Trial Outcomes & Findings for Effect of a Sciatic Block (SNB) Combined With a Continuous Femoral Block (CFNB) on Pain Scores After Knee Arthroplasty (NCT NCT01337115)

Results Overview

Pain scores measured by Visual Analogue Score (VAS) scale at 15-30min after Post anesthesia care unit (PACU) arrival VAS is a 100mm scale to measure pain. 0mm - no pain 100mm - worst possible pain

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

50 participants

Primary outcome timeframe

15-30 min after arrival on post anesthesia care unit (PACU)

Results posted on

2012-06-19

Participant Flow

April 2011-February 2012. Consecutive patients for total knee arthroplasty at Orthopedic Department, Centro Hospitalar do Porto

Patients were excluded before randomization if refuse, could not use Visual Analogue Scale (VAS) scale, had contraindications for any of the components of the anesthesia protocol or, anesthesiologist was not expert in peripheral blocks

Participant milestones

Participant milestones
Measure	Continuous Femoral Nerve Block (CFNB) A continuous femoral nerve block is performed for peri-operative analgesia and a bolus of 30 ml of ropivacaine 0.375% is injected before surgery starts. An infusion of 8ml/h of ropivacaine 0.2% is started in PACU and maintained for 48h	Single Shot Sciatic Nerve Block (SNB) A single shot sciatic nerve block is performed before surgery with 25ml of 0.2% ropivacaine in addition to the continuous femoral nerve block performed in the control group
Overall Study STARTED	25	25
Overall Study COMPLETED	23	25
Overall Study NOT COMPLETED	2	0

Reasons for withdrawal

Reasons for withdrawal
Measure	Continuous Femoral Nerve Block (CFNB) A continuous femoral nerve block is performed for peri-operative analgesia and a bolus of 30 ml of ropivacaine 0.375% is injected before surgery starts. An infusion of 8ml/h of ropivacaine 0.2% is started in PACU and maintained for 48h	Single Shot Sciatic Nerve Block (SNB) A single shot sciatic nerve block is performed before surgery with 25ml of 0.2% ropivacaine in addition to the continuous femoral nerve block performed in the control group
Overall Study Protocol Violation	2	0

Baseline Characteristics

Effect of a Sciatic Block (SNB) Combined With a Continuous Femoral Block (CFNB) on Pain Scores After Knee Arthroplasty

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Continuous Femoral Nerve Block (CFNB) n=25 Participants A continuous femoral nerve block is performed for peri-operative analgesia and a bolus of 30 ml of ropivacaine 0.375% is injected before surgery starts. An infusion of 8ml/h of ropivacaine 0.2% is started in PACU and maintained for 48h	Single Shot Sciatic Nerve Block (SNB) n=25 Participants A single shot sciatic nerve block is performed before surgery with 25ml of 0.2% ropivacaine in addition to the continuous femoral nerve block performed in the control group	Total n=50 Participants Total of all reporting groups
Age, Categorical <=18 years	0 Participants n=93 Participants	0 Participants n=4 Participants	0 Participants n=27 Participants
Age, Categorical Between 18 and 65 years	10 Participants n=93 Participants	15 Participants n=4 Participants	25 Participants n=27 Participants
Age, Categorical >=65 years	15 Participants n=93 Participants	10 Participants n=4 Participants	25 Participants n=27 Participants
Age Continuous	68.16 years STANDARD_DEVIATION 9.83 • n=93 Participants	65.44 years STANDARD_DEVIATION 8.93 • n=4 Participants	66.8 years STANDARD_DEVIATION 9.4 • n=27 Participants
Sex: Female, Male Female	20 Participants n=93 Participants	16 Participants n=4 Participants	36 Participants n=27 Participants
Sex: Female, Male Male	5 Participants n=93 Participants	9 Participants n=4 Participants	14 Participants n=27 Participants
Region of Enrollment Portugal	25 participants n=93 Participants	25 participants n=4 Participants	50 participants n=27 Participants

PRIMARY outcome

Timeframe: 15-30 min after arrival on post anesthesia care unit (PACU)

Population: Participants were analyzed in an Intention to treat (ITT) manner. All randomized subjects (25 in each arm) completed the protocol so all were included for analysis as planned.

Pain scores measured by Visual Analogue Score (VAS) scale at 15-30min after Post anesthesia care unit (PACU) arrival VAS is a 100mm scale to measure pain. 0mm - no pain 100mm - worst possible pain

Outcome measures

Outcome measures
Measure	Continuous Femoral Nerve Block (CFNB) n=25 Participants A continuous femoral nerve block is performed for peri-operative analgesia and a bolus of 30 ml of ropivacaine 0.375% is injected before surgery starts. An infusion of 8ml/h of ropivacaine 0.2% is started in PACU and maintained for 48h	Single Shot Sciatic Nerve Block (SNB) n=25 Participants A single shot sciatic nerve block is performed before surgery with 25ml of 0.2% ropivacaine in addition to the continuous femoral nerve block performed in the control group
Visual Analogue Scores (VAS) - Pain Scores Measured in mm (0-100)	59.4 units on a scale Standard Deviation 27.2	30.2 units on a scale Standard Deviation 30.5

PRIMARY outcome

Timeframe: 12h after surgery

Population: All 25 patients in each arm completed the protocol. Analysis was made in an ITT manner.

VAS pain scores are measured by blinded investigators 12h after surgery . VAS scale: 0 - no pain 100 - worst possible pain

Outcome measures

Outcome measures
Measure	Continuous Femoral Nerve Block (CFNB) n=25 Participants A continuous femoral nerve block is performed for peri-operative analgesia and a bolus of 30 ml of ropivacaine 0.375% is injected before surgery starts. An infusion of 8ml/h of ropivacaine 0.2% is started in PACU and maintained for 48h	Single Shot Sciatic Nerve Block (SNB) n=25 Participants A single shot sciatic nerve block is performed before surgery with 25ml of 0.2% ropivacaine in addition to the continuous femoral nerve block performed in the control group
VAS Results - Pain Measured in mm (0-100)	26.1 units on a scale Standard Deviation 23.8	9.2 units on a scale Standard Deviation 14.8

PRIMARY outcome

Timeframe: 24h after surgery

Population: In the CFNB group 2 patients did not complete the protocol. Analysis was made in an ITT manner and Last Observational Carried Forward (LOCF) was the imputation technique used. In the SNB group, all 25 patients completed the protocol

VAS pain scores are measured by blinded investigators 24h after surgery . VAS scale: 0 - no pain 100 - worst possible pain

Outcome measures

Outcome measures
Measure	Continuous Femoral Nerve Block (CFNB) n=23 Participants A continuous femoral nerve block is performed for peri-operative analgesia and a bolus of 30 ml of ropivacaine 0.375% is injected before surgery starts. An infusion of 8ml/h of ropivacaine 0.2% is started in PACU and maintained for 48h	Single Shot Sciatic Nerve Block (SNB) n=25 Participants A single shot sciatic nerve block is performed before surgery with 25ml of 0.2% ropivacaine in addition to the continuous femoral nerve block performed in the control group
VAS Results - Pain Scores Measured in mm (0-100)	30.13 units on a scale Standard Deviation 24.97	32.68 units on a scale Standard Deviation 24.49

SECONDARY outcome

Timeframe: 1 month after surgery

Population: Analysis was performed on Participants available for telephone contact one month after surgery and was made per protocol.

Satisfaction with the anesthesia technique using a categorical scale with three levels: Bad Reasonable Good/Very Good A Fisher's Exact test is made to asses any differences in the distribution of patients in each arm to each level of the categorical scale

Outcome measures

Outcome measures
Measure	Continuous Femoral Nerve Block (CFNB) n=20 Participants A continuous femoral nerve block is performed for peri-operative analgesia and a bolus of 30 ml of ropivacaine 0.375% is injected before surgery starts. An infusion of 8ml/h of ropivacaine 0.2% is started in PACU and maintained for 48h	Single Shot Sciatic Nerve Block (SNB) n=21 Participants A single shot sciatic nerve block is performed before surgery with 25ml of 0.2% ropivacaine in addition to the continuous femoral nerve block performed in the control group
Satisfaction With Anesthesia Technique in Each Arm of the Study Bad	0 participants	0 participants
Satisfaction With Anesthesia Technique in Each Arm of the Study Reasonable	3 participants	2 participants
Satisfaction With Anesthesia Technique in Each Arm of the Study Good/Very Good	17 participants	11 participants

Adverse Events

Continuous Femoral Nerve Block (CFNB)

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Single Shot Sciatic Nerve Block (SNB)

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr Raul Carvalho

Centro Hospitalar do Porto

Phone: +351226176114

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place