Rat multiple organ blocks: microsurgical technique of removal for ex vivo aerobic organ preservation using a fluorocarbon emulsion.

ABSTRACT

A multiple organ block (MOB) is composed of en bloc removed organs (heart, lungs, liver, pancreas, kidneys, and bowel), connected by the vascular system, of which blood circulation is maintained by the heart and oxygenation by the lungs under artificial ventilation. The aim of this study is the description of a surgical technique of MOB removal in the rat. Ninety-five MOBs were removed from Wistar rats. The rats were anesthetized, a tracheotomy was performed, and the cannula was connected to a pressure-regulated respirator. A colectomy was performed. Ureters, vena cava inferior, aorta, and bile duct were cannulated using an operative microscope. The vessels that joined the MOB to the carcass were tied or coagulated to make removal of the MOBs possible. Once removed, the MOBs were placed in a vaseline oil bath at 37 degrees C and the aorta and vena cava were connected to an accessory vascular circuit to stabilize arterious pressure. Success rate (ex vivo survival of more than 10 min) after the 30th attempt was 90% and after the 60th attempt was 95% (global success rate 82%). Ex vivo survival of MOBs at 37 degrees C ranged from 1 to 450 min. Rat MOBs allows us to study the normothermic preservation of all the organs susceptible of being transplanted in one single series of experiments. We showed that removal of rat MOBs is feasible. This microsurgical technique is codified. Rat MOBs are suitable if perfusion liquids are difficult to obtain or if a great number of experiments are required. As MOBs are composed of synergically functioning organs in the absence of striated muscle, bone, and nervous system, they also could be useful for physiologic and pharmacologic studies.