Table 2.
Cox proportional hazards regression model with ICU mortality as outcome
| Factors | Hazard ratio (95% CI) | p value |
|---|---|---|
| Univariate analysis | ||
| Age | 1.011 (0.998–1.025) | 0.108 |
| Pulmonary contusion | 0.417 (0.181–0.958) | 0.039 |
| Aspiration pneumonia | 0.405 (0.128–1.285) | 0.125 |
| Diabetes mellitus | 0.635 (0.373–1.083) | 0.096 |
| Chronic liver disease | 1.611 (0.931–2.788) | 0.088 |
| Immunocompromised | 1.731 (1.115–2.689) | 0.015 |
| APACHE II score | 1.032 (1.004–1.062) | 0.027 |
| Lung injury score | 0.596 (0.374–0.951) | 0.030 |
| ARDS duration before ECMO | 1.002 (1.001–1.003) | 0.001 |
| Mean PEEP from day 1 to 3 on ECMO | 0.942 (0.877–1.013) | 0.106 |
| Mean dynamic driving pressure from day 1 to 3 on ECMO | 1.052 (1.015–1.090) | 0.005 |
| Mean dynamic compliance from day 1 to 3 on ECMO | 0.971 (0.941–1.002) | 0.069 |
| Multivariate analysis | ||
| Immunocompromised | 1.957 (1.216–3.147) | 0.006 |
| APACHE II score | 1.039 (1.005–1.073) | 0.023 |
| ARDS duration before ECMO | 1.002 (1.000–1.003) | 0.029 |
| Mean dynamic driving pressure from day 1 to 3 on ECMO | 1.070 (1.026–1.116) | 0.002 |
APACHE Acute Physiology and Chronic Health Evaluation, ARDS acute respiratory distress syndrome, CI confidence interval, ECMO extracorporeal membrane oxygenation, ICU intensive care unit, PEEP positive end-expiratory pressure. Dynamic driving pressure: (peak inspiratory pressure—PEEP)