Table 6.
Multivariable Cox Proportional Hazards Model
| Predictor | Univariable Model | Multivariable Model | ||
|---|---|---|---|---|
| HR (95% CI) | P Value | HR (95% CI) | P Value | |
| Race, white vs other | 1.00 (0.67, 1.51) | 0.990 | ··· | ··· |
| Birth weight, kg | 1.36 (1.10, 1.67) | 0.005 | 1.36 (1.06, 1.60) | 0.011 |
| Pulmonary valve anatomy | ||||
| Atresia vs stenosis | 0.50 (0.32, 0.79) | 0.003 | 0.53 (0.39, 1.04) | 0.036 |
| Absent vs stenosis | 0.26 (0.08, 0.82) | 0.021 | 0.28 (0.08, 0.97) | 0.044 |
| Aortopulmonary collaterals | 0.49 (0.28, 0.87) | 0.016 | 0.44 (0.24, 0.84) | 0.018 |
| Number of CPB runs, >1 vs 1 | 0.42 (0.24, 0.74) | 0.003 | 0.34 (0.19, 0.63) | 0.001 |
| Total aortic cross‐clamp time (10‐min increase) | 0.89 (0.84, 0.95) | 0.001 | 0.88 (0.79, 0.97) | 0.009 |
| Use of DHCA | 0.56 (0.30, 1.03) | 0.063 | 0.74 (0.31, 1.75) | 0.491 |
| Lowest hematocrit on CPB | 1.06 (1.02, 1.10) | 0.002 | 1.05 (0.99, 1.10) | 0.097 |
| Neonatal vs nonneonatal repair | 0.54 (0.35, 0.85) | 0.008 | 0.52 (0.31, 0.85) | 0.010 |
Results from the Cox proportional hazards models adjusting for surgeon are reported as hazard ratios with 95% confidence intervals. These covariates explain 41% of the variability in time to hospital discharge. Postoperative variables were excluded, as they are collinear with the outcome. CI indicates confidence interval; CPB, cardiopulmonary bypass; DHCA, deep hypothermic circulatory arrest; HR, hazard ratio.