Forty-Eight Hour Ex Vivo Perfusion and Two-Hour Simulated Reperfusion after a Major Traumatic Upper Extremity Amputation

Abstract

Background Extremity replantation as well as allotransplantation aim to restore form and function of the amputated limb. Both approaches, however, are clearly limited by the ischemic time. Ex vivo perfusion (EVP), already well-established in the field of solid organ transplantation, represents a promising tool to overcome this restriction. Methods We have currently established the technical requirements to provide EVP to severed limbs in a clinical hospital setting and hereby report of a 48-hour hypothermic EVP (EVP48) of an upper extremity amputated at the level of the proximal humerus, followed by a 2-hour simulated reperfusion (2SR) with donor blood. Results Muscle biopsies revealed histopathologically well preserved, vital muscle tissue after EVP24, and partially grouped muscle fiber necrosis with predominantly vital muscle tissue after EVP48 and 2SR. Analyses of perfusate samples showed a marked decline of biochemical muscle damage markers during EVP48. Cytokine analysis disclosed an isolated increase of the proinflammatory cytokines, interleukine-6, monocyte chemotactic protein-1, and interferon-γ, during EVP and 2SR. Magnetic resonance imaging, performed after EVP48, indicated partial muscle necrosis of the intrinsic hand muscles only, while no signs for infection or inflammation were present. Conclusion Our single case experience shows the general feasibility of an amputated limb ex vivo salvage perfusion setting to allow for delayed replantation up to 24 hours. Nevertheless, an accurate prior planning is crucial to ensure successful implementation of EVP in the acute clinical setting.

Keywords

• ex vivo perfusion
• extremity
• amputation
• replantation