Related Experiment Video
Updated: Jul 18, 2026

In Vivo Electrophysiological Measurement of the Rat Ulnar Nerve with Axonal Excitability Testing
Published on: February 6, 2018
Time-dependent changes in median nerve sensory amplitude after local anesthetic administration and tourniquet
Wendy L Timpson1, Xuan Kong, Ward P Hamlet
1NeuroMetrix, Inc., Waltham, Massachusetts 02451, USA.
Abstract:
Indirect visualization, as used in several newer mini-open and endoscopic carpal tunnel release (CTR) procedures, may increase the possibility of nerve injury in some cases. Intraoperative neural monitoring may be used to evaluate nerve location and integrity. In the study reported here, we assessed the feasibility of intraoperative neural monitoring by systematically exploring the effect of local anesthetic and tourniquet on median sensory amplitude. Results for 30 median nerves (7 symptomatic) showed that sensory amplitude decreased, on average, 54% with lidocaine injection, 15% with tourniquet application, and 47% with the combination. Sensory amplitudes of 9 of 10 nerves were still above 1.0 microV 15 minutes after anesthetic administration and tourniquet application. Study results demonstrate that intraoperative monitoring, using the amplitude of the median sensory nerve response, is viable under CTR conditions.
More Related Videos
Related Concept Videos
Local Anesthetics: Differential Sensitivity of Nerve Fibers
Local Anesthetics: Clinical Application as Intravenous Regional Anesthesia
One of the advantages of...
Local Anesthetics: Adverse Effects
Once absorbed into the systemic circulation, local anesthetics can affect the organs that depend on the functioning of sodium...
Local Anesthetics: Pharmacokinetics
Local Anesthetics: Clinical Application as Spinal Anesthesia

