Background: Currently, severed limbs after combat or traumatic injuries are preserved with cold ischemic storage. However, this method maintains limb viability for no more than 12 hours. In this study, a new device, referred to as the Universal Limb Stasis System for Extended Storage (ULiSSES™), was used to maintain rodent skeletal muscle viability for 24 hours, after 4 hours of ambient temperature ischemia.
Methods: Hind-limbs from 5 Sprague Dawley rats were recovered and allowed to lie on a counter for approximately 4 hours at room temperature (19-24°C) to simulate delayed limb recovery. Limbs were then perfused for 24 hours using room temperature Krebs Henseleit solution. Arterial and venous pressure, flow, PaO2, PvO2, perfusate pH, and temperature were recorded hourly.
Results: Ambient ischemia time was 3.4 ± 0.5 hours. Perfusion pressure was 8.2 ± 2.0 mmHg with a mean flow to the limbs of 9.5 ± 5.0 ml/min. The pH and temperature of the KH perfusate were stable throughout preservation at 7.38 ± 0.05 and 23.7 ± 0.5ºC, respectively. Oxygen consumption reached a plateau of 0.28 ± 0.04 ml O2/min/100 g by 17 hours with vascular resistance hovering around 1.0 ± 0.2 mmHg/ml/min initially, then declining by about 50% after 18 hours. Mean limb weight gain was 37.7 ± 31.8%.
Conclusions: ULiSSES™ appears to open the potential for stabilization and preservation of avulsed limbs for 24 hours or longer, leading to the feasibility of costeffective transport from any recovery site to any re-plantation site with minimal tissue deterioration.