Risk factors for persistent pleural effusions after the extracardiac Fontan procedure

Objective: Pleural effusions after the Fontan operation contribute significantly to morbidity and prolonged hospitalization. This study investigates the association between selected preoperative, operative, and postoperative variables and persistent pleural effusions after the extracardiac Fontan procedure. Methods: We conducted a retrospective study of extracardiac Fontan procedures. The variables analyzed as potential risk factors included age and weight at the time of the operation, anatomic diagnosis, preoperative oxygen saturation, mean pulmonary artery pressure, ventricular end-diastolic pressure, presence of an accessory source of pulmonary blood flow, presence of significant aortopulmonary collateral vessels, presence of fenestration, cardiopulmonary bypass time, conduit size, postoperative pulmonary artery pressure, use of angiotensin-converting, enzyme inhibitors, and presence of postoperative infection. The outcome measures evaluated were duration and volume of chest tube drainage after surgical intervention. Results: From June 1997 to August 2002, 100 consecutive patients underwent the extracardiac Fontan procedure. The median age at operation was 3.1 years. The median duration of chest tube drainage was 10 days, and the median volume of drainage was 14.7 mL . kg(-1) . d(-1). As determined by means of multivariate analysis, significant risk factors for pleural effusions lasting more than 2 weeks were lower preoperative oxygen saturation (P = .011) and the presence of postoperative infections (P = .003). Significant risk factors for pleural effusions draining at more than 20 mL . kg(-1) . d(-1) were lower preoperative oxygen saturation (P = .005), smaller conduit size (P = .04), and longer duration of cardiopulmonary bypass (P = .004). Conclusions: Lower preoperative oxygen saturation, presence of postoperative infection, smaller conduit size, and longer duration of cardiopulmonary bypass were associated with persistent pleural effusions after the extracardiac Fontan procedure. Modifications of some of these risk factors might influence the duration and volume of pleural drainage after surgical intervention.