Preliminary Comparison of Pneumatic Models of Tourniquet for Prehospital Control of Limb Bleeding in a Manikin Model.

BACKGROUND: Emergency tourniquet use has been associated with hemorrhage control and improved survival during the wars since 2001, but little is known of the differential performance of pneumatic tourniquet models. The purpose of this study was to compare the performance of three models of pneumatic tourniquets in a laboratory setting to aid a possible decision to field test suitable models for medic preference. METHODS: A laboratory experiment was designed to test the effectiveness of tourniquets on a manikin thigh. Three models (one Emergency and Military Tourniquet [EMT] and two Tactical Pneumatic Tourniquets differing in width: 2 in. and 3 in. [TPT3]) were compared with the standard-issue Combat Application Tourniquet of a strap-and-windlass design. Two users conducted 40 tests each on a right-thigh manikin (HapMed Leg Tourniquet Trainer) with a simulated above-knee amputation injury. Measurements included effectiveness in hemorrhage control, pulse stoppage distal to the tourniquet, time to stop bleeding, blood loss, and pressure. RESULTS: All four models were 100% effective in both hemorrhage control and pulse stoppage distal to the tourniquet. The TPT3 had the slowest mean time to stop bleeding and the highest mean blood loss. The EMT had the least mean pressure. An interuser difference was found only for mean pressure. CONCLUSIONS: All models of tourniquet performed equally well for both the critical outcome of effectiveness and the important outcome of pulse stoppage, whereas results for secondary outcomes (time, pressure, and blood loss) differed by model. The EMT had best performance for every type of measurement.

Preliminary Comparison of New and Established Tactical Tourniquets in a Manikin Hemorrhage Model.

BACKGROUND: Emergency tourniquet use has been associated with hemorrhage control and improved survival during the wars since 2001. The purpose of the present study is to compare the differential performance of two new tactical tourniquets with the standard-issue tourniquet to provide preliminary evidence to guide decisions on device development. METHODS: A laboratory experiment was designed to test the effectiveness of tourniquets on a manikin thigh. Three models of tourniquets were assessed. The Rapid Application Tourniquet System (RATS) and the Tactical Mechanical Tourniquet (TMT) were compared with the standard-issue Combat Application Tourniquet(®) (C-A-T). Two users conducted 30 tests each. RESULTS: Percentages for effectiveness (hemorrhage control, yes/no) and distal pulse cessation did not differ significantly by model. When compared with the RATS, the C-A-T performed better (ρ < .001) for time to hemorrhage control and fluid loss. The C-A-T and TMT had comparable responses for most measures, but the C-A-T applied more pressure (ρ = .04) than did the TMT for hemorrhage control. CONCLUSION: All three tactical tourniquets showed substantial capacity for hemorrhage control. However, the two new tourniquet models (RATS and TMT) did not offer any improvement over the C-A-T, which is currently issued to military services. Indeed, one of the new models, the RATS, was inferior to the C-A-T in terms of speed of application and simulated loss of blood. Opportunities were detected for refinements in design of the two new tourniquets that may offer future improvements in their performance.