Table 1.
Patient and event details for 9,667 patients with out-of-hospital cardiac arrest.
| Total (n = 9667) | 0001–0600 (n = 1428) | 0601–1200 (n = 2887) | 1201–1800 (n = 2877) | 1801–2400 (n = 2475) | p-value* | |
|---|---|---|---|---|---|---|
| Age, median (IQR) | 68 (24) | 65 (26) | 69 (24) | 70 (23) | 68 (24) | 0.70 |
| Male, n (%) | 6448 (66.7) | 959 (67.1) | 1935 (67.0) | 1946 (67.6) | 1609 (65.0) | 0.21 |
| Initial Rhythm | <0.001 | |||||
| VF/VT, n (%) | 2682 (27.7) | 346 (24.2) | 764 (26.5) | 861 (29.9) | 711 (28.7) | |
| PEA, n (%) | 1892 (19.6) | 282 (19.7) | 539 (18.7) | 552 (19.2) | 519 (21.0) | |
| Asystole, n (%) | 3601 (37.3) | 592 (41.4) | 1135 (39.3) | 1004 (34.9) | 871 (35.2) | |
| AED no-shock, n (%) | 1002 (10.4) | 148 (10.5) | 303 (10.5) | 285 (9.9) | 265 (10.7) | |
| Unknown, n (%) | 490 (5.1) | 60 (4.2) | 146 (5.1) | 175 (6.1) | 110 (4.4) | |
| Location of Arrest | <0.001 | |||||
| Public, n (%) | 1752 (18.1) | 94 (6.6) | 512 (17.7) | 741 (25.8) | 406 (16.4) | |
| Private, n (%) | 7910 (81.8) | 1335 (93.4) | 2376 (82.3) | 2132 (74.1) | 2067 (83.5) | |
| Unknown, n (%) | 5 (0.0) | 0 | 0 | 4 (0.1) | 1 (0.0) | |
| Witness Status | <0.001 | |||||
| Witnessed, n (%) | 5213 (53.9) | 814 (57.0) | 1406 (48.7) | 1627 (56.6) | 1365 (55.2) | |
| Unwitnessed, n (%) | 4454 (46.1) | 614 (43.0) | 1481 (51.3) | 1250 (43.4) | 1109 (55.8) | |
| Bystander Resuscitation | <0.001 | |||||
| CPR Attempted, n (%) | 2801 (29.0) | 384 (26.9) | 773 (26.8) | 927 (32.2) | 718 (29.0) | |
| AED Shock, n (%) | 151 (1.6) | 4 (0.3) | 37 (1.3) | 85 (3.0) | 25 (1.0) | |
| AED Applied no shock, n (%) | 69 (0.1) | 10 (0.7) | 20 (0.7) | 21 (0.7) | 18 (0.7) | |
| Median (IQR) EMS Time Intervals in minutes | ||||||
| Total out of hospital | 38 (17) | 41 (18) | 38 (18) | 37 (17) | 39 (16.4) | 0.46 |
| Response | 6 (3) | 6 (3) | 5 (3) | 5 (3) | 6 (3) | 0.87 |
| On Scene | 24 (14) | 27 (14.5) | 24 (14) | 23 (14) | 24 (14) | 0.61 |
| Transport | 6 (6) | 7 (5.4) | 6 (6) | 6 (6) | 6 (6) | 0.99 |
| Time to CPR | 8 (4) | 10 (5) | 8 (5) | 8 (5) | 8 (4) | 0.75 |
| Time to Shock† | 11 (11) | 13 (11.9) | 11 (11) | 11 (10) | 11 (11) | 0.56 |
Abbreviations: VF/VT = ventricular fibrillation or ventricular tachycardia, PEA = pulseless electrical activity, AED no shock = automated external defibrillator no shock advised, CPR=cardiopulmonary resuscitation, EMS = Emergency medical services, AED shock = automated external defibrillator shock advised, IQR = interquartile range, Total out of hospital = time interval from call received at dispatch to prehospital death or emergency department arrival. Response = time interval from time call received at dispatch to first vehicle at scene. On Scene = time interval from first vehicle arrival on scene to prehospital death or transport from scene. Transport = time interval from transport from scene to emergency department arrival. Time to CPR = time interval from call received at dispatch to onset of EMS cardiopulmonary resuscitation. Time to shock = time from call received at dispatch to the first EMS defibrillation attempt for those with a rhythm of VF/VT.
Time intervals were compared across time blocks with an ANOVA model with a covariance matrix that accounts for multiple imputation. All other variables were compared across time blocks with a Chi-squared goodness-of-fit test.
Among those with ventricular fibrillation or pulseless ventricular tachycardia.