Board #303 - Technology Innovation Development and Validation of a Capillary Refill Simulator (Submission #8272)

Abstract

Introduction In a pediatric mass casualty event, emergency personnel are trained to employ a disaster triage system for determining the severity of each child’s injuries and the urgency of care required. However, while various algorithms exist, few have been validated in fully simulated disaster scenarios. This is because some clinical features are difficult to replicate in actor patients, including capillary refill time (CRT). CRT is a simple test of a patient’s hemodynamic stability and is thus a critical decision point in many algorithms, but it has proven challenging to simulate. Our objective was to design a portable, realistic model that was able to simulate normal and abnormal CRT, followed by a two-phase study to evaluate its realism and feasibility in both a tabletop drill and a disaster simulation drill. Its direct comparison was a video of matching CRT portrayed on actual fingers, displayed on an iPod or on a computer screen. Description A portable CRT simulator was developed using LED technology that ’blanched’ when pressure was applied and returned to a baseline pink over time. A simulation facilitator could set the speed of color return anywhere from two to ten seconds long using a wired dial control. The current prototype was powered by a simple nine volt battery and could be placed on top of a volunteer’s chest or a manikin. First, emergency medicine physicians (n=27) interacted with the CRT modalities and determined whether the CRT was normal or prolonged. They also assessed the devices’ appearance and utility using a ten cm visual analog scale (VAS). A total of ten capillary refill tabletop scenarios were conducted. In the next phase, medical students trained to utilize a disaster triage system (n=33) and participated in a multi-casualty disaster drill. They used the CRT simulators in their assessment of four live mock-patients and a video depicting CRTs in seven computer-based scenarios. Variables assessed were their ratings of realism using the same VAS tool. Data analyses were done using a related samples Wilcoxon Rank Sum Test between the CRT simulator compared to the video recorded equivalent. Conclusion Accuracy in determining CRT as normal or prolonged was 93% on the simulator and 71% with the iPod (p < 0.001). For the tabletop exercises, subjects scored iPod appearance at 83mm and simulator appearance at 64mm (p < 0.005). They scored the contextual realism of the iPod at 49mm and of the simulator at 67mm (p <0.001). Those in an actual disaster drill scored video CRT appearance at 71mm and simulator appearance at 86mm (p = 0.086). They scored the contextual realism of the iPod at 60mm and of the simulator at 74mm (p = 0.013). The simulator portrayed more accurate and reliable CRTs than video clips. While the videos scored higher in visual appearance ratings, the simulator was significantly more realistic contextually. Similar results were found in mock-disaster scenarios, with a trend towards higher appearance scores in the iPod videos but significantly higher contextual ratings using the simulator. The findings suggest that an LED-based CRT simulator holds promise as a training tool to portray normal or abnormal. Future refinements will strive to enhance visual appearance instead of contextual realism, and broader applications to disaster drills, septic shock, and other injuries or diseases.