CT Volumetry Versus Body Plethysmography in Measuring TLC in Lung Transplantation

Chest X-ray Sizing for Lung Transplants Reflects Pulmonary Diagnosis and Body Composition and Is Associated With Primary Graft Dysfunction Risk

BACKGROUND

Donor-recipient oversizing based on predicted total lung capacity (pTLC) is associated with a reduced risk of primary graft dysfunction (PGD) following lung transplant but the effect varies with the recipient's diagnosis. Chest x-ray (CXR) measurements to estimate actual total lung capacity (TLC) could account for disease-related lung volume changes, but their role in size matching is unknown.

METHODS

We reviewed adult double lung transplant recipients 2007-2016 and measured apex-to-costophrenic-angle distance (=lung height) on pretransplant donor and recipient CXRs (oversized donor-recipient ratio >1; undersized ≤1]. We tested the relationship between recipient lung height to actual TLC; between lung height ratio and donor/recipient characteristics; and between both lung height ratio or pTLC ratio and grade 3 PGD with logistic regression.

RESULTS

Two hundred six patients were included and 32 (16%) developed grade 3 PGD at 48 or 72 hours. Recipient lung height was related to TLC (r2=0.7297). Pulmonary diagnosis, donor BMI, and recipient BMI were the major determinants of lung height ratio (AUC 0.9036). Lung height ratio oversizing was associated with increased risk of grade 3 PGD (odds ratio, 2.51; 95% confidence interval, 1.17-5.47; P = 0.0182) in this cohort, while pTLC ratio oversizing was not.

CONCLUSIONS

CXR lung height estimates actual TLC and reflects pulmonary diagnosis and body composition. Oversizing via CXR lung height ratio increased PGD risk moreso than pTLC-based oversizing in our cohort.