.0 to 220.0	140 minutes Interval 87.0 to 205.0	145 minutes Interval 100.0 to 177.0	150 minutes Interval 125.0 to 170.0

SECONDARY outcome

Timeframe: Up to 24 hours after injection

Time to eligibility for home discharge

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Time to Eligibility for Discharge	170 minutes Interval 145.0 to 230.0	165 minutes Interval 132.0 to 195.0	170 minutes Interval 135.0 to 200.0	168 minutes Interval 145.0 to 190.0

OTHER_PRE_SPECIFIED outcome

Timeframe: From anaesthetic intrathecal injection up to day 7±1 (i.e. 6±1 days after analgesic/anaesthetic IT injection and surgery)

Number of Participants with Neurological Complications Including TNS at 24 h post-dose and at day 7±1

Outcome measures

Outcome measures
Measure	30 mg Paracetamol 3% (1 mL) n=15 Participants 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 Participants 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 Participants 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 Participants Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Number of Participants With Neurological Complications Including TNS	0 Participants	0 Participants	0 Participants	0 Participants

Adverse Events

30 mg Paracetamol 3% (1 mL)

Serious events: 0 serious events

Other events: 3 other events

Deaths: 0 deaths

60 mg Paracetamol 3% (2 mL)

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

90 mg Paracetamol 3% (3 mL)

Serious events: 0 serious events

Other events: 4 other events

Deaths: 0 deaths

Placebo, 0.9% Saline Solution

Serious events: 0 serious events

Other events: 3 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure	30 mg Paracetamol 3% (1 mL) n=15 participants at risk 30 mg Paracetamol 3% (1 mL), solution for injection, single dose by intrathecal injection (IT) 30 mg Paracetamol 3% (1 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injection will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	60 mg Paracetamol 3% (2 mL) n=15 participants at risk 60 mg Paracetamol 3% (2 mL), solution for injection, single dose by intrathecal injection (IT) 60 mg Paracetamol 3% (2 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	90 mg Paracetamol 3% (3 mL) n=15 participants at risk 90 mg Paracetamol 3% (3 mL), solution for injection, single dose by intrathecal injection (IT) 90 mg Paracetamol 3% (3 mL): Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Paracetamol followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Paracetamol will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.	Placebo, 0.9% Saline Solution n=15 participants at risk Placebo, 0.9% saline solution (1 mL, 2 mL or 3 mL), solution for injection, single dose by intrathecal injection (IT) Placebo, 0.9% saline solution: Single administration by intrathecal injection just before spinal anaesthesia. The injections will be performed according to the hospital procedures. For the intrathecal injection of Placebo followed by the intrathecal injection of the anaesthetic, two needles will be used: one introducer needle, which will serve to introduce the second needle through the skin, plus one intrathecal Pencil point needle (27-G or 25-Gauge or Reganesth or Nizell needle) to which the first syringe containing Placebo will be attached first, followed by the second syringe with the anaesthetic. In this way only one intrathecal puncture will be performed. Lumbar puncture will be done according to the standard hospital procedures. NIMP: Chloroprocaine HCl 1% (10 mg/mL), solution for injection: Immediately after intrathecal administration of the Paracetamol dose or Placebo, all patients will receive a single intrathecal dose of Chloroprocaine HCl 1% according to the Summary of Product Characteristics indications. Time interval between the 2 administrations should not exceed 2 min.
Nervous system disorders headache	20.0% 3/15 • Number of events 3 • Adverse events throughout the study 48 hours	0.00% 0/15 • Adverse events throughout the study 48 hours	6.7% 1/15 • Number of events 1 • Adverse events throughout the study 48 hours	6.7% 1/15 • Number of events 1 • Adverse events throughout the study 48 hours
Vascular disorders hypotension	0.00% 0/15 • Adverse events throughout the study 48 hours	0.00% 0/15 • Adverse events throughout the study 48 hours	13.3% 2/15 • Number of events 2 • Adverse events throughout the study 48 hours	6.7% 1/15 • Number of events 1 • Adverse events throughout the study 48 hours
Cardiac disorders bradycardia	0.00% 0/15 • Adverse events throughout the study 48 hours	0.00% 0/15 • Adverse events throughout the study 48 hours	6.7% 1/15 • Number of events 1 • Adverse events throughout the study 48 hours	6.7% 1/15 • Number of events 1 • Adverse events throughout the study 48 hours

Additional Information

Dr.Elisabetta Donati, Corporate Director Scientific Affairs

Sintetica SA

Phone: +41.91.640.42.50

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place