Influence of anesthetic variables on short-term and overall survival rates in cats undergoing renal transplantation surgery

Objective—To identify factors associated with short-term (30-day) and overall survival rates in cats that underwent renal transplantation surgery (RTS). Design—Retrospective cohort study. Animals—94 cats that underwent RTS from 1998 through 2010. Procedures—Data obtained from the medical records pertinent to RTS included cat signalment; anesthetic agents, techniques, and timings; supportive treatment; perioperative physiologic findings; and surgery and warm ischemia times. Associations with short-term and overall survival rates were investigated. Results—Median survival time was 653 days (range, 2 to 4,580 days). Prolonged anesthesia (median, 300 minutes; range, 225 to 445 minutes) reduced overall survival rate but did not influence short-term survival rate. No associations were identified between survival rates and anesthetic agent used, amount and type of fluid administered IV, physiologic abnormalities, and blood product administration. All cats that received μ-opioid receptor antagonists at anesthetic recovery to reverse the effects of μ-opioid receptor agonists survived for at least 30 days. High Hct at the end of anesthesia was also associated with an increase in short-term survival rate. Two cats had an intraoperative hemoglobin oxygen saturation < 90%, and both died within 7 days after surgery. Cats > 12 years old had a lower overall survival rate than did younger cats. Conclusions and Clinical Relevance—Minimization of total anesthesia time, reversal of μ-opioid receptor agonists at the end of anesthesia, and prevention of intraoperative decreases in blood oxygen saturation and postoperative decreases in Hct appeared to help maximize postsurgical survival time in cats undergoing RTS.