Abstract P58: Rescuer Height and Use of a Step-Stool During Cardiopulmonary Resuscitation Correlate with Increased Chest Compression Depth and Incomplete Chest Recoil
INTRODUCTION: Shallow chest compressions and incomplete recoil are common during cardiopulmonary resuscitation (CPR) and negatively affect outcomes. However, the optimal rescuer positioning to maximize compression depth and minimize incomplete recoil is not known.
METHODS: We conducted a simulated study of in-hospital cardiac arrest using a CPR mannequin placed on a standard hospital bed, set at a height of 63 cm. Rescuers performed a total of four 2-min segments of uninterrupted chest compressions, followed by 2 min breaks, alternating use, or not, of a 23 cm step-stool. Compression characteristics were measured using a CPR-sensing defibrillator and results were compared using paired and unpaired t-tests, as appropriate. Multivariate linear regression was used to assess the independent contribution of rescuer characteristics.
RESULTS: Fifty Advanced Cardiac Life Support/Basic Life Support certified subjects with a mean age of 33±10 y and median height of 169.8 (range 148.6–190.5) cm volunteered to participate. Thirty six percent were men. When no stool was used, mean compression depth increased with increasing rescuer height quintiles, from 36±8 to 50±16 mm; p=0.03. Addition of a stool increased depth from 46±13 to 50±11 mm; p=0.0003. However, the difference was only significant at the lowest height quintile (<163.8 cm), where depth increased by 11±9 mm; p=0.003. Incomplete recoil also increased with increasing height from 14 to 66% (p=0.004), without a stool. Use of a stool resulted in a height-independent 18% increase in incomplete release; p<0.0001. After adjusting for other rescuer characteristics, including sex, upper body strength and weight, the only factors found to impact depth were rescuer height and use of a stool. Male sex independently correlated with incomplete recoil. Compression rate and fatigue were not impacted by rescuer height or use of a stool.
CONCLUSIONS: Compression depth and incomplete recoil increase with rescuer height and use of a step-stool. Step-stools should be considered for shorter rescuers performing CPR on a bed, even at its lowest height. Taller rescuers should avoid a step-stool and may even consider raising the hospital bed from its lowest position to avoid incomplete recoil.