Hypothermia significantly improves the rate of recovery of function following abdominal surgery—particularly radical prostatectomy. Prior to commencing surgery the tissues at and surrounding the site of the surgery are cooled by means of an endorectal cooling balloon inserted into the patient's rectum. The uninflated balloon is inserted and then inflated with cooling fluid which fluid is constantly circulated in and out to lower the temperature. Improved hypothermia can be achieved by bathing internal tissue with chilled water or buffer. Limitation of surgically induced damage can be demonstrated by the more rapid regain of continence in radical prostatectomy patients treated with hypothermia during surgery.