Ceulemans, Laurens J

Background: Static ice storage (SIS) has long been accepted as the conventional lung preservation method, assuming to maintain 4 °C temperature. Although never directly confirmed by temperature measurements, this assumption has been widely accepted. We aimed to measure lung and preservation temperature with SIS in porcine experiments and clinical observations. Methods: Porcine lungs were preserved with SIS for 8 h (group I, n = 3) and 3 h followed by 10 °C storage (group II, n = 3). Tissue (tissueT°), first bag preservation solution (psT°) and second bag saline (salineT°) temperature were monitored. In clinical lungs (n = 4), psT° was monitored during SIS. Surface (surfaceT°) and core (coreT°) temperature were assessed before and after SIS (n = 62). Results: After 4 h in porcine lung group I, average tissueT° was 0.66 °C, psT° was 0.12 °C and salineT° was −0.02 °C. After 3 h in group II, average tissueT° was 1.90 °C, psT° was 0.57 °C and salineT° was 2.33 °C. In clinical observations, psT° was below 4 °C after 9–13 min and 0 °C after 78–267 min. After SIS, median surfaceT° was 1.25 °C (min-max; −3.2–9.2 °C) and coreT° was 1.45 °C (−0.4–4.8 °C). Conclusions: SIS leads to rapid temperature drops below 4 °C, approaching 0 °C within 2–4 h. The post-SIS lung temperature shows considerable variability and does not consistently remain at the commonly assumed 4 °C, posing potential freezing injury to donor lungs.

ABSTRACTIntroductionLung transplantation has become increasingly utilized in patients with COVID‐19. While several single‐center and UNOS database studies have been published on lung transplants (LTs) for end‐stage lung disease (ESLD) from Coronavirus disease 2019 (COVID‐19), there is a lack of multi‐center and international data.MethodsThis is a multicenter analysis from 11 high‐volume lung transplant centers in the United States and Europe. Data were collected through the Multi‐Institutional ECLS Registry and stratified by ESLD due to COVID‐19 versus other etiologies. Demographics and clinical variables were compared using Chi‐square test and Fisher's exact test. Survival was assessed by Kaplan‐Meier curves and compared by log‐rank test with propensity score matching.ResultsOf 1606 lung transplant recipients, 46 (2.9%) were transplanted for ESLD from COVID‐19 compared to 1560 (97.1%) without a history of COVID‐19. Among COVID‐19 patients, 30 (65.2%) had COVID‐19‐associated ARDS and 16 (34.8%) had post‐COVID‐19 fibrosis. COVID‐19 patients had higher lung allocation scores (78.0 vs. 44.4, p < 0.0001), had severely limited functional status (37.0% vs. 2.9%, p < 0.0001), had higher preoperative ECMO usage (65.2% vs. 5.4%, p < 0.0001), and spent less time on the waitlist (32 vs. 137 days, p < 0.0001). A 30‐day survival was comparable between COVID‐19 and non‐COVID‐19 patients before (100% vs. 98.7%, p = 0.39) and after propensity matching (p = 0.15).ConclusionsPatients who received LTs due to COVID‐19 had short‐term survival comparable to that of patients without COVID‐19. Our findings support the idea that lung transplantation should be considered for select patients with ESLD due to COVID‐19.