ANALYSIS OF AIRWAY FUNCTION OF IMMATURE WHOLE LUNG TRANSPLANTS VERSUSMATURE LOBAR TRANSPLANTS

For the pediatric patient with end-stage lung disease in need of trans plantation, two potential donor options currently exist: size-matched immature whole lungs or reduced-size mature lobes. To determine which of these options provides superior long-term function, we studied airw ay mechanics in a chronic porcine model of pediatric lung transplantat ion. Three groups of animals were studied: the first group underwent l eft upper lobectomy at 9 +/- 1 weeks of age (innervated left lower lob es). These animals served as controls. A second group of 9-week-old an imals received an immature whole left lung allograft from age-matched donors. The third group received a reduced-size mature left lower lobe from 6-month-old donors. Measurements of dynamic airway resistance, p ulmonary compliance, and functional residual capacity of the isolated lobes or lungs, and of the nonoperated right lungs, were recorded 12 /- 1 weeks later, and mean values were calculated for each group. Resu lts showed that transplantation of an immature whole lung resulted in abnormal dynamic airway resistance to airflow, which was not seen in t he mature lobar transplants. In addition, compliance was impaired most significantly in the immature whole lung transplants. We conclude tha t in this experimental model of pediatric lung transplantation, transp lantation of a mature lobar segment results in superior long-term airw ay function when compared with immature whole lung transplants.