Sequence times of field resuscitation and outcome sorted by bystander intervention of AED and BCPR timing
| AED <3 min (n=22) | AED ≥3 min (n=10) | No AED shock (n=10) | ||||
| BCPR≤1 min (n=22) | 1 min＜BCPR ≤3 min (n=0) | BCPR≤1 min (n=7) | 1 min＜BCPR ≤3 min (n=3) | BCPR≤1 min (n=7) | 1 min＜BCPR ≤3 min (n=3) | |
| First responder factors | ||||||
| Interval between collapse to start of BCPR, median (IQR), min | 0.5 (0.5) | NA | 1.0 (0.5) | 2.0 (2.0) | 0.5 (0.5) | 3 (2.25) |
| First Responder who performed initial chest compressions, n (%) | ||||||
| Paramedics/paramedic students | 13 | NA | 2 | 1 | 3 | 2 |
| Running physicians/physicians at first aid station | 7 | NA | 2 | 2 | 2 | 1 |
| Volunteers | 1 | NA | 3 | NA | 2 | NA |
| Runners (including healthcare provider who participated in a race) | 1 | NA | NA | NA | NA | NA |
| Initial ECG waveform by AED analysis, n (%) | ||||||
| VF | 22 (100%) | NA | 7 (100%) | 3 (100%) | 1 | NA |
| PEA | NA | NA | NA | NA | 6 | 2 |
| Asystole | NA | NA | NA | NA | NA | 1 |
| Interval between collapse to AED shock delivery, median (IQR), min | 1.5 (1.0) | NA | 5.0 (4.0) | 5.0 (4.5) | NA | NA |
| Interval between collapse to first narrow QRS appearance, median (IQR), sec | 116 (94) | NA | 346 (320) | 267 (267) | 64 (69) | 168 (155) |
| EMS factors | ||||||
| Interval between collapse and ROSC, median (IQR), min | 4.0 (3.0) | NA | 7.0 (6.5) | 7.0 (5.0) | 2 (1.25) | 6.5 (6.25) |
| Interval between collapse and EMS arrival, median (IQR), min | 10.5 (9.0) | NA | 19.0 (15.5) | 16.0 (16.0) | 13 (9.5) | 13 (12.5) |
| Initial ECG waveform analysed by EMS, n (%) | ||||||
| Sinus rhythm | 20 (90.9%) | NA | 7 (100%) | 3 (100%) | 6 (85.7%) | 2 |
| VF | 1 (4.5%) | NA | NA | NA | ||
| Asystole / PEA | 1 (4.5%) | NA | NA | NA | 1 (14.3%) | 1 |
| Outcome variables | ||||||
| Field ROSC, n (%) | 20 (90.9%) | NA | 7 (100%) | 3 (100%) | 6 (85.7%) | 2 (66.7%) |
| CPC1-2 at 1 month, n (%) | 21 (95.5%) | NA | 7 (100%) | 3 (100%) | 6 (85.7%) | 2 (66.7%) |
| CPC1-2 at 1 year, n (%) | 21 (95.5%) | NA | 7 (100%) | 3 (100%) | 6 (85.7%) | 2 (66.7%) |
BCPR ≤1 min: BCPR was initiated within 1 min.
1 min <BCPR≤3 min: BCPR was initiated between 1 min and 3 min.
AED <3min: AED was delivered within 3 min.
AED ≥3 min: AED was delivered after 3 min.
AED, automated external defibrillator; CPC, cerebral performance category; CPR, cardiopulmonary resuscitation; ECG, electrocardiogram; EMS, emergency medical service; EMT, emergency medical technician; NA, not applicable; PEA, pulseless electrical activity; ROSC, return of spontaneous circulation; VF, ventricular fibrillation.