DOES AN ADDITIONAL SOURCE OF PULMONARY BLOOD-FLOW ALTER OUTCOME AFTERA BIDIRECTIONAL CAVOPULMONARY SHUNT

Background The bidirectional cavopulmonary shunt has become an importa nt intermediate step in the treatment of pediatric patients with singl e ventricle physiology who are ultimately destined for palliative surg ery. We wanted to know whether there would be risks or benefits if an additional source of pulmonary blood flow was left after a bidirection al cavopulmonary shunt. Methods and Results We retrospectively reviewe d the medical and surgical records of all patients who underwent a bid irectional cavopulmonary shunt al the Children's Hospital of Wisconsin between January 1991 and December 1993. A total of 43 patients were i dentified. Anatomic diagnoses included double inlet left ventricle (14 patients), tricuspid atresia (8 patients), pulmonary atresia with int act septum (6 patients), single right ventricle (5 patients), hypoplas tic left heart (3 patients), unbalanced atrioventricular septal defect (3 patients), and other complex lesions (4 patients). We then divided the patients into two groups for purposes of analysis. Group 1 had on ly the cavopulmonary shunt as a source of pulmonary flow (22 patients) ; group 2 had an additional source of pulmonary flow (21 patients). Pa tient age at the time of cavopulmonary shunt ranged from 6 months to 1 2 years, with group 1 patients being younger (31 versus 45 months, P=. 05). Group 2 patients had higher postoperative central venous pressure s (17.8 versus 14.1 mm Hg, P<.001) and oxygen saturations (86% versus 81%, P<.001) than did group 1 patients. There was no statistical diffe rence between groups in the number of chest tube days or hospital days . There was 1 early death in group 1 related to severe ventricular dys function and 1 late death in group 2 related to sepsis. Five patients in group 2 were readmitted to the hospital for drainage of a large chy lothorax compared with none in group 1 (P<.02). Conclusions We conclud e that patients with an additional source of pulmonary blood flaw afte r bidirectional cavopulmonary shunt have higher postoperative central venous pressures, have higher oxygen saturations, and are at risk for the late development of a chylothorax.