Unadjusted and adjusted analyses of variables associated with return of spontaneous circulation (ROSC)
| Variable | No. (%) of patients* | OR (95% CI) | ||
|---|---|---|---|---|
| ROSC n = 2216 | No ROSC n = 5626 | Unadjusted | Adjusted† | |
| Age, yr, mean ± SD | 71.0 ± 15.4 | 70.6 ± 16.0 | 1.00 (0.99–1.00) | 1.00 (1.00–1.01) |
| Sex, male | 1325/2216 (59.8) | 3525/5626 (62.7) | 0.89 (0.80–0.98) | 0.74 (0.67–0.83) |
| Event witnessed by bystander | 1310/2194 (59.7) | 1921/5592 (34.4) | 2.83 (2.56–3.14) | 2.47 (2.22–2.75) |
| Contact at or above floor 3 | 478/2216 (21.6) | 1366/5626 (24.3) | 0.86 (0.76–0.96) | 0.90 (0.79–1.02) |
| Bystander performed CPR | 889/2216 (40.1) | 1884/5626 (33.5) | 1.33 (1.20–1.47) | 1.16 (1.04–1.29) |
| 911 response time, min, mean ± SD | 6.1 ± 2.3 | 6.2 ± 2.3 | 0.99 (0.97–1.01) | 0.98 (0.95–1.00) |
| Initial shockable rhythm present | 668/2212 (30.2) | 711/5591 (12.7) | 2.97 (2.63–3.35) | 2.39 (2.10–2.72) |
| Time from arrival of 911 responder to patient contact, min, mean ± SD | 3.3 ± 2.3 | 3.5 ± 2.3 | 0.97 (0.95–0.99) | NA |
Note: CI = confidence interval, CPR = cardiopulmonary resuscitation, NA = not applicable, OR = odds ratio, SD = standard deviation.
↵* Except where indicated otherwise.
↵† Adjusted for age, sex, witness status, bystander CPR, 911 response time, initial cardiac rhythm and floor of contact (< 3 v. ≥ 3).