Utstein style analysis of rural out-of-hospital cardiac arrest [OOHCA]: Total cardiopulmonary resuscitation (CPR) time inversely correlates with hospital discharge rate

Objective: Survival after out-of-hospital cardiac arrest (OOHCA) in an urban environment is directly proportional to speed of defibrillation and effective bystander cardiopulmonary resuscitation (CPR). We hypothesized that the hospital discharge rate from rural OOHCA was affected by the same factors. Methods: We studied all OOHCAs in 1998 for rural Alachua County, Florida, with one emergency medical system (EMS) transport provider and three hospitals. All EMS identified OOHCA were reviewed retrospectively, as were EMS and hospital records. The 1998 County population was 211 403; 1495 deaths from all causes occurred (70.7/10⁴ pop). Of 167 OOHCAs (7.9/10⁴ pop), 145 were of cardiac etiology; 22 were excluded (13 scene deaths, four traumatic, one intraoperative and three respiratory arrests, one arrest during a hospital-to-hospital transfer) and in eight outcome data were not available in any form. A total of 137/145 (94.5%) OOHCA patients had analyzable data. Data were analyzed using Student's t-test and ANOVA. Alpha was set at 0.05. Results: Of 25 patients (18.2% of OOHCA) with restoration of spontaneous circulation (ROSC), six survived (4.4% of total, 24% of those with ROSC) to discharge from hospital (four to a skilled nursing facility, one each home with and without assistance). Four patients were still alive at ≥1 year post arrest. Asystole as the initial rhythm (P=0.014), and emergency department (ED) CPR time (8 vs. 15.5 min, P=0.042 for survivors vs. non-survivors) were the only factors statistically affecting survival. While bystander CPR was not significantly different between groups, there was a significantly higher proportion of patients surviving in the ED who had ROSC, and a higher proportion who had ROSC after bystander CPR. Time to defibrillation in nonsurvivors, while not statistically different between city and county patient groups, was clinically different. Statistical significance would likely have been achieved with a larger study population. Conclusion: Our data suggest improvement in response time and bystander CPR might further improve survival in a rural setting.