Table 1. Baseline characteristics of cohort.
| All N = 3523 |
18-63 years N = 1199 (34%) |
64-77 years N = 1164 (33%) |
> 77 years N = 1160 (33%) |
P-value | |
| Data are presented as mean ± SD or n (%). *Determined by Victorian Ambulance Cardiac Arrest Registry (VACAR) linkage; † shock aetiology determined by hospital primary ICD discharge diagnosis derived through linkage with VEMD and VAED datasets; ‡ arrhythmia included hospital primary discharge diagnoses of complete heart block, atrial tachyarrhythmias, and ventricular arrhythmias. COPD: chronic obstructive airways disease; ICD: international classification of diseases; NSTEMI: non-ST elevation myocardial infarction; STEMI: ST elevation myocardial infarction; SVT: supraventricular tachycardia. | |||||
| Mean age | 68.4 ± 16 | 50.1 ± 10.6 | 70.9 ± 4 | 84.9 ± 4.9 | < 0.001 |
| Female | 1,398 (40%) | 435 (36%) | 409 (35%) | 554 (48%) | < 0.001 |
| Hypertension | 1309 (41%) | 262 (26%) | 517 (48%) | 530 (48%) | < 0.001 |
| Dyslipidemia | 826 (26%) | 160 (16%) | 344 (32%) | 322 (29%) | < 0.001 |
| Diabetes mellitus | 702 (22%) | 186 (19%) | 274 (25%) | 242 (22%) | 0.001 |
| Pre-existing coronary artery disease | 827 (26%) | 154 (16%) | 311 (29%) | 362 (33%) | < 0.001 |
| Pre-existing heart failure | 435 (14%) | 51 (5.1%) | 144 (13%) | 240 (22%) | < 0.001 |
| Chronic kidney disease | 222 (7%) | 58 (5.8%) | 64 (5.9%) | 100 (9.1%) | 0.004 |
| Peripheral vascular disease | 52 (1.6%) | 6 (0.6%) | 23 (2.1%) | 23 (2.1%) | 0.008 |
| Cerebral vascular disease | 234 (7.4%) | 40 (4%) | 79 (7.3%) | 115 (10%) | < 0.001 |
| COPD | 319 (10%) | 57 (5.7%) | 159 (15%) | 103 (9.3%) | < 0.001 |
| Pre-hospital cardiac arrest* | 905 (26%) | 365 (30%) | 314 (27%) | 226 (20%) | < 0.001 |
| Shock aetiology† | |||||
| STEMI | 505 (14%) | 198 (17%) | 173 (15%) | 134 (12%) | 0.002 |
| NSTEMI | 190 (5.4%) | 30 (2.5%) | 71 (6.1%) | 89 (7.7%) | < 0.001 |
| Decompensated heart failure | 257 (7.3%) | 66 (5.5%) | 69 (14.9%) | 122 (11%) | < 0.001 |
| Cardiac arrest | 1463 (42%) | 639 (53%) | 528 (45%) | 296 (26%) | < 0.001 |
| Arrhythmias‡ | 947 (27%) | 334 (28%) | 313 (27%) | 300 (26%) | < 0.001 |
| Mean initial systolic blood pressure, mmHg | 85.5 ± 29.6 | 86.2 ± 29.1 | 87.9 ± 32.7 | 83.2 ± 27.3 | 0.011 |
| Mean initial heart rate, beats/min | 97.7 ± 27.9 | 110.8 ± 51.5 | 96.6 ± 45.6 | 86.9 ± 43.6 | < 0.001 |
| Pre-hospital intubation | 1307 (37%) | 558 (47%) | 484 (42%) | 265 (23%) | < 0.001 |
| Pre-hospital epinephrine infusion commenced | 1880 (53%) | 678 (57%) | 694 (60%) | 508 (44%) | < 0.001 |