Preoperative Trapped Lung Is Associated With Increased Mortality After Orthotopic Liver Transplantation

Trapped lung, characterized by atelectatic lung unable to reexpand and fill the thoracic cavity due to a restricting fibrous visceral pleural peel, is occasionally seen in patients with end-stage liver disease complicated by hepatic hydrothorax. Limited data suggest that trapped lung prior to orthotopic liver transplantation may be associated with poor outcomes.

What is the clinical significance of trapped lung in patients receiving orthotopic liver transplantation?

We performed a retrospective analysis of patients who underwent liver transplantation over an 8-year period. Baseline clinical characteristics and postoperative outcomes of adult patients with trapped lung were analyzed and compared to the overall cohort of liver transplant recipients and controls matched 3:1 based on age, sex, Model for End-Stage Liver Disease (MELD) score, and presence of pleural effusion.

Of the 1193 patients who underwent liver transplantation, we identified 20 patients (1.68%) with trapped lung. The probability of 1 and 2-year survival were 75.0% and 57.1%, compared to 85.6% and 80.4% (p = 0.02) in all liver transplant recipients and 87.9% and 81.1% (p = 0.03) in matched controls respectively. Patients with trapped lung had a longer hospital length of stay compared to the total liver transplant population (geometric mean 54.9 ± 8.4 vs. 27.2 ± 0.7 days, p ≤ 0.001), when adjusted for age and MELD score.

Patients with trapped prior to orthotopic liver transplantation have increased probability of mortality as well as increased health care utilization. This is a small retrospective analysis, and further prospective investigation is warranted.