Table 1 Patient characteristics of the entire cohort and matched cohort
| Â | Entire cohort | Matched cohort | ||||
|---|---|---|---|---|---|---|
No ECPR | ECPR | SMD | No ECPR | ECPR | SMD | |
N = 117,907 | N = 484 |  | N = 1832 | N = 458 |  | |
Demographics | ||||||
Age, mean (SD) [years] | 70.1 (15.0) | 55.2 (14.2) | 1.022 | 56.4 (16.1) | 55.5 (14.1) | 0.059 |
Female sex | 43,296 (36.7) | 88 (18.2) | 0.425 | 358 (19.5) | 84 (18.3) | 0.031 |
Urbanisation level of residence | Â | Â | 0.586 | Â | Â | 0.067 |
 Metropolitan | 70,077 (59.4) | 407 (84.1) |  | 1538 (84.0) | 382 (83.4) |  |
 Urban | 34,241 (29.0) | 65 (13.4) |  | 229 (12.5) | 64 (14.0) |  |
 Rural | 13,589 (11.5) | 12 (2.5) |  | 65 (3.5) | 12 (2.6) |  |
Year of arrest | Â | Â | 0.277 | Â | Â | 0.107 |
 2013–2014 | 23,093 (19.6) | 90 (18.6) |  | 292 (15.9) | 87 (19.0) |  |
 2015–2016 | 27,763 (23.5) | 72 (14.9) |  | 266 (14.5) | 71 (15.5) |  |
 2017–2018 | 31,104 (26.4) | 139 (28.7) |  | 575 (31.4) | 132 (28.8) |  |
 2019–2020 | 35,947 (30.5) | 183 (37.8) |  | 699 (38.2) | 168 (36.7) |  |
Past medical history | ||||||
 Diabetes | 28,154 (23.9) | 112 (23.1) | 0.017 | 405 (22.1) | 108 (23.6) | 0.035 |
 Hypertension | 41,693 (35.4) | 178 (36.8) | 0.029 | 708 (38.6) | 170 (37.1) | 0.032 |
 Heart disease | 20,402 (17.3) | 95 (19.6) | 0.060 | 328 (17.9) | 90 (19.7) | 0.045 |
 Stroke | 10,789 (9.2) | 18 (3.7) | 0.223 | 69 (3.8) | 18 (3.9) | 0.009 |
Circumstance of arrest | ||||||
 Day of arrest, weekend | 34,500 (29.3) | 103 (21.3) | 0.184 | 342 (18.7) | 100 (21.8) | 0.079 |
 Time of arrest, night | 76,565 (64.9) | 277 (57.2) | 0.159 | 1035 (56.5) | 262 (57.2) | 0.014 |
Witness status | Â | Â | 0.499 | Â | Â | 0.065 |
 No | 58,537 (49.6) | 128 (26.4) |  | 525 (28.7) | 122 (26.6) |  |
 Layperson | 47,409 (40.2) | 269 (55.6) |  | 1011 (55.2) | 252 (55.0) |  |
 EMS | 11,961 (10.1) | 87 (18.0) |  | 296 (16.2) | 84 (18.3) |  |
Place of arrest, public | 20,118 (17.1) | 193 (39.9) | 0.523 | 686 (37.4) | 180 (39.3) | 0.038 |
Bystander characteristics | ||||||
 Bystander CPR | 64,455 (54.7) | 268 (55.4) | 0.014 | 1025 (55.9) | 248 (54.1) | 0.036 |
 Bystander defibrillation | 581 (0.5) | 8 (1.7) | 0.113 | 29 (1.6) | 8 (1.7) | 0.013 |
EMS characteristics | ||||||
 Multi-tier response | 58,158 (49.3) | 254 (52.5) | 0.063 | 1029 (56.2) | 235 (51.3) | 0.098 |
 Response time | 7.0 [5.0, 9.0] | 6.0 [5.0, 9.0] | 0.173 | 6.0 [5.0, 8.0] | 6.0 [5.0, 9.0] | 0.046 |
 Scene time | 13.0 [9.0, 17.0] | 13.0 [9.0, 18.0] | 0.011 | 13.0 [9.0, 18.0] | 13.0 [9.0, 18.0] | 0.064 |
 Transport time | 6.0 [4.0, 10.0] | 7.0 [5.0, 9.0] | 0.064 | 6.0 [4.0, 9.0] | 7.0 [5.0, 9.0] | 0.007 |
Initial cardiac rhythm | Â | Â | 1.248 | Â | Â | 0.037 |
 Shockable | 16,057 (13.6) | 292 (60.3) |  | 1052 (57.4) | 271 (59.2) |  |
 PEA | 23,270 (19.7) | 100 (20.7) |  | 394 (21.5) | 96 (21.0) |  |
 Asystole | 78,580 (66.6) | 92 (19.0) |  | 386 (21.1) | 91 (19.9) |  |
EMS managements | ||||||
 IV-line insertion | 46,917 (39.8) | 254 (52.5) | 0.257 | 1047 (57.2) | 238 (52.0) | 0.104 |
 Mechanical CPR device use | 15,018 (12.7) | 79 (16.3) | 0.102 | 324 (17.7) | 72 (15.7) | 0.053 |
 Advanced airway management | 73,537 (62.4) | 337 (69.6) | 0.154 | 1341 (73.2) | 316 (69.0) | 0.093 |
 EMS defibrillation | 24,199 (20.5) | 328 (67.8) | 1.082 | 1204 (65.7) | 304 (66.4) | 0.014 |
Any ROSC prior to ED arrival | 4603 (3.9) | 57 (11.8) | 0.296 | 237 (12.9) | 52 (11.4) | 0.048 |