Laboratory Evaluation of the First Generation Everyday Carry Tourniquet and Everyday Carry Tourniquet-Wide Emergency Extremity Tourniquets in Healthy Human Volunteers

Background and Aim : Several existing commercial, off-the-shelf (COTS) tourniquet devices are available on the market and in common use. Early data comparing COTS tourniquet designs available at the time for selection by the US Army Institute for Surgical Research (USAISR) for military use was obtained during a laboratory trial in 2005. We sought to evaluate the Gen 1 Everyday Carry Tourniquet (ETQ) and Everyday Carry Tourniquet – Wide (ETQ-W) (Snakestaff Systems) using a similar methodology to the 2005 USAISR study. Methods Experiment I evaluated the ETQ and ETQ-Wide on the mid-thigh. The starting leg, right vs left, was alternated with each participant, and the unit tested first was double-alternated to control for possible confounders. Participants (n = 20) were instructed on how to apply and tension the tourniquets while evaluators used Doppler ultrasound at the popliteal artery. Participants tightened the tourniquets until the popliteal pulse was obliterated or the participant refused to tighten further due to pain. Participants then rated and characterized the pain. Experiment II was performed similarly with tourniquet placement mid-humerus and Doppler ultrasound pulse monitoring at the radial artery (n = 20). Results For Experiment I, both the ETQ and ETQ-Wide successfully occluded the pulse, as determined by loss of Doppler ultrasound signal, in 95% of participants. The mean pain scores were 3.3 (ETQ) and 3.5 (ETQ-W), with pinching pain reported in a minority of tests. For Experiment II, both the ETQ and ETQ-Wide successfully occluded the pulse, as determined by loss of Doppler ultrasound signal, in 100% of participants. The mean pain score was 5.6 (ETQ) and 5.7 (ETQ-W), with pinching pain reported in a minority. No mechanical or structural failures of either the ETQ or ETQ-W were observed. Conclusions Our research suggests that the ETQ and ETQ-Wide are efficacious tourniquet devices for controlling life-threatening extremity hemorrhage.