Virtual Reality Simulation for Assessment of Hemorrhage Control and SALT Triage Performance: A Comparison of Prehospital to In-Hospital Emergency Responders

Abstract

Introduction: Targeted identification, effective triage, and rapid hemorrhage control are essential for optimal outcomes of mass-casualty incidents (MCIs). An important aspect of Emergency Medical Service (EMS) care is field triage, but this skill is difficult to teach, assess, and research.

Study objective: This study assessed triage efficacy and hemorrhage control of emergency responders from different professions who used the Sort, Assess, Life-Saving Treatment (SALT) triage algorithm in a virtual reality (VR) simulation of a terrorist subway bombing.

Methods: After a brief just-in-time training session on the SALT triage algorithm, participants applied this learning in First VResponder, a high-fidelity VR simulator (Tactical Triage Technologies, LLC; Powell, Ohio USA). Participants encountered eleven virtual patients in a virtual scene of a subway station that had experienced an explosion. Patients represented individuals with injuries of varying severity. Metrics assessed included triage accuracy and treatment efficiency, including time to control life-threatening hemorrhage. Independent Mann-Whitney analyses were used to compare two professional groups on key performance variables.

Results: The study assessed 282 participants from the ranks of EMS clinicians and medical trainees. Most (94%) participants correctly executed both global SALT sort commands. Participants triaged and treated the entire scene in a mean time of 7.8 decimal minutes, (95%CI, 7.6-8.1; SD = 1.9 decimal minutes) with a patient triage accuracy rate of 75.8% (95%CI, 74.0-77.6; SD = 15.0%). Approximately three-quarters (77%) of participants successfully controlled all life-threatening hemorrhage, within a mean time of 5.3 decimal minutes (95%CI, 5.1-5.5; SD = 1.7 decimal minutes). Mean time to hemorrhage control per patient was 0.349 decimal minutes (SD = 0.349 decimal minutes). Overall, EMS clinicians were more accurate with triage (P ≤ .001) and were faster at triage, total hemorrhage control (P < .01), and hemorrhage control per patient (P < .004) than medical trainees.

Conclusions: Through assessments using VR simulation, it was observed that more experienced individuals from the paramedic (PM) workforce out-performed less experienced medical trainees. The study also observed that the medical trainees performed acceptably, even though their only formal training in SALT triage was a 30-minute, just-in-time lecture. Both of these findings are important for establishing evidence that VR can serve as a valid platform for assessing the complex skills of triage and treatment of an MCI, including the assessment of rapid hemorrhage control.

Keywords: Emergency Medical Services; disaster planning; educational; emergency responders; hemorrhage control; mass-casualty incidents; triage; virtual reality.

Figure 1.

The First VResponder Simulation Experience. Note: Participants don a virtual reality (VR) head-mounted display (HMD) and encounter patients within a subway bombing scenario (right). Participants use their voice and hand-held controllers to interact with a VR system to diagnose and treat patients (upper left). Participants have a medical supply bag available allowing them to choose different interventions for treating patients (lower left).

Figure 2.

SALT Adherence Performance for All Responders. Note: The x-axis indicates the number of patients that were treated out of order (errors). Fewer patients treated out of order indicates better performance. The orange bars indicate the percentage of responders that performed at that level. The blue bars indicate the percentage of responders that performed at that level or below (cumulative).

Figure 3.

(a) Triage Accuracy by Group; (b) Triage Errors by Category and Group - Trial Errors Categorized as Over-Triage, Under-Triage, and Critical Errors; (c) Triage Accuracy by Tag. Abbreviations: PM, paramedic; EMT; emergency medical technician; RES, emergency medicine resident; MS, medical student.

Figure 4.

Time to Triage the Scene (left), Time to Hemorrhage Control (middle), and Time to Hemorrhage Control per Patient (right) by Group. Note: The line within the boxplot indicates the median and the black square indicates the mean. Abbreviations: PM, paramedic; EMT; emergency medical technician; RES, emergency medicine resident; MS, medical student.