To determine if biofeedback in a simulated patient environment impacts the effectiveness of cardiopulmonary resuscitation (CPR).
Eight subjects (house staff and medical students) performed closed chest compressions on a human patient simulator (HPS, METI, Sarasota FL) at rates of 80, 100 and 120 beats per minute (bpm) synchronized to a metronome. Each set of compressions lasted 2.5 minutes with the generated systolic blood pressure (SBP) and cardiac output (CO) recorded with the HPS software. In addition, the blood pressure tracing was visible to the person performing CPR. Linear regression quantified the association between CO and SBP at each cadence, with CO as the dependent variable and SBP - cadence interaction as independent variables. Standard errors were adjusted for within-subject clustering.
SBP and CO are highly correlated at all compression rates, accounting for 96% of CO variance at 80 bpm (R2=0.96, p < 0.0001); 97% of CO variance at 100 bpm (R2=0.96, p < 0.0001); and 83% of CO variance at 120 bpm (R2=0.83, p = 0.002). Compared to 80- and 100-bpm, the association between SBP and CO is significantly lower at 120 bpm (β=−0.008, p = 0.049).
The HPS allows the learner to discern the importance of rate, force and depth of chest compressions during CPR via instantaneous visual feedback utilizing the blood pressure tracing. The model suggests a compression rate of 120 bpm may reduce CO while rates of 80 or 100 bpm are equally effective at generating SBP and CO. Biofeedback provides valuable information allowing for accurate task completion.
Improving the effectiveness of CPR training through utilization of HPS with instantaneous biofeedback shows promise as a training tool. Instantaneous biofeedback with blood pressure generated during CPR is possible with HPS.
Patrick Mailloux, No Financial Disclosure Information; No Product/Research Disclosure Information