Donor prone positioning protects lungs from injury during warm ischemia

Abstract

Abbreviations: CBCT, C-arm cone-beam computed tomography; cDCD, controlled donation after circulatory death; Cdyn, dynamic compliance; CSP, cold static preservation; Csta, static compliance; DBD, donation after brain death; ELISA, enzyme-linked immunosorbent assay; EVLP, ex vivo lung perfusion; IL, interleukin; PawP, peak airway pressure; PEEP, positive end-expiratory pressure; Pplat, airway plateau pressure; PVR, pulmonary vascular resistance; TUNEL, terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling; WDR, wet-to-dry weight ratio; WIT, warm ischemic time; WLST, withdrawal of life-sustaining therapy; ZO-1, Zonula occludens protein-1.A large proportion of controlled donation after circulatory death (cDCD) donor lungs are declined because cardiac arrest does not occur within a suitable time after the withdrawal of life-sustaining therapy. Improved strategies to preserve lungs after asystole may allow the recovery team to arrive after death actually occurs and enable the recovery of lungs from more cDCD donors. The aim of this study was to determine the effect of donor positioning on the quality of lung preservation after cardiac arrest in a cDCD model. Cardiac arrest was induced by withdrawal of ventilation under anesthesia in pigs. After asystole, animals were divided into 2 groups based on body positioning (supine or prone). All animals were subjected to 3 hours of warm ischemia. After the observation period, donor lungs were explanted and preserved at 4°C for 6 hours, followed by 6 hours of physiologic and biological lung assessment under normothermic ex vivo lung perfusion. Donor lungs from the prone group displayed significantly greater quality as reflected by better function during ex vivo lung perfusion, less edema formation, less cell death, and decreased inflammation compared with the supine group. A simple maneuver of donor prone positioning after cardiac arrest significantly improves lung graft preservation and function. K E Y W O R D Sanimal models: porcine, basic (laboratory) research/science, donors and donation: donation after circulatory death (DCD), donors and donation: extended criteria, lung transplantation/ pulmonology, organ perfusion and preservation, organ procurement, organ procurement and allocation, translational research/science

Lung donation after circulatory death

“…After 3 hours of WIT, 6 hours of cold preservation and 6 hours of normothermic machine perfusion, the results show a better tolerance to WIT, less atelectasis and apoptosis in the prone positioned group. These results confirmed once again the importance of ventilation in lung preservation (8). Great interest has always been given to the intrapulmonary thrombi formation after lung procurement from DCD and subsequent reperfusion injury.…”

Initial lung transplantation experience with uncontrolled donation after cardiac death in North America

“…To that end, we recently modified our protocol to allow for lung inflation 15 minutes after death declaration. We also adopted the measure of proning donors early after death as this maneuver has demonstrated marked benefits in a preclinical translational DCD model . Our recent preliminary data are promising, but the real impact of these maneuvers in increasing lung utilization is still to be determined.…”

Ex vivo lung perfusion

“…Prone positioning has shown beneficial effects for patients with lung injury (83). Prone positioning also improved graft function in a pig DCD EVLP model (84). Niikawa et al tested the role of prone positioning of lungs on EVLP and demonstrated better oxygenation and lung compliance, lower weight ratio, and lower IL-1β levels in prone position lungs compared to control lungs in supine position (67).…”