OPERATIVE STRATEGIES AND BLTX VS HLTX
The standard surgical approach for patients with PH is bilateral lung transplantation under cardiopulmonary bypass. Heart-lung transplantation is usually only performed in patients with PH and irreparable cardiac defect 16. Furthermore, heart-lung blocs have been increasingly rare in the USA with seven or fewer heart-lung transplants performed in the pediatric age group in each of the last ten years (UNOS.org reference). Furthermore, clinical experience has shown good recovery of cardiac function in virtually all infants, children and adolescents with severe PH who survive the early post-operative period. Single lung transplant is rarely performed in pediatrics, particularly for patients with PH due to adverse outcomes like pulmonary edema and graft dysfunction 17.
Cardiopulmonary bypass (CPB) is used in pediatric patients due to challenges utilizing double lumen endobronchial tubes in small airways to provide single lung ventilation 17. As well, in PH patients, CPB provides hemodynamic stability in presence of increased pulmonary vascular resistance (PVR) 18. In some adult transplant centers, ECMO has become the preferred intra-operative support as it is associated with reduced complications and improved survival 19. ECMO can also be extended post-operatively to support patients either to prevent or in selected patients with significant graft dysfunction 20.