Nicholas Robbins1, Kevin Y Wu1, Renford Cindass2, Sharon Lawson3, Lin Wang2, George E Wolf1, Michael Davis, MD1. 1RESTOR™ Program, 59th Medical Wing, JBSA Lackland AFB, TX, 2San Antonio Military Medical Center, JBSA Fort Sam Houston, TX, 3University of Texas Health Sciences Center at San Antonio
Objective: Modern body armor, rapid evacuation and advanced combat casualty care have improved survival after catastrophic extremity and maxillofacial trauma. Vascularized composite allotransplantation (VCA) is a superior restorative option compared to traditional reconstruction in these complex injuries. To mitigate obligate reperfusion injury in VCA, we evaluate the efficacy of a novel normothermic hyperbaric oxygen warm ex-vivo perfusion strategy using hyperoxygenated University of Wisconsin (UW) solution in a porcine VCA model.
Methods: Gracilis myocutaneous flap autotransplants were performed heterotopically in the cervical area of Yorkshire swine. Group 1 (controls, n=5) flaps were perfused with cold UW at 4ºC for three hours prior to transplant. Group 2 (experimental, n=2) flaps were perfused with hyper-oxygenated UW for seven hours at 37ºC in a hyperbaric chamber at 3 atm before transplantation. Flaps were monitored daily for clinical evidence of viability and biopsied per protocol with an end point of 21 days. Histologic analysis was blinded.
Results: Autotransplants remained viable at the 21 day end point. Histological evaluation revealed extensive diffuse evidence of necrosis in all controls (at 3 hours, cold static preservation) but flaps placed on hyperbaric ex-vivo perfusion support showed decreased histologic evidence of ischemic injury or necrosis ranging from rare to moderate.
Conclusion: Hyperbaric normothermic perfusion dramatically extends the viability of composite tissues ex-vivo. Injuries secondary to ischemia and cold preservation are mitigated. This technology has the potential to extend the window of time between procurement and transplantation in the growing field of Reconstructive Transplantation as well as solid organ transplants. Such innovations would dramatically expand the donor pool and provide options for superior matches to transplant candidates.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 79756
Program Number: MSS12
Presentation Session: Full-Day Military Surgical Symposium – Basic Science Presentations
Presentation Type: MSSPodium