J. C. McCarty1,2, J. P. Herrera-Escobar1, Z. G. Hashmi1, E. De Jager1, M. A. Chaudhary1, A. H. Haider1, C. J. Ezeibe1, E. J. Caterson2, E. Goralnick1,3 1Brigham And Women’s Hospital,Center For Surgery And Public Health, Department Of Surgery, Harvard Medical School,Boston, MA, USA 2Brigham And Women’s Hospital,Division Of Plastic Surgery,Boston, MA, USA 3Brigham And Women’s Hospital,Department Of Emergency Medicine,Boston, MA, USA
Introduction: Multiple national initiatives advocate for laypeople to be trained in hemorrhage control to decrease preventable deaths in trauma. The American College of Surgeons Bleeding Control Basic (B-Con) course is the most common hemorrhage control training in the world and teaches participants how to use a Combat Application Tourniquet (CAT). There are, however, multiple types of commercial tourniquets available and programs across the country have placed different tourniquet types in publicly available bleeding control kits. We compared laypeople’s ability to apply different commercial tourniquets and to improvise a tourniquet immediately after taking the B-Con course.
Methods: Participants were assessed immediately after completing the B-Con course on their ability to apply different tourniquets to a Hapmed trainer— a high-fidelity mannequin that simulates bleeding, which decreases as the tourniquet tightens, and records the pressure applied by the tourniquet and the estimated blood loss (EBL). Every participant applied all 5 tourniquet types in a randomized sequence: CAT, Sof-Tourniquet (Sof-T), Stretch-Wrap-And-Tuck (SWAT) tourniquet, Rapid Application Tourniquet (RAT), and an improvised tourniquet (available gauze, shoestring, stick/windlass, and belt). The primary outcome was correct tourniquet application defined as pressure >250mmHg and time < 2minutes. Secondary outcomes were pressure applied by the tourniquet and EBL if applied correctly. Paired univariate tests were used to compare each tourniquet type to the CAT as an internal control for all outcomes.
Results: 61 laypeople were evaluated. Participants correctly applied the CAT tourniquet at a significantly higher rate than all other tourniquet types (p<0.001)(Figure). For the improvised tourniquet, 11 people did not use a windlass and their success rate was 0%. The CAT applied more pressure than all other tourniquet types (mean±SD: 403.5±103.1 mmHg, p<0.001 for each comparison), followed by the Sof-T (326.8±162.2 mmHg), improvised tourniquet (180.8±169.5mmHg), SWAT (126.0±131.9 mmHg), and RAT (107.0±120.3mmHg). Among tourniquets applied correctly, the CAT had the lowest EBL (209.0±76.5 ml, p<0.001 for each comparison) followed by the Sof-T (248.4±108.1 ml), RAT (315.1±108.3 ml), SWAT (339.9±187.1 ml) and improvised tourniquet (477.0±174.0 ml).
Conclusion: B-Con is most effective at teaching participants only the single tourniquet type taught in the course. As new tourniquets come to market, this study raises concern that those trained today will not know how to use new devices; they know a single skill rather than the underlying principle. This study highlights a significant limitation of current guidelines and training in an area ripe for improvement and innovation. (Clinicaltrials.gov NCT03538379)
