BYSTANDER VS EMS FIRST-RESPONDER CPR - INITIAL RHYTHM AND OUTCOME IN WITNESSED NONMONITORED OUT-OF-HOSPITAL CARDIAC-ARREST

Objectives: To assess whether outcome and first-monitored rhythm for p atients who sustain a witnessed, nonmonitored, out-of-hospital cardiac arrest are associated with on-scene CPR provider group. Methods: A re trospective, cohort analysis was conducted in a suburban, heterogeneou s EMS system. Patients studied were greater than or equal to 19 years of age, had had an arrest of presumed cardiac origin between July 1989 and January 1993, had gone into cardiac arrest prior to ALS arrival, and had received CPR on collapse. First-monitored rhythms and survival rates were compared for two patient groups who on collapse either: 1) had received CPR by nonprofessional bystanders (BCPR) or 2) had recei ved CPR by on-scene EMS system first responders (FRCPR). Results: Of 2 17 cardiac arrest victims, 153 (71%) had received BCPR and 64 (29%) ha d received FRCPR. The BCPR patients were slightly younger (62.4 vs 68. 4 years, p = 0.01) and had slightly shorter ALS response intervals (6. 4 vs 7.7 minutes, p = 0.02). There was no difference in BLS response t ime intervals or automatic external defibrillator (AED) use rates. The percentage of patients with a first-monitored rhythm of pulseless ven tricular tachycardia/ventricular fibrillation (VT/VF) and the percenta ge of patients grouped by CPR provider who survived to hospital admiss ion or to hospital discharge were: GRAPHICS Controlling for age, the odds ratio for VT/VF with BCPR was 5.45 (95% CI 2.8, 10.3). Conclusio n: Patients who receive BCPR more often have a first-monitored rhythm of VT/VF than do FRCPR patients, despite both CPR-provider groups' ini tiating CPR essentially immediately after patient collapse. Hence, BCP R and FRCPR groups have different first-monitored arrest rhythms, whic h may affect survival rate. These patient populations should not be co nsidered to be homogeneous groups in CPR research.