Evaluating Tourniquet Application in Law Enforcement Officers During Simulated Hemorrhagic Shock

Objectives: Tourniquet (TQ) application is a critical self-care skill for law enforcement. Current training paradigms predominantly occur under controlled, simulated conditions. However, the impact of acute physiological stressors on the ability to self-apply a TQ remains poorly understood. This pilot study employed a lower-body negative pressure model to simulate hemorrhagic shock and investigate the effects on TQ self-application efficacy. Methods: Twelve (n = 12) law enforcement officers with prior formal training in TQ self-application participated in this study. After donning tactical body armor, each participant entered a lower-body negative pressure (LBNP) tube and was tested under two conditions: an experimental (EXP) condition, where 80–100 mmHg of negative pressure was applied to induce central hypotension and simulated hypovolemia, and a control (CON) condition with no LBNP. Participants were instructed to self-apply a Combat Application Tourniquet to their non-dominant upper extremity in each condition. Successful application was confirmed via manual palpation, Doppler ultrasonography, and visual inspection. The absence of radial artery flow was the primary success criterion. Results: All 12 participants completed the study protocol. Mean age and BMI were 39 years (SD 6) and 28.7 kg/m² (SD 4.9), respectively. Mean systolic blood pressure in the EXP condition was 101 mmHg (SD 19.8) at the beginning of TQ application. Application of TQ was successful in 10 of 12 participants in CON and 8 of 12 participants in the EXP condition, but times did not differ (p = 0.3). Failures in both conditions were attributed to insufficient TQ tightening despite anatomically correct placement. One participant experienced syncope in the EXP condition before completing the TQ application, and another reported pre-syncopal symptoms. Conclusions: These preliminary findings suggest that simulated hemorrhagic shock impairs TQ self-application performance. These results highlight the need for further investigation into the interplay between physiological stress and procedural efficacy. Future work should inform training protocols and policy development aimed at enhancing survivability through optimized self-care in austere operational settings.