Trial Outcomes & Findings for Ultrasound-guided Axillary Plexus Block - Dose Reduction of Prilocaine (NCT NCT01309360)

Results Overview

The number of outpatients with complete sensory block of all 4 nerves (n.musculocutaneous, n.radialis, n.ulnaris,n.medianus) was registrated in each group.

Recruitment status

COMPLETED

Study phase

PHASE4

Target enrollment

120 participants

Primary outcome timeframe

60 minutes after administration of the local anesthetic

Results posted on

2011-07-12

Participant Flow

Provision of information and inclusion in the study was done in the anesthesia outpatients clinic as part of the standard preoperative preparation.

Outpatients were prematurely dropped out for medical or non-medical reasons. Non-medical reasons:1.recall of the approval by the patient, 2.unavailability of the ultrasound-machine, 3.the planned operation was not carried out. Medical reasons: severe complications like systemic toxicity of the local anesthetic (seizure, cardiac arrest).

Participant milestones

Participant milestones
Measure	Group A : 40ml Prilocaine 1% 40 outpatients : 40ml Prilocaine 1% were administered for axillary plexus block	Group B : 30ml Prilocaine 1% 40 outpatients : 30ml prilocaine 1% were administered for axillary plexus block	Group C : 20ml Prilocaine 1% 40 outpatients : 20ml prilocaine 1% were administered for axillary plexus block
Overall Study STARTED	40	40	40
Overall Study COMPLETED	40	40	40
Overall Study NOT COMPLETED	0	0	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Ultrasound-guided Axillary Plexus Block - Dose Reduction of Prilocaine

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Group A : 40ml Prilocaine 1% n=40 Participants 40 outpatients : 40ml Prilocaine 1% were administered for axillary plexus block	Group B : 30ml Prilocaine 1% n=40 Participants 40 outpatients : 30ml prilocaine 1% were administered for axillary plexus block	Group C : 20ml Prilocaine 1% n=40 Participants 40 outpatients : 20ml prilocaine 1% were administered for axillary plexus block	Total n=120 Participants Total of all reporting groups
Age Continuous	50 years STANDARD_DEVIATION 14 • n=5 Participants	47 years STANDARD_DEVIATION 16 • n=7 Participants	45 years STANDARD_DEVIATION 16 • n=5 Participants	47 years STANDARD_DEVIATION 15 • n=4 Participants
Sex: Female, Male Female	23 Participants n=5 Participants	20 Participants n=7 Participants	24 Participants n=5 Participants	67 Participants n=4 Participants
Sex: Female, Male Male	17 Participants n=5 Participants	20 Participants n=7 Participants	16 Participants n=5 Participants	53 Participants n=4 Participants
percentage of methemoglobin	0.84 percentage of methemoglobin STANDARD_DEVIATION 0.15 • n=5 Participants	0.9 percentage of methemoglobin STANDARD_DEVIATION 0.16 • n=7 Participants	0.86 percentage of methemoglobin STANDARD_DEVIATION 0.17 • n=5 Participants	0.87 percentage of methemoglobin STANDARD_DEVIATION 0.16 • n=4 Participants

PRIMARY outcome

Timeframe: 60 minutes after administration of the local anesthetic

Population: The analysis was per protocol.

The number of outpatients with complete sensory block of all 4 nerves (n.musculocutaneous, n.radialis, n.ulnaris,n.medianus) was registrated in each group.

Outcome measures

Outcome measures
Measure	Group A : 40ml Prilocaine 1% n=40 Participants 40 outpatients : 40ml prilocaine 1% were administered for axillary plexus block	Group B : 30ml Prilocaine 1% n=40 Participants 40 outpatients : 30ml prilocaine 1% were administered for axillary plexus block	Group C : 20ml Prilocaine 1% n=40 Participants 40 outpatients : 20ml prilocaine 1% were administered for axillary plexus block
Number of Participants With Complete Sensory Block	38 participants	39 participants	39 participants

PRIMARY outcome

Timeframe: Within 60 minutes after administration of the local anesthetic

Population: The analysis was per protocol.

To examine the extent of the motor block the manual muscle function test after Vladimir Janda was used. As a complete motor block was defined, when no motion (grade zero after Janda) of muscles innervated by the four blocked nerves (musculocutaneous, median, radial and ulnar nerve) was observed within 60 minutes after administration of the local anesthetic.

Outcome measures

Outcome measures
Measure	Group A : 40ml Prilocaine 1% n=40 Participants 40 outpatients : 40ml prilocaine 1% were administered for axillary plexus block	Group B : 30ml Prilocaine 1% n=40 Participants 40 outpatients : 30ml prilocaine 1% were administered for axillary plexus block	Group C : 20ml Prilocaine 1% n=40 Participants 40 outpatients : 20ml prilocaine 1% were administered for axillary plexus block
Number of Participants With Complete Motor Blocks	38 participants	36 participants	32 participants

PRIMARY outcome

Timeframe: within 60 minutes after administration of the local anesthetic

Population: In some cases the investigators were not able to exactly determine an onset time, so in cases of block failure (supplementation needed) or emergency situations outside this study (onset time not examined). Therefore the number of participants analyzed concerning onset time is lower then the total number of outpatients in each group.

Time from beginning of administration of the local anesthetic until complete sensoric block.

Outcome measures

Outcome measures
Measure	Group A : 40ml Prilocaine 1% n=35 Participants 40 outpatients : 40ml prilocaine 1% were administered for axillary plexus block	Group B : 30ml Prilocaine 1% n=36 Participants 40 outpatients : 30ml prilocaine 1% were administered for axillary plexus block	Group C : 20ml Prilocaine 1% n=36 Participants 40 outpatients : 20ml prilocaine 1% were administered for axillary plexus block
Onset Time.	18 minutes Standard Deviation 7	20 minutes Standard Deviation 8	26 minutes Standard Deviation 10

SECONDARY outcome

Timeframe: 0,1,2,3,4 hours post-dose

Population: Methemoglobin (Met-Hb) levels were measured using spectrophotometry prior to the anesthesia (baseline value) and then hourly after performing the block until a clear decrease became apparent.The mean maximum Met-Hb was estimated in each group.

Concentration of Methemoglobin (Met-Hb) was measured using spectrophotometry prior to the anesthesia (baseline value) and then hourly after performing the block until a clear decrease became apparent. The maximum amount was reached in every case two or three hours after administration of the local anesthetic.

Outcome measures

Outcome measures
Measure	Group A : 40ml Prilocaine 1% n=40 Participants 40 outpatients : 40ml prilocaine 1% were administered for axillary plexus block	Group B : 30ml Prilocaine 1% n=40 Participants 40 outpatients : 30ml prilocaine 1% were administered for axillary plexus block	Group C : 20ml Prilocaine 1% n=40 Participants 40 outpatients : 20ml prilocaine 1% were administered for axillary plexus block
Maximum Concentrations of Methemoglobin	4.7 percentage of methemoglobin Standard Deviation 2.1	3.7 percentage of methemoglobin Standard Deviation 1.3	2.4 percentage of methemoglobin Standard Deviation 0.7

SECONDARY outcome

Timeframe: Outpatients were followed for the duration of hospital stay, an average of six hours.

In groups A, B and C was determined the rate of objective clinical signs of increased Met-Hb-levels : drops in oxygen saturation \<93% using pulseoximetry or lip cyanosis.

Outcome measures

Outcome measures
Measure	Group A : 40ml Prilocaine 1% n=40 Participants 40 outpatients : 40ml prilocaine 1% were administered for axillary plexus block	Group B : 30ml Prilocaine 1% n=40 Participants 40 outpatients : 30ml prilocaine 1% were administered for axillary plexus block	Group C : 20ml Prilocaine 1% n=40 Participants 40 outpatients : 20ml prilocaine 1% were administered for axillary plexus block
Number of Participants With Objective Adverse Events as a Measure of Safety and Tolerability	13 participants	5 participants	1 participants

SECONDARY outcome

Timeframe: Outpatients were followed for the duration of hospital stay, an average of six hours.

In groups A, B and C was determined the rate of subjective clinical signs of increased Met-Hb-Levels : headaches or dizziness, when correlated with the peak-Met-Hb-Level.

Outcome measures

Outcome measures
Measure	Group A : 40ml Prilocaine 1% n=40 Participants 40 outpatients : 40ml prilocaine 1% were administered for axillary plexus block	Group B : 30ml Prilocaine 1% n=40 Participants 40 outpatients : 30ml prilocaine 1% were administered for axillary plexus block	Group C : 20ml Prilocaine 1% n=40 Participants 40 outpatients : 20ml prilocaine 1% were administered for axillary plexus block
Number of Participants With Subjective Adverse Events as a Measure of Safety and Tolerability.	4 participants	0 participants	0 participants

Adverse Events

Group A : 40ml Prilocaine 1%

Serious events: 0 serious events

Other events: 14 other events

Deaths: 0 deaths

Group B : 30ml Prilocaine 1%

Serious events: 0 serious events

Other events: 5 other events

Deaths: 0 deaths

Group C : 20ml Prilocaine 1%

Serious events: 0 serious events

Other events: 1 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure	Group A : 40ml Prilocaine 1% n=40 participants at risk 40 outpatients : 40ml Prilocaine 1% were administered for axillary plexus block	Group B : 30ml Prilocaine 1% n=40 participants at risk 40 outpatients : 30ml prilocaine 1% were administered for axillary plexus block	Group C : 20ml Prilocaine 1% n=40 participants at risk 40 outpatients : 20ml prilocaine 1% were administered for axillary plexus block
Nervous system disorders dizziness	7.5% 3/40 • Number of events 3	0.00% 0/40	0.00% 0/40
Nervous system disorders headaches	2.5% 1/40 • Number of events 1	0.00% 0/40	0.00% 0/40
Blood and lymphatic system disorders objective signs of methemoglobinemia	32.5% 13/40 • Number of events 19	12.5% 5/40 • Number of events 5	2.5% 1/40 • Number of events 1

Additional Information

Dr.med.Ronald Seidel

Helios-Kliniken Schwerin

Phone: 0049 (0)385 520-4251

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place