Table 2.
Adjusted odds ratios for 24-hour survival and good neurological outcome from binary logistic regression analysis
| 24-hour survival | Good neurological outcome | |||
|---|---|---|---|---|
| OR (95% CI) | P value | OR (95% CI) | P value | |
| Patients without PCI (n = 430) | ||||
| Hypothermia | 8.24 (4.24 to 16.0) | <0.001 | 2.13 (1.17 to 3.90) | 0.014 |
| Fibrinolysis | 0.52 (0.28 to 0.98) | 0.042 | 0.59 (0.25 to 1.38) | 0.223 |
| Location at home | 1.42 (0.92 to 2.20) | 0.116 | 1.59 (0.86 to 2.92) | 0.137 |
| Age <60 years | 1.45 (0.89 to 2.36) | 0.135 | 2.25 (1.24 to 4.07) | 0.007 |
| Witnessed OHCA | 1.04 (0.64 to 1.68) | 0.889 | 1.33 (0.66 to 2.69) | 0.423 |
| Bystander CPR | 3.52 (1.84 to 6.76) | <0.001 | 1.45 (0.67 to 3.16) | 0.35 |
| VF/pVT as first ECG rhythm | 1.96 (1.21 to 3.16) | 0.006 | 2.27 (1.26 to 4.09) | 0.006 |
| Cardiac etiology | 0.80 (0.47 to 1.34) | 0.391 | 0.72 (0.36 to 1.50) | 0.358 |
| Patients with normothermia (n = 405) | ||||
| PCI | 4.46 (2.26 to 8.80) | <0.001 | 10.81 (5.86 to 19.93) | <0.001 |
| Fibrinolysis | 0.32 (0.16 to 0.63) | <0.001 | 0.40 (0.15 to 1.05) | 0.064 |
| Location at home | 1.39 (0.90 to 2.17) | 0.141 | 1.44 (0.79 to 2.63) | 0.237 |
| Age <60 years | 1.59 (0.98 to 2.58) | 0.063 | 2.04 (1.10 to 3.78) | 0.024 |
| Witnessed OHCA | 1.19 (0.73 to 1.93) | 0.496 | 1.97 (0.92 to 4.21) | 0.08 |
| Bystander CPR | 2.50 (1.34 to 4.69) | 0.004 | 0.99 (0.44 to 2.24) | 0.976 |
| VF/pVT as first ECG rhythm | 2.15 (1.33 to 3.48) | 0.002 | 1.47 (0.79 to 2.73) | 0.23 |
| Cardiac etiology | 1.06 (0.62 to 1.83) | 0.821 | 1.37 (0.61 to 3.09) | 0.445 |
| All patients (n = 584) | ||||
| Hypothermia | 7.50 (4.12 to 13.65) | <0.001 | 1.27 (0.79 to 2.03) | 0.327 |
| PCI | 3.88 (2.11 to 7.13) | <0.001 | 5.66 (3.54 to 9.03) | <0.001 |
| Fibrinolysis | 0.39 (0.22 to 0.71) | <0.001 | 0.63 (9.33 to 1.22) | 0.171 |
| Location at home | 1.29 (0.86 to 1.93) | 0.223 | 1.03 (0.66 to 1.63) | 0.888 |
| Age <60 years | 1.79 (1.14 to 2.82) | 0.012 | 2.87 (1.83 to 4.49) | <0.001 |
| Witnessed OHCA | 1.31 (0.84 to 2.06) | 0.237 | 1.83 (1.02 to 3.27) | 0.042 |
| Bystander CPR | 2.27 (1.26 to 4.08) | 0.006 | 0.72 (0.39 to 1.32) | 0.287 |
| VF/pVT as first ECG rhythm | 1.81 (1.17 to 2.80) | 0.008 | 1.61 (1.01 to 2.54) | 0.043 |
| Cardiac etiology | 1.0 (0.61 to 1.64) | 0.997 | 1.33 (0.70 to 2.50) | 0.385 |
In contrast to Tables S1 to S6 in Additional file 1, which show detailed backward elimination starting with all candidate variables (step 1) and deleting any that were not significant (up to step 6), this table summarizes the adjusted odds ratio (OR) with 95% confidence interval (95% CI) from the respective step before deleting in the next step. Backwards stepwise binary logistic regression analysis was performed for 24-hour survival and good neurological outcome taking into account the following confounding factors: age, location of out-of-hospital cardiac arrest (OHCA), presumed etiology, bystander cardiopulmonary resuscitation (CPR), witnessing, first electrocardiogram (ECG) rhythm (ventricular fibrillation (VF)/pulseless ventricular tachycardia (pVT)), and systemic fibrinolysis. We performed three approaches for subgroup analysis by evaluating: hypothermia as an independent predictor in patients without any coronary intervention (n = 430), percutaneous coronary intervention (PCI) as an independent predictor in patients without hypothermia (n = 405), and the impact of both hypothermia and PCI in all patients (n = 584).