Tourniquet Pain (Coombs, PI)

Control of Tourniquet Pain with an Axillary Ring of Local Anesthetic

Tourniquets used to limit bleeding during upper extremity surgery can cause significant discomfort to patients having surgery under regional anesthesia. There are multiple reasons for “tourniquet pain”, but one contributing factor is thought to be pressure on the soft inner aspect of the upper arm. The two nerves covering this area can be blocked with a subcutaneous injection of local anesthetic. It is common practice to block these two nerves, but it has never been proven that this procedure, by itself, significantly reduces tourniquet pain. In this study, we will inject volunteers with local anesthetic or normal saline and assess their degree of tourniquet discomfort over a 1 hour period. Each subject will return for a second session during which he or she will receive the opposite injection to the one that was given during the first session. Researchers will be blinded as to which type of injection is given first or second. Analysis of the subjects’ subjective pain scores and the time they are able to tolerate tourniquet inflation will allow us to see if “numbing” the inner aspect of the upper arm significantly reduces tourniquet pain.