Short Report Comparing Generation 6 Versus Prototype Generation 7 Combat Application Tourniquet(r) in a Manikin Hemorrhage Model

BACKGROUND: The Combat Application Tourniquet® (C-A-T) is the standard-issue military tourniquet used in first aid in 2015, and the current model is called Generation 6. Soldiers in the field, however, have been asking for design changes in a possible Generation 7 to improve ease of use. This study compared the differential performance in use of the C-A-T in two designs: Generation 6 (C-A-T 6) versus a prototype Generation 7 (C-A-T 7). METHODS: A laboratory experiment was designed to test the performance of two tourniquet designs in hemorrhage control, ease of use, and user preference. Ten users of the two C-A-T models placed them on a manikin thigh to stop simulated bleeding. Users included trauma researchers and instructors of US Army student medics. Ten users conducted 20 tests (10 each of both designs). RESULTS: Most results were not statistically significant in their difference by C-A-T design. The mean difference in blood loss was statistically significant (ρ = .03) in that the C-A-T 7 performed better than the C-A-T 6, but only in the mixed statistical model analysis of variance, which accounted for user effects. The difference in ease-of-use score was statistically significant (ρ = .002); the C-A-T 7 was easier. All users preferred the C-A-T 7. CONCLUSION: In each measure, the C-A-T Generation 7 prototype performed similar or better than Generation 6, was easier to use, and was preferred.