Table 1 Baseline characteristics of the ETCO2 group and the untreated group
Variables | ETCO2 group | Untreated group | P value | ||
|---|---|---|---|---|---|
(n = 83) | (n = 4958) | ||||
Male, no. (%) | 44 | 53.0 | 3138 | 63.3 | 0.054 |
Mean age in years (SD) | 71.3 | 15.2 | 67.9 | 17.6 | 0.088 |
Attempted defibrillation, no. (%) | 14 | 16.9 | 878 | 17.7 | 0.842 |
Mean CPR time (10 min) (SD) | 2.4 | 1.4 | 2.4 | 1.6 | 0.927 |
Socioeconomic status, no. (%) | 0.236 | ||||
Low | 56 | 67.5 | 3586 | 72.3 | |
Moderate | 26 | 31.3 | 1212 | 24.5 | |
High | 1 | 1.2 | 160 | 3.2 | |
Urbanization level, no. (%) | 0.118 | ||||
Urban | 26 | 31.3 | 1174 | 23.7 | |
Suburban | 29 | 35.0 | 2259 | 45.6 | |
Rural | 28 | 33.7 | 1525 | 30.7 | |
Diabetes, no. (%) | 25 | 30.1 | 1255 | 25.3 | 0.318 |
Hypertension, no. (%) | 43 | 51.8 | 2434 | 49.1 | 0.624 |
Coronary artery disease, no. (%) | 16 | 19.3 | 1075 | 21.7 | 0.598 |
Hyperlipidemia, no. (%) | 21 | 25.3 | 893 | 18.0 | 0.087 |
Malignancies, no. (%) | 6 | 7.2 | 231 | 4.7 | 0.273 |
Heart failure, no. (%) | 1 | 1.2 | 255 | 5.1 | 0.105 |
Atrial fibrillation, no. (%) | 3 | 3.6 | 107 | 2.2 | 0.368 |
Charlson comorbidity index score, no. (%) | 0.821 | ||||
0 | 25 | 30.1 | 1631 | 32.9 | |
1 | 24 | 28.9 | 1307 | 26.4 | |
≥ 2 | 34 | 41.0 | 2020 | 40.7 | |
Intracerebral hemorrhage, no. (%) | 1 | 1.2 | 108 | 2.2 | 0.545 |
Ischemic stoke, no. (%) | 16 | 19.3 | 887 | 17.9 | 0.744 |
Chronic renal insufficiency, no. (%) | 2 | 2.4 | 233 | 4.7 | 0.326 |
Liver cirrhosis, no. (%) | 16 | 19.3 | 550 | 11.1 | 0.019 |
Health care institutes, no. (%) | <0.001 | ||||
Medical centers | 36 | 43.4 | 1108 | 22.3 | |
Regional hospitals | 41 | 49.4 | 2497 | 50.4 | |
Local hospitals | 6 | 7.2 | 1333 | 26.9 | |
Clinics | 0 | 0 | 20 | 0.4 | |
Mean propensity score (SD) | 0.046 | 0.041 | 0.016 | 0.021 | <0.001 |