A simplified preservation method for lungs donated after cardiac death.

UNLABELLED: The shortage of donor lungs restricts the number of lung transplantations that can be performed. However, extension of the donor pool using organs donated after cardiac death (DCD) could potentially increase the number of patients who undergo transplantation. To establish acceptance among hospital personnel and the donor's next of kin for the uncontrolled DCD procedure we proposed a simplified preservation regime for intrapleural cooling of the donor lungs. METHODS: In an uncontrolled DCD model, 12 pigs were randomized to intrapleural lung cooling using either a standard method with two bilateral chest tubes and intermittent pleural fluid exchanges, or a simplified, less-invasive method with a single bilateral chest tube and filling of the pleural space without fluid exchange. Lungs were explanted and graft function was assessed during ex vivo lung perfusion (EVLP) and by histologic examination. RESULTS: Although the mean temperature after 120 minutes of intrapleural cooling was significantly higher in the lungs cooled using the simplified method (25.9°C vs 13.5°C), this did not affect the oxygenation capacity, pulmonary vascular resistance or dynamic compliance of the lungs, as recorded during EVLP. Furthermore, no differences were found between the lungs preserved by the two methods with respect to the wet/dry ratio, levels of myeloperoxidase in bronchoalveolar lavage, or at histologic examination. CONCLUSIONS: The simplified technique for DCD lung cooling results in a higher preservation temperature but does not affect lung function during EVLP, which implies that this less invasive method can be used in the uncontrolled DCD setting. This is another step forward in the development of a simplified preservation routine for DCD.

Heparin does not improve graft function in uncontrolled non-heart-beating lung donation: an experimental study in pigs.

OBJECTIVES: Non-heart-beating donation (NHBD) has the potential to increase the number of patients treated with lung transplantation. Our study investigated, in a simulated clinical situation in the uncontrolled NHBD setting, whether or not heparin administration after death affects the donor lung function. METHODS: Twelve Swedish domestic pigs underwent ventricular fibrillation and were left untouched for 7 min followed by cardiopulmonary resuscitation with mechanical compressions for 20 min. The animals were declared dead after a 'hands-off' period of 10 min and randomized to heparin (300 IU/kg) or placebo given into a central venous catheter. In the animals receiving heparin, 2 more minutes of chest compression followed. Intrapleural cooling was initiated 1 h after death, and prevailed for 2 h. Ex vivo lung perfusion (EVLP) was performed with the Vivoline(®) system. Lung function was evaluated with blood gases at different oxygen levels, pulmonary vascular resistance (PVR), wet/dry weight ratio, macroscopic appearance and histology. RESULTS: During EVLP, there were no significant differences between groups in PaO(2) or PVR at any investigated FiO(2) level (1.0, 0.5 or 0.21). At FiO(2) 1.0 the PaO(2) in the heparin group was 64 ± 2 (range 57-73) kPa and in the non-heparin group 63 ± 4 (range 51-71) kPa. The values for PVR were 592 ± 90 (range 402-1007) and 647 ± 97 (range 426-1044), respectively. There was no significant difference between groups in wet/dry ratio or histology. CONCLUSIONS: The use of heparin is of no obvious benefit to the donor lungs in the uncontrolled NHBD situation. The exclusion of heparin will simplify lung donation from NHBDs.