Abstract 56: The Effects of Obesity on CPR Quality and Survival after Cardiac Arrest
Background The prevalence of obesity has risen drastically over the past two decades yet cardiopulmonary resuscitation (CPR) remains a “one size fits all” therapy. The recent AHA resuscitation guidelines have placed increased emphasis on CPR quality, and especially decreasing time without compressions, although the guidelines do not specify tailoring CPR for individual patient characteristics such as body habitus.
Objectives To determine whether outcomes from cardiac arrest are affected by body mass index (BMI) and whether obesity affects CPR quality.
Methods A prospective, observational study of adult in-hospital cardiac resuscitations was conducted between December 2002 and December 2005. An investigational monitor/defibrillator equipped to measure compression characteristics during CPR was used. All patients for whom body mass index (BMI) data was available were included in this analysis.
Results Data were analyzed from 76 patients. Of those, 41 (54%) were average in size (BMI < 30 kg/m2), 25 (33%) were obese (BMI ≥30, <40) and 10 (13%) were morbidly obese (BMI ≥40). There was no difference in rates of return of spontaneous circulation (ROSC) between average and obese patients but morbidly obese patients trended toward worse outcomes than patients with lower BMIs (20% vs 39% ROSC; p=0.24). The fraction of cardiac arrest time during which no compressions were being administered was significantly higher in average-sized patients compared with patients whose BMI was ≥30 (27% vs 17%; p=0.005). However, morbidly obese patients trended towards receiving shallower chest compressions than smaller patients (42 mm vs 45 mm, p=0.44).
Conclusions Morbid obesity may be associated with worse outcomes from cardiac arrest, yet in our cohort these patients received less time without chest compressions. This suggests that other CPR characteristics, such as chest compression depth, may be important determinants of survival.