Background: Common first aid tourniquets, like the Combat Application Tourniquet (CAT) of a windlass and band design, can have the band routed through the buckle in three different ways, and recent evidence indicates users may be confused with complex doctrine.
Objective: The purpose of the present study is to measure the differential performance of the three possible routings in order to better understand good tourniquet practice.
Methods: A training manikin was used by two investigators to measure tourniquet effectiveness, time to stop bleeding, and blood loss.
Results: The effectiveness rate was 99.6% (239/240) overall. RESULTS were similar for both single-slit routings (inside vs. outside, p > 0.05). Effectiveness rates (yes-no results for hemorrhage control expressed as a proportion of iterations) were not statistically different between single and double routing. However, the time to stop bleeding and blood loss were statistically different (p < 0.05).
Conclusions: CAT band routing, through the buckle either singly or doubly, affects two key performance criteria: time to stop bleeding and volume of blood lost. Single routing proved to be faster, thereby saving more blood. Learning curves required to optimize user performance varied over 30-fold depending on which variable was selected (e.g., effectiveness vs. blood loss).