Renal circulatory occlusion and local cooling

¹ University Institute for Experimental Medical Research, Ullevål Hospital, Oslo, Norway

A method was developed for local kidney cooling in vivo, evaluated in dogs and applied clinically. In dogs a reversible lesion was not obtained if renal ischemia lasted beyond 1 hour at 37°C. Application of local cooling (10±5°C) extended the tolerance time to 7 hours, with clamping of the entire renal pedicle, and to 12 hours with occlusion of the renal artery alone. Exposure of the same kidney to a second occlusion period (up to 9 hr.) resulted in a reversible lesion. Renal function studies (C_U, C_In, C_PAH and TmPAH) showed the same pattern (initial depression and course of recovery) as after renal ischemia at body temperature. Initial depression was roughly paralleling the duration of clamping. Preischemic function values were, in most instances, reached 3 months following the experimental procedure. Physiological aspects of ‘local cooling’ are discussed and the advantages over general hypothermia are pointed out. The technique used for clinical application is described.