Table 2. Baseline Characteristics of Sample.
| Characteristic | Patients by shock etiology, No. (%) | P value | ||||
|---|---|---|---|---|---|---|
| All (N = 12 695) | Cardiogenic shock (n = 3615) | Septic shock (n = 3998) | Hypovolemic shock (n = 1457) | Other causes of shock (n = 3625) | ||
| Age, mean (SD), y | 65.7 (19.1) | 68.3 (16.1) | 69.8 (17.7) | 65.3 (19.6) | 58.6 (21.2) | <.001 |
| Male | 6411 (50.5) | 2160 (59.8) | 1940 (48.5) | 682 (46.8) | 1629 (44.9) | <.001 |
| Female | 6284 (49.5) | 1455 (40.2) | 2058 (51.5) | 775 (53.2) | 1996 (55.1) | <.001 |
| Accessibility and Remoteness Index of Australia | ||||||
| Major cities of Australia | 9147 (73.3) | 2600 (73.2) | 2887 (72.6) | 1085 (75.2) | 2575 (73.4) | .60 |
| Inner regional Australia | 2706 (21.7) | 783 (22.0) | 883 (22.2) | 288 (20.0) | 752 (21.4) | |
| Outer regional Australia | 629 (5.0) | 171 (4.8) | 206 (5.2) | 70 (4.9) | 182 (5.2) | |
| Index of Relative Socioeconomic Disadvantage | ||||||
| 1, most disadvantaged | 3063 (27.2) | 865 (26.8) | 997 (27.9) | 354 (27.6) | 847 (26.8) | .48 |
| 2 | 2449 (21.8) | 690 (21.9) | 784 (21.9) | 301 (23.5) | 674 (21.3) | |
| 3 | 2187 (19.4) | 633 (19.6) | 704 (19.7) | 238 (18.6) | 612 (19.3) | |
| 4 | 1975 (17.6) | 561 (17.4) | 625 (17.5) | 207 (16.2) | 582 (18.4) | |
| 5, least disadvantaged | 1577 (14.0) | 481 (14.9) | 464 (13.0) | 181 (14.1) | 451 (14.2) | |
| Preexisting medical conditions | ||||||
| Hypertension | 3927 (33.2) | 1348 (41.5) | 1246 (32.0) | 433 (31.4) | 900 (27.1) | <.001 |
| Dyslipidemia | 2301 (19.4) | 841 (25.9) | 705 (18.1) | 248 (18.0) | 507 (15.3) | <.001 |
| Diabetes | 2165 (18.3) | 709 (21.8) | 737 (18.9) | 303 (22.0) | 416 (12.5) | <.001 |
| Coronary artery disease | 2154 (18.2) | 835 (25.7) | 667 (17.1) | 222 (16.1) | 430 (12.9) | <.001 |
| Cardiac failure | 1286 (10.9) | 439 (13.5) | 490 (12.6) | 115 (8.4) | 242 (7.3) | <.001 |
| Chronic kidney disease | 731 (6.2) | 223 (6.9) | 272 (7.0) | 95 (6.9) | 141 (4.2) | <.001 |
| Peripheral vascular disease | 187 (1.6) | 52 (1.6) | 76 (2.0) | 24 (1.7) | 35 (1.1) | .02 |
| Cerebrovascular disease | 908 (7.7) | 240 (7.4) | 345 (8.9) | 99 (7.2) | 224 (6.7) | <.001 |
| Airways disease | 1209 (10.2) | 320 (9.9) | 577 (14.8) | 97 (7.0) | 215 (6.5) | <.001 |
| Initial systolic blood pressure, median (IQR), mm Hga | 70 (0-80) | 58 (0-80) | 75 (60-80) | 70 (55-80) | 70 (0-80) | <.001 |
| Initial heart rate, median (IQR), beats/min | 90 (70-120) | 84 (50-124) | 100 (80-120) | 90 (74-112) | 86 (68-110) | <.001 |
| Initial temperature, mean (SD), °C | 36.2 (1.6) | 35.8 (1.4) | 36.8 (1.7) | 35.9 (1.7) | 36.1 (1.6) | <.001 |
| Initial oxygen saturation, mean (SD) % | 90.4 (12.7) | 89.2 (16.7) | 89.2 (10.9) | 93.5 (8.5) | 91.9 (10.6) | <.001 |
| Initial respirator rate, median (IQR), breaths/min | 18 (16-24) | 16 (0-20) | 22 (18-32) | 18 (16-24) | 16 (16-20) | <.001 |
| Intensive care paramedic attendance | 5960 (46.9) | 2460 (68.0) | 1529 (39.8) | 496 (34.0) | 1457 (40.2) | <.001 |
| Time at scene, median (IQR), min | 30 (20-46) | 41 (25-60) | 27 (20-39) | 26 (18-36) | 27 (17-42) | <.001 |
| Transport time, median (IQR), min | 18 (11-28) | 18 (11.7-27) | 19 (12-29) | 18 (11-29) | 18 (11-28) | .11 |
| Prehospital intubation | 1878 (14.8) | 1385 (38.3) | 100 (2.5) | 20 (1.4) | 373 (10.3) | <.001 |
| Prehospital cardiac arrest requiring CPRb | 1906 (15) | 1518 (42) | 67 (1.7) | 20 (1.4) | 301 (8.3) | <.001 |
| Epinephrine infusion commenced | 3845 (30.3) | 1960 (54.2) | 903 (22.5) | 113 (7.8) | 869 (24) | <.001 |
| Maximum epinephrine infusion, mean (SD), µg/min | 30.1 (48.7) | 40.9 (57.0) | 12.6 (18.7) | 18.5 (35.8) | 23.5 (41.0) | <.001 |
| Epinephrine infusion, mean (SD) µg/min | 21.8 (33.9) | 29.3 (39.9) | 9.6 (12.4) | 14.1 (25.2) | 18.7 (30.9) | <.001 |
Abbreviation: CPR, cardiopulmonary resuscitation.
a
Undetectable initial blood pressure was recorded as 0 mm Hg.
b
Determined from Victorian Ambulance Cardiac Arrest registry.