A comparison of efficacy, efficiency, and durability in novel tourniquet designs.

BACKGROUND: Exsanguination due to extremity hemorrhage is a major cause of preventable traumatic deaths. Extremity tourniquet use has been shown to be safe and improve survival. The purpose of this study was to compare the efficacy, efficiency, and durability of the Generation 7 Combat Application Tourniquet (CAT; North American Rescue, Greer, SC), the Tactical Mechanical Tourniquet (TMT; Combat Medical Systems, Harrisburg, NC), and the SOF Tactical Tourniquet-Wide (SOFTT-W; Tactical Medical Solutions, Anderson, SC). METHODS: This study was a three-phase randomized, cross-over trial. In successive trials, subjects were timed during the application of each tourniquet to the upper and lower extremity. Following successful lower extremity application, subjects low crawled 25 ft and then were dragged 25 ft, after which effectiveness was reassessed, as defined by the cessation of distal pulses by Doppler ultrasound. RESULTS: In arm application, both the CAT and TMT had significantly less failure rates than the SOFTT-W (5.56%, 19.44%, 58.33%), with the CAT being the fastest tourniquet when compared with TMT and SOFTT-W (37.8 seconds, 65.01 seconds, 63.07 seconds). In leg application, the CAT had significantly less rates of failure when compared with the SOFTT-W, but there was no other significant difference between the tourniquets (27.78%, 44.44%, 61.11%). In addition, the CAT was significantly faster than both the TMT and SOFTT-W when applied to the leg (8.33 seconds, 40.96 seconds, 34.5 seconds). There was no significant difference in tourniquet failure rates between the three tourniquets after subject maneuvers in phase 3 (34.29%, 42.86%, 45.45%). DISCUSSION: The CAT is as effective as the TMT and significantly more effective than the SOFTT-W. In addition, the CAT demonstrated shorter application times than either the TMT or SOFTT-W. However, there was no significant difference between the three tourniquets in their ability to maintain pulselessness after subject maneuvers. LEVEL OF EVIDENCE: Care management, level II.