The Impact of Nerve Cross Section Area on Sensory Block Onset

Not Applicable

Completed

• Conditions: Regional Anesthesia
• Interventions: Procedure: Dominant Arm; Procedure: Non-dominant arm

• Registration Number: NCT03797235
• Lead Sponsor: Jose Aguirre

Brief Summary

The study aims to describe a correlation between the nerve cross section and the sensory or motor block onset time. Therefore, different nerve cross sections with their Motor and sensory onset times are compared in order to find a correlation.

In the case of discovering a correlation, this could be translated into clinical practice, where a more tailored and individualized approach to performing peripheral nerve blocks would be possible, thus lowering the risks of adverse events occurring.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2019-01-05
• Study First Submitted QC: 2019-01-05
• Study First Posted: 2019-01-09
• Study Start: 2019-01-19
• Primary Completion: 2019-06-20
• Study Completion: 2019-06-21
• Status Verified: 2020-05
• Last Update Submitted: 2020-05-22
• Last Update Posted: 2020-05-22

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 15

Inclusion Criteria

• ASA I - II, both sexes
• ≥ 18 years old
• < 65 years old
• Written informed consent as documented by signature

Exclusion Criteria

• Known allergy or hypersensitivity to a study drug or class of drug.
• Severe coagulopathy.
• History of alcohol abuse or the intake of psychotropic drugs.
• Pregnancy.
• Infection at the injection site or a systemic infection.
• Fever of unknown origin.
• Motor or sensory abnormalities in the arm.
• Previous enrollment into the current study

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Dominant Arm	Dominant Arm	Two ultrasound guided nerve blocks (block of the ulnar and median nerve) on the dominant forearm
Non-dominant arm	Non-dominant arm	Two ultrasound guided nerve blocks (block of the ulnar and median nerve) on the non-dominant forearm.

Primary Outcome Measures

Name	Time	Method
Correlation between nerve cross-section and time to complete sensory block of a nerve	Sensory evaluation will be carried out before the block and every 2 minutes after the start of the injection of LA until complete sensory loss to both cold and pinprick. Expected time frame: 10-60 minutes	Correlation between the nerve cross-section in mm2 of both nerves (median and ulnar) measured with an ultrasound system and time in minutes from the moment the investigator starts injecting the local anesthetic (LA) around the respective nerves to complete sensory loss in the innervation area of the blocked nerve, assessed by response to light touch, pinprick and cold sensation. This correlation will be expressed in min/ mm2.

Secondary Outcome Measures

Name	Time	Method
Correlation between nerve cross-section and the duration of sensory nerve block	The evaluation of the duration of block will start one hour after the determined complete sensory loss and will be tested every 10 minutes until complete resolution of the sensory block. Expected time frame: 10-300 minutes	The correlation between the nerve cross-section area in mm2 of both nerves (median and ulnar) measured with an ultrasound system and the duration of the respective sensory block in minutes, as reflected by the return of normal sensation in the innervation area of the respective nerve. This correlation will be expressed in min/ mm2.
Correlation between the nerve cross-section and duration of motor nerve block	The evaluation of the duration of sensory block will start one hour after the determined complete motor loss and will be tested every 10 minutes until complete resolution of the motor block. Expected time frame: 10-300min	The correlation between the nerve cross-section area in mm2 of both nerves (median and ulnar) measured with an ultrasound system and the duration of the respective motor block in minutes, as reflected by the return of normal muscle strength in the innervation area of the respective nerve. This correlation will be expressed in min/ mm2.
Correlation between nerve cross-section and time to complete motor block of a nerve	Motor evaluation will be carried out before the block and every 2 minutes after the start of the injection of LA until complete motor block. Expected time frame: 10-100 minutes	The correlation between the nerve cross-section area in mm2 of both nerves (median and ulnar) measured with an ultrasound system and time in minutes from the start of the LA injection around the nerve median and ulnar nerves to the respective onset of the motor block, assessed with a numerical scale ranging from 0 to 5 (0-no muscle contraction visible, 5-normal muscle strength, maximal force against resistance and gravity). This correlation will be expressed in min/ mm2.

Trial Locations

Locations (1)

Der Balgrist; 🇨🇭 Zürich, Switzerland