Key principles of high-performance CPR (HPCPR) include optimizing rate and depth of chest compressions, and minimizing pauses. Maryland EMS sought compromise to translate existing adult HPCPR protocol to accommodate AHA 15:2 compression: ventilation ratio pediatric recommendations. The resulting “Maryland Hiccup” method of HPCPR delivers 1 ventilation on each upstrokes after compressions 14 and 15, resulting in nearly continuous compressions. We sought to determine how the Maryland Hiccup (MH) style of CPR compares to the standard AHA 15:2 (AHA) style in simulated pediatric CPR performed by EMS clinicians. Methods: Teams of 2-person EMS providers utilized a child -size medium fidelity manikin to perform four-minute cycles of HPCPR. Teams were randomly assigned 2 cycles in either MH or AHA style, then crossed over to the other style. HPCPR performance metrics were compared: compression fraction, no flow time, rate, depth, and ventilation rate and volume using student’s t-test. Results: Thirty-eight clinicians (22 BLS, 16 ALS) participated. Both compression fraction (80% with AHA vs 98% with MH, p < .001) and no flow time (2.79 seconds with AHA vs 0.16 seconds with MH, p<.001) were improved with MH technique. Overall compressions were deeper than the recommended 2 inches or 5 cm, with AHA than MH (63mm vs 60mm respectively, p=0.01, Table 1). No differences were noted in compression rate, ventilation rate or ventilation volume. Conclusions: The Maryland Hiccup style of HPCPR with synchronized ventilations interspersed with chest compressions significantly improves CPR quality metrics in simulated pediatric CPR by EMS clinicians. While the CCF was superior with the MH method (98%), the chest compression depth was shallower than the AHA method by 3mm. How this translates to changes in actual patient outcomes has yet to be determined. Further study is warranted to explore physiologic benefits and patient outcome.
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