Size matching in lung transplantation using predicted total lung capacity

Area of Science:

• Thoracic surgery
• Pulmonary medicine
• Transplant immunology

Background:

• Donor lung allocation currently relies on height as an indirect measure of thoracic size.
• Total lung capacity (TLC), influenced by height and sex, offers a potentially more accurate functional thoracic size estimate.
• The impact of size-matching criteria on post-lung transplant outcomes requires further investigation.

Purpose of the Study:

• To retrospectively evaluate size-matching criteria based on height versus predicted TLC in lung transplantation.
• To determine if TLC mismatch, influenced by donor-recipient height and sex disparities, correlates with clinical and functional complications.
• To assess the clinical implications of using height alone versus predicted TLC for donor lung allocation.

Main Methods:

• Retrospective analysis of 80 bilateral lung transplant recipients.
• Calculation of donor-to-recipient height ratios and predicted TLC ratios.
• Evaluation of complications including atelectasis, pneumothorax, intensive care unit (ICU) stay, bronchiolitis obliterans syndrome (BOS), and exercise capacity limitation.

Main Results:

• Median donor/recipient height ratio was 1.01 (range: 0.93-1.12).
• Median predicted TLC donor/recipient ratio was 1.01 (range: 0.72-1.41), indicating a wider variability than height ratio.
• No significant association was found between sex mismatch, TLC mismatch, and the evaluated clinical or functional complications.

Conclusions:

• Donor lung allocation based solely on height can result in significant TLC mismatches, particularly due to sex differences.
• The study suggests that current height-based allocation may be overly restrictive, as TLC mismatch did not correlate with adverse outcomes.
• A wider range of donor-recipient height discrepancies may be acceptable in lung allocation without compromising patient outcomes.