Table 2 Characteristics of patients with OHCA of cardiac origin in each group

Institutions, n

29

28

29

Patients, n

250

817

2565

^dMale, n (%)

170 (68.0%) [0]

575 (70.4%) [0]

1852 (72.2%) [0]

0.106

^dAge, year

70.0 (60.0–82.0) [0]

71.0 (60.0–82.0) [0]

69.0 (58.0–79.0) [0]

< 0.001

Cause of OHCA, n (%)

[0]

[0]

[0]

0.035

 Acute coronary syndrome

77 (30.8%)

269 (32.9%)

805 (31.4%)

 Other cardiac^a

75 (30.0%)

226 (27.7%)

620 (24.2%)

 Presumed cardiac

98 (39.2%)

322 (39.4%)

1140 (44.4%)

^dWitness by bystander, n (%)

171 (68.4%) [0]

564 (69.0%) [0]

1754 (68.4%) [0]

0.839

^dCPR initiated by bystander, n (%)

130 (52.0%) [0]

358 (43.8%) [0]

1233 (48.1%) [0]

0.741

^dDefibrillation by bystander, n (%)

5 (2.0%) [0]

48 (5.9%) [0]

160 (6.2%) [0]

0.025

^dPrimary ECG rhythm at the scene, n (%)

[0]

[0]

[0]

0.042

 Ventricular fibrillation

89 (35.6%)

325 (39.8%)

1113 (43.4%)

 Pulseless ventricular tachycardia

1 (0.4%)

10 (1.2%)

16 (0.6%)

 Pulseless electrical activity

71 (28.4%)

223 (27.3%)

701 (27.3%)

 Asystole

89 (35.6%)

259 (31.7%)

735 (28.7%)

 ^dDefibrillation, n (%)

58 (23.2%) [0]

196 (24.0%) [0]

722 (28.1%) [0]

0.010

 ^dUse of airway devices, n (%)

[0]

[0]

[0]

< 0.001

  Bag valve mask

179 (71.6%)

485 (59.4%)

1041 (40.6%)

  Laryngeal mask airway

5 (2.0%)

21 (2.6%)

171 (6.7%)

  Esophageal obturator airway

53 (21.2%)

267 (32.7%)

940 (36.6%)

  Tracheal intubation

13 (5.2%)

44 (5.4%)

413 (16.1%)

^dIntravenous fluid administration, n (%)

78 (31.6%) [3]

329 (40.3%) [0]

1120 (43.7%) [0]

< 0.001

^dTreatments by doctor before arrival at ED, n (%)

23 (9.2%) [0]

91 (11.1%) [0]

566 (22.1%) [0]

< 0.001

^dAdrenaline dosage until arrival at ED (mg)

0.0 (0.0–2.0) [123]

1.0 (0.0–2.0) [290]

1.0 (1.0–3.0) [1183]

< 0.001

 ^dFrom calling EMS to arrival at the scene (min)

9.0 (7.0–11.0) [0]

8.0 (7.0–10.0) [0]

8.0 (6.0–10.0) [1]

< 0.001

 ^dFrom arrival at the scene to arrival at the ED (min)

22.0 (17.0–29.0) [0]

22.0 (17.0–29.0) [3]

24.0 (18.0–31.0) [27]

< 0.001

ECG rhythm on arrival at ED, n (%)

[0]

[0]

[0]

< 0.001

 Ventricular fibrillation

28 (11.2%)

101 (12.4%)

469 (18.3%)

 Pulseless ventricular tachycardia

5 (2.0%)

8 (1.0%)

15 (0.6%)

 Pulseless electrical activity

65 (26.0%)

220 (26.9%)

645 (25.1%)

 Asystole

87 (34.8%)

249 (30.5%)

714 (27.8%)

 Return of spontaneous circulation

65 (26.0%)

239 (29.3%)

722 (28.1%)

Extracorporeal CPR, n (%)

37 (14.8%) [0]

144 (17.6%) [0]

667 (26.0%) [0]

< 0.001

 Time from arrival at ED to start of VA-ECMO (min)

35.5 (26.8–63.0) [214]

40.5 (29.0–65.0) [673]

29.0 (20.0–41.0) [1902]

< 0.001

 ^dSerum Urea nitrogen (mg/dl)

19.1 (14.1–30.8) [83]

19.0 (14.9–27.0) [314]

18.9 (14.0–26.6) [833]

0.131

 ^dSerum Creatinine (mg/dl)

1.15 (0.95–1.60) [84]

1.13 (0.90–1.43) [316]

1.11 (0.90–1.50) [814]

0.616

 ^dSerum total protein (g/dl)

6.2 (5.7–6.8) [90]

6.1 (5.5–6.7) [311]

6.1 (5.4–6.6) [902]

0.009

 ^dSerum albumin (g/dl)

3.4 (3.0–3.8) [93]

3.4 (2.9–3.8) [332]

3.3 (2.8–3.7) [906]

< 0.001

 ^dpH

7.06 (6.92–7.25) [89]

7.10 (6.93–7.25) [261]

7.06 (6.90–7.25) [755]

0.066

 ^dPaCO₂ (mmHg)

52.3 (38.6–77.4) [92]

52.5 (39.5–73.5) [261]

51.80 (37.3–77.5) [753]

0.863

 ^dPaO₂ (mmHg)

144.0 (82.9–288.7) [98]

137.5 (81.4–280.0) [261]

169.0 (82.6–340.0) [754]

0.012

 ^dHCO3 (mEq/l)

16.2 (12.8–19.7) [96]

16.2 (12.1–19.8) [273]

15.4 (11.9–18.8) [756]

0.006

 ^dBase excess (mEq/l)

−13.1 (−17.9–-7.3) [96]

−13.0 (−18.7–-7.0) [277]

−14.4 (−20.2–-8.6) [765]

< 0.001

 ^dLactate (mg/dl)

100.8 (72.0–129.6) [113]

90.8 (59.2–122.1) [306]

95.0 (65.7–128.7) [778]

0.187

 ^dGlucose (mg/dl)

244.0 (172.25–305.25) [100]

260.5 (198.00–330.50) [279]

263.0 (199.0–330.0) [801]

0.230

^dPatient with ROSC prior to arrival at ED, n (%)

65 (26.0%) [0]

239 (29.3%) [0]

722 (28.1%) [0]

0.854

^dPatient with ROSC after arrival at ED, n (%)

64 (25.6%) [0]

246 (30.1%) [0]

757 (29.5%) [0]

0.439

Time from calling EMS to the first ROSC before arriving at the ED (min)^b

22.0 (15.0-27.0) [177]

18.0 (13.0–25.0) [541]

19.0 (13.0–26.0) [1628]

0.749

Time from calling EMS to the first ROSC after arriving at the ED (min)^c

44.0 (34.0–56.5) [80]

42.5 (34.0–57.0) [335]

44.0 (34.0–57.0) [1072]

0.852

Time from ED arrival to ROSC after admission (min)^c

13.0 (8.0–20.0) [82]

13.0 (8.0–22.0) [335]

13.0 (8.0–24.0) [1074]

0.150

^dMotor score of GCS in ED

1.0 (1.0-1.0) [0]

1.0 (1.0-1.0) [0]

1.0 (1.0-1.0) [0]

0.351

Therapeutic hypothermia, n (%)

74 (29.6%) [0]

256 (31.3%) [0]

955 (37.2%) [0]

< 0.001

Outcomes 30 days after cardiac arrest

[0]

[0]

[0]

 Survive, n (%)

81 (32.4%)

269 (32.9%)

883 (34.4%)

0.353

 Favorable neurological outcome, n (%)

46 (18.4%)

167 (20.4%)

543 (21.2%)

0.308