Table 2.
Case mix of out of hospital cardiopulmonary arrests by aetiology
| Presumed cardiac disease (n=17 451) | Non-cardiac internal aetiologies (n=1814) | External aetiologies (n=1910) | Total (n=21 175) | ||
| Sex | Male | 12 190 (70) | 1052 (58) | 1377 (72) | 14 619 (69) |
| Female | 5234 (30) | 757 (42) | 526 (28) | 6517 (31) | |
| Missing data | 27 | 5 | 7 | 39 | |
| Age | Median (IQR) | 67 (59 to 75) | 67 (57 to 75) | 35 (25 to 55) | 66 (56 to 74) |
| Missing data | 0 | 0 | 0 | 0 | |
| Carstairs socioeconomic deprivation category | 1–2 | 2298 (15) | 207 (13) | 208 (14) | 2713 (15) |
| 3–5 | 10 034 (65) | 1050 (66) | 927 (61) | 12 011 (65) | |
| 6–7 | 3000 (20) | 333 (21) | 377 (25) | 3710 (20) | |
| Missing data | 2119 | 224 | 398 | 2741 | |
| Arrest site | Home | 10 329 (59) | 1389 (77) | 885 (46) | 12 603 (60) |
| Other | 7117 (41) | 420 (23) | 1020 (54) | 8557 (40) | |
| Missing data | 5 | 5 | 5 | 15 | |
| Witness | Crew | 1669 (11) | 263 (16) | 168 (11) | 2100 (11) |
| Bystander | 10 291 (67) | 958 (60) | 580 (40) | 11 829 (64) | |
| No-one | 3365 (22) | 380 (24) | 716 (49) | 4461 (24) | |
| Missing data | 2126 | 213 | 446 | 2785 | |
| Bystander CPR* | Yes | 6147 (40) | 444 (29) | 645 (38) | 7236 (39) |
| No | 9337 (60) | 1072 (71) | 1073 (62) | 11 482 (61) | |
| Missing data | 298 | 35 | 24 | 357 | |
| Call–response interval* | ≤4 min | 3245 (19) | 294 (16) | 284 (15) | 3823 (18) |
| >4 min | 14 067 (81) | 1506 (84) | 1614 (85) | 17 187 (82) | |
| Missing data | 139 | 14 | 12 | ||
| Defibrillated | Yes | 10 308 (59) | 515 (28) | 376 (20) | 11 199 (53) |
| No | 7126 (41) | 1294 (72) | 1532 (80) | 9952 (47) | |
| Missing data | 17 | 5 | 2 | 24 | |
| Number of shocks† | 1 | 2904 (28) | 192 (38) | 152 (42) | 3248 (29) |
| ≥2 | 7293 (72) | 314 (62) | 210 (58) | 7817 (71) | |
| Missing data | 111 | 9 | 14 | 134 |
Values are n (%).
*Non-crew witnessed arrests only.
†Defibrillated patients only.
CPR, cardiopulmonary resuscitation; IQR, interquartile range.