Postoperative Respiratory Failure in Children With Tetralogy of Fallot, Pulmonary Atresia, and Major Aortopulmonary Collaterals

Abstract

Children with tetralogy of Fallot, pulmonary atresia, and major aortopulmonary collaterals (TOF/PA/MAPCAs), who undergo unifocalization surgery are at risk for prolonged postoperative respiratory failure. We sought to identify risk factors that are associated with prolonged mechanical ventilation in this population. We collected preoperative and operative data from medical records and postoperative data prospectively. Mechanical ventilation beyond postoperative day 5, which was greater than the 50th percentile for the subjects enrolled, was considered prolonged. Risk factors were analyzed using multiple logistic regression, independent samples t test, Fisher's exact test, and Kruskal-Wallis test. Enrollment occurred over a 20-month period between May 2009 and January 2011. Lucile Packard Children's Hospital (Palo Alto, CA). All patients with TOF/PA/MAPCAs presenting for unifocalization or pulmonary artery revision procedures were eligible, including those with additional structural cardiac abnormalities requiring surgical intervention. We excluded patients with single-ventricle cardiac anatomy and preoperative respiratory failure or infection. We enrolled 35 consecutive patients undergoing 37 procedures over the study period. One patient was excluded for single-ventricle anatomy. There were 12 cases (32%) of prolonged mechanical ventilation. Delayed sternal closure was the only risk factor associated with prolonged mechanical ventilation (p = 0.01). Age, weight, cardiopulmonary bypass time, 22q11 microdeletion, postoperative fluid balance, bronchospasm, and nonrespiratory infection were not significantly associated with prolonged mechanical ventilation. Respiratory complications occurred in both groups, and patients with pneumonia were more likely to have a prolonged course (p = 0.03). There was no significant association between the type of surgery performed and duration of mechanical ventilation. Prolonged postoperative respiratory failure in children undergoing surgery for TOF/PA/MAPCAs was independently associated with delayed sternal closure. Respiratory complications occur after unifocalization surgery, and pneumonia is associated with prolonged mechanical ventilation. Our pilot study suggests that clinical features common in this patient population, such as bronchospasm and 22q11 microdeletion, were not associated with more postoperative respiratory failure.