Table 1.
Baseline characteristics of the study population.
| All patients (n = 590) | Train set (n = 283) | Validation set (n = 70) | Test set (n = 237) | |
|---|---|---|---|---|
| Age, years | 71 [58–82] | 68 [58–81] | 72 [63–82] | 73 [58–82] |
| Sex, male | 349 (59.2) | 167 (59.0) | 41 (58.6) | 141 (59.5) |
| Cause of CPA | ||||
| Internal causes | ||||
| Cardiac | 306 (51.9) | 147 (51.9) | 40 (57.1) | 119 (50.2) |
| Respiratory | 54 (9.2) | 26 (9.2) | 3 (4.3) | 25 (10.5) |
| Neurological | 45 (7.6) | 20 (7.1) | 7 (10.0) | 18 (7.6) |
| Other internal causes | 28 (4.7) | 13 (4.6) | 5 (7.1) | 10 (4.2) |
| External causes | ||||
| Asphyxia | 106 (18.0) | 49 (17.3) | 12 (17.1) | 45 (19.0) |
| Hanging | 27 (4.6) | 18 (6.4) | 1 (1.4) | 8 (3.4) |
| Drowning | 5 (0.8) | 2 (0.7) | 1 (1.4) | 2 (0.8) |
| Trauma | 5 (0.8) | 2 (0.7) | 0 (0) | 3 (1.3) |
| Other external causes | 14 (2.4) | 6 (2.1) | 1 (1.4) | 7 (3.0) |
| Witnessed cardiac arrest | 397 (67.3) | 181 (64.0) | 49 (70.0) | 167 (70.5) |
| Bystander CPR | 293 (49.7) | 138 (48.8) | 35 (50.0) | 120 (50.6) |
| Initial electrical rhythm | ||||
| Asystole | 227 (38.5) | 111 (39.2) | 26 (37.1) | 90 (38.0) |
| PEA | 186 (31.5) | 86 (30.4) | 22 (31.4) | 78 (32.9) |
| VF/Pulseless VT | 177 (30.0) | 86 (30.4) | 22 (31.4) | 69 (29.1) |
| Interval from call to EMS arrival, minutes | 7 [6–8] | 7 [6–8] | 7 [6–8] | 7 [5–8] |
| Interval from call to hospital arrival, minutes | 35 [29–41] | 35 [29–41] | 35 [29–40] | 35 [29–41] |
| Prehospital ROSC | 328 (55.6) | 154 (54.4) | 42 (60.0) | 132 (55.7) |
| Extracorporeal-CPR | 103 (17.5) | 51 (18.0) | 10 (14.3) | 42 (17.7) |
| Therapeutic hypothermia | 139 (23.6) | 63 (22.3) | 17 (24.3) | 59 (22.4) |
| Outcome | ||||
| Survival at discharge | 326 (55.3) | 159 (59.0) | 38 (54.3) | 129 (54.4) |
| Good neurological outcome (CPC 1 or 2) at discharge | 97 (16.4) | 44 (15.5) | 14 (20.0) | 39 (16.5) |
All data are presented as median [interquartile range] or N (%). CPA, cardiopulmonary arrest; CPR, cardiopulmonary resuscitation; PEA, pulseless electrical activity; VF, ventricular fibrillation; VT, ventricular tachycardia; EMS, emergency medical service; ROSC, return of spontaneous circulation; CPC, cerebral performance category.