Size disparity in pediatric lung transplantation

Donor scarcity and the limitations of organ preservation dictate that a wide size range be used to maximize effective donor utilization in pulmonary transplantation. Problems of size disparity are magnified in the pediatric population, where relevant dimensions vary considerably by age. There have been 10 pediatric lung recipients (7 bilateral, 2 single, 1 heart-lung) at our institution since 1991. The age range was 3 to 26 years (mean, 13.7), and the weight range was 15 to 57 kg (mean, 33.6). Diagnoses included cystic fibrosis (5), pulmonary fibrosis (2), pulmonary hypertension (2), and arteriovenous malformation (1). The donor-to-recipient weight ratio ranged from 0.45 to 1.9, and the donor-to-recipient thoracic height ratio ranged from 0.6 to 1.6. Lobar resection and delayed chest closure was required in one case and was successful. Cardiopulmonary bypass was used electively in seven cases. No reexplorations for bleeding were necessary. Two of the three hospital deaths resulted from right ventricular failure, judged to be secondary to excessive pulmonary artery pressures intraoperatively associated with small donor allografts. Elective bypass had not been used. Inhaled nitric oxide (6 patients) and/or extracorporeal membrane oxygenation (2 patients) were used for temporary postoperative support. The hospital survival rate was 70% (7/10). One late death occurred 14 months postoperatively and was caused by obliterative bronchiolitis. The authors conclude that size disparity is a significant problem in pediatric lung transplantation. However, with elective use of cardiopulmonary bypass and aggressive postoperative support, a broad size range can be used.