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.

Background.: Abdominal wall closure after transplantation is crucial to reduce morbidity and to ensure graft and patient survival, but it often remains challenging. Donor nonvascularized rectus fascia (NVRF) allotransplantation offers a valuable solution when primary closure fails. Despite the growing clinical use of NVRF, standardized protocols for NVRF preservation are lacking. This study evaluates the impact of short-term cold storage at 4 °C (8 d) and long-term cryopreservation (1 mo and 6 mo) on human NVRF at the mechanical, histological, and microbiological levels. Methods.: NVRF was obtained from 10 human donors (6 men; 6 donation after circulatory death III; 4 donation after brain death; age 56 y [26–68 y]; BMI 28 kg/m ² [23–31 kg/m ² ]). Fresh tissue was compared with 3 preservation methods: (1) cold storage in Institute Georges Lopez-1 solution at 4 °C for 8 d; (2) 1 mo cryopreservation; and (3) 6 mo cryopreservation at –80 °C. For each condition, the analysis included uniaxial tensile testing, histological evaluation based on hematoxylin and eosin and picrosirius red staining, and microbiological analysis for yeast and bacteria. Results.: After 8 d at 4 °C, ultimate strength and rigidity were reduced, whereas histological structure appeared intact. One month of cryopreservation showed no indications for altered mechanical or histological characteristics compared with fresh tissue. After prolonged cryopreservation for 6 mo, extensibility was increased. Yeast contamination was absent in all samples, and commensal bacteria were detected in 17 of 40 fresh and preserved samples, without impact of the preservation method. Conclusions.: In conclusion, cryopreservation at –80 °C maintains biomechanical characteristics and structural integrity of NVRF for up to 1 mo, offering a promising method for prolonged NVRF preservation in clinical applications.

Static ice storage (SIS) is the historic standard for lung preservation. It has been assumed that SIS results in 4°C organ temperatures. However, no prior studies measured lung temperature during SIS, potentially reaching near-freezing conditions. We aimed to measure lung and preservation temperature dynamics with SIS in porcine experiments and clinical observations. Methods: Porcine lungs were preserved with SIS for 8h (group I, n=3) and 3h followed by 10°C storage (group II, n=3). Tissue (tissueT°), 1st bag preservation solution (psT°) and 2nd 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 4h in group I, average tissueT° was 0.66°C, psT° was 0.12°C, salineT° was -0.02°C. After 3h in group II, average tissueT° was 1.90°C, psT° was 0.57°C, salineT° was 2.33°C. In clinical observations, psT° was below 4°C after 9-13min and 0°C after 78-267min. After SIS, median surfaceT° was 1.25°C (min-max; -3.2°C – 9.2°C) , and coreT° was 1.45°C (-0.4°C – 4.8°C). Conclusions: SIS leads to rapid temperature drops below 4°C, approaching 0°C within 2-4 hours. 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.