Related Experiment Video
Updated: Mar 7, 2026
Procurement and Decellularization of Rat Hindlimbs Using an Ex Vivo Perfusion-Based Bioreactor for Vascularized Composite Allotransplantation
Published on: June 9, 2022
Ex Situ Perfusion of Human Limb Allografts for 24 Hours
Nicole L Werner1, Fares Alghanem, Stephanie L Rakestraw
11 Department of Surgery, The University of Michigan Health System, Ann Arbor, MI.2 Department of Orthopedic Surgery, The University of Michigan Health System, Ann Arbor, MI.3 Gift of Life of Michigan, Ann Arbor, MI.4 Lung Bioengineering United Therapeutics Corporation, Silver Spring, MD.5 Section of Transplant Surgery, Department of Surgery, The University of Michigan Health System, Ann Arbor, MI.
Background:
Vascularized composite allografts, particularly hand and forearm, have limited ischemic tolerance after procurement. In bilateral hand transplantations, this demands a 2 team approach and expedited transfer of the allograft, limiting the recovery to a small geographic area. Ex situ perfusion may be an alternative allograft preservation method to extend allograft survival time. This is a short report of 5 human limbs maintained for 24 hours with ex situ perfusion.
Methods:
Upper limbs were procured from brain-dead organ donors. Following recovery, the brachial artery was cannulated and flushed with 10 000 U of heparin. The limb was then attached to a custom-made, near-normothermic (30-33°C) ex situ perfusion system composed of a pump, reservoir, and oxygenator. Perfusate was plasma-based with a hemoglobin concentration of 4 to 6 g/dL.
Results:
Average warm ischemia time was 76 minutes. Perfusion was maintained at an average systolic pressure of 93 ± 2 mm Hg, flow 310 ± 20 mL/min, and vascular resistance 153 ± 16 mm Hg/L per minute. Average oxygen consumption was 1.1 ± 0.2 mL/kg per minute. Neuromuscular electrical stimulation continually displayed contraction until the end of perfusion, and histology showed no myocyte injury.
Conclusions:
Human limb allografts appeared viable after 24 hours of near-normothermic ex situ perfusion. Although these results are early and need validation with transplantation, this technology has promise for extending allograft storage times.
