Abstract 19663: Failed Delayed Sternal Closure Following Neonatal Cardiac Surgery Predicted by High Mean Airway Pressure and Associated with Increased Post-operative Mortality
Background: Myocardial edema, increased lung water, and anasarca are common following neonatal cardiac surgery with cardiopulmonary bypass and amplify the risk of hemodynamic instability and inadequate ventilation following sternal closure. Delayed sternal closure (DSC) in the intensive care unit one or more days following surgery is a common strategy to mitigate this risk, but has been associated with increased risk of infection. In addition, failed DSC has previously been identified as a risk factor for mortality. This study sought to identify predictor variables and determine impact of failed DSC.
Methods: Records of all neonates undergoing DSC in the cardiac intensive care unit (CICU) following surgery with cardiopulmonary bypass between January 2008 and May 2013 were reviewed. Pre-operative, intra-operative and post-operative variables were compared for those patients who failed DSC versus those who did not. Continuous variables were compared utilizing Wilcoxon’s test and categorical variables using Fisher’s exact test.
Results: Of 256 neonates undergoing DSC in the CICU, 22 failed first attempt at DSC. No significant difference between the two groups was appreciated in age, weight, or bypass (cross clamp, circulatory arrest, and total) times. Comparing DSC failures to successes, significantly more failures: followed Stage I palliation (63% vs. 31%); occurred later (post-operative day 4.7 vs. 2.8, p = 0.009); and were proceeded by higher mean airway pressures (9 vs. 8 cm H2O, p = 0.04), peak inspiratory pressure (27 vs. 24, p = 0.002), and inotrope score (12.1 vs. 9.6, p = 0.06). There was no association with systolic blood pressure or lactate prior to DSC. Failed DSC was associated with increased duration of mechanical ventilation (41.6 vs 7.4 days, p < 0.001), length of ICU stay (44.3 vs 12.0 days, p < 0.001), and mortality (38 vs 3%, p < 0.001).
Conclusions: Mortality for patients who fail the first ICU attempt at delayed sternal closure is significantly higher than for those with successful sternal closure. Ventilatory pressures but not hemodynamic variables prior to DSC differed significantly between the two groups. First attempt at DSC was later in those who failed, suggesting that clinicians had a priori identified these patients as higher risk.
Author Disclosures: D. Massey: None. K.A. Williams: None. R.R. Thiagarajan: None. F. Pigula: None. C.K. Allan: None.
- © 2014 by American Heart Association, Inc.