Evaluation of Possible Tourniquet Systems for Use in the Canadian Forces

Abstract

Hemorrhage from extremity wounds is the leading cause of preventable death on the battlefield. Tourniquets have been identified as the most reasonable option for controlling life threatening extremity hemorrhage in the tactical phase of an operation. The purpose of this trial was to determine which tourniquet systems are effective under simulated combat conditions and make recommendations to the Canadian Forces (CF) on an approach to tourniquet use. 5 tourniquet systems were tested: Self Applied Tourniquet System (SATS); One-Handed Tourniquet (OHT); tie & cravat Improvised Tourniquet (IT); pneumatic Emergency Medical Tourniquet (EMT); and latex surgical tubing (ST). On June 25, 2004, ten junior medics from 1 Field Ambulance volunteered for the study. They were divided into five groups of two and rotated through all tourniquets. Each group was timed on the speed of application, and effectiveness of the tourniquets on the lower limbs was determined by a Doppler probe and loss of palpable pulses. Subjective analysis by questionnaire was used to determine ease of use, durability, portability, patient comfort, and preference. Occlusion of the posterior tibial pulse, as measured by Doppler flow, occurred 0-10% of the time with the OHT, 40-50% with the SATS and IT, 70-80% with the EMT, and 90% with the ST. The presence of winter clothing did not change the effectiveness of the tourniquets. The OHT, SATS, IT, and EMT took an average of 30-40 seconds to apply while the ST took only 24 seconds. From most painful to least were: the IT (severe pain-could not tolerate); ST and SATS (moderate-severe pain); OHT (minor-moderate pain); and EMT (no pain-minor discomfort). The most effective tourniquets were the EMT and ST. The ST is also the lightest, fastest, easiest to learn, and the cheapest but it causes a lot of pain and presumably, local tissue damage. ST can be issued to every soldier with a minimum of training and used effectively in the "Care Under Fire" phase. The EMT, which causes the least pain and is equally effective, can be applied during the "Tactical Field Care" phase by the medic to replace the surgical tubing. Fine adjustments can be made to the EMT, which allows the medic to safely deflate the device, assess the wound, determine if a tourniquet is required, and re-inflate quickly if necessary.