Lung Size Mismatch in Bilateral Lung Transplantation Is Associated With Allograft Function and Bronchiolitis Obliterans Syndrome

• Published in: Chest Vol. 141; no. 2; pp. 451 - 460
• Main Authors: Eberlein, Michael, MD, PhD, Permutt, Solbert, MD, Chahla, Mayy F., MD, Bolukbas, Servet, MD, PhD, Nathan, Steven D., MD. FCCP, Shlobin, Oksana A., MD, FCCP, Shelhamer, James H., MD, FCCP, Reed, Robert M., MD, Pearse, David B., MD, Orens, Jonathan B., MD, Brower, Roy G., MD
• Format: Journal Article
• Language: English
• Published: Northbrook, IL American College of Chest Physicians 01-02-2012
• Subjects: Adult; Analysis of Variance; Antithrombotic Therapy; Biological and medical sciences; Bronchiolitis Obliterans - etiology; Cardiology. Vascular system; Chronic obstructive pulmonary disease, asthma; Female; Humans; Least-Squares Analysis; Lung - anatomy & histology; Lung Transplantation; Male; Medical sciences; Organ Size; Pneumology; Postoperative Complications - etiology; Proportional Hazards Models; Pulmonary/Respiratory; Respiratory Function Tests; Retrospective Studies; Incompatibility; Respiratory disease; Lung; Size; Bilateral; Transplantation; Homotransplantation; Syndrome; Treatment; Surgery; Graft; Bronchus disease; Anesthesia; Bronchiolitis obliterans; Circulatory system; Cardiology
• ISSN: 0012-3692; 1931-3543
• DOI: 10.1378/chest.11-0767

Background Size mismatch between donor lungs and a recipient thorax could affect the major determinants of maximal expiratory airflow: airway resistance, propensity of airways to collapse, and lung elastic recoil. Methods A retrospective review of 159 adults who received bilateral lung transplants was performed. The predicted total lung capacity (pTLC) for donors and recipients was calculated based on sex and height. Size matching was represented using the following formula: pTLC ratio = donor pTLC / recipient pTLC. Patients were grouped according to those with a pTLC ratio > 1.0 (oversized) or those with a pTLC ratio ≤ 1.0 (undersized). Allograft function was analyzed in relation to the pTLC ratio and to recipient and donor predicted function. Results The 96 patients in the oversized cohort had a mean pTLC ratio of 1.16 ± 0.13 vs 0.89 ± 0.09 in the 63 patients of the undersized group. At 1 to 6 months posttransplant, the patients in the oversized cohort had higher FEV1 /FVC ratios (0.895 ± 0.13 vs 0.821 ± 0.13, P < .01) and lower time constant estimates of lung emptying (0.38 ± 0.2 vs 0.64 ± 0.4, P < .01) than patients in the undersized cohort. Although the FVCs expressed as % predicted for the recipient were not different between cohorts, the FVCs expressed as % predicted for the donor organ were lower in the oversized cohort compared with the undersized cohort (at 1-6 months, 52.4% ± 17.1% vs 65.3% ± 18.3%, P < .001). Kaplan-Meier estimates for the occurrence of bronchiolitis obliterans syndrome (BOS) showed that patients in the oversized cohort had a lower probability of BOS ( P < .001). Conclusions A pTLC ratio > 1.0, suggestive of an oversized allograft, is associated with higher expiratory airflow capacity and a less frequent occurrence of BOS.