Urinary bladder temperature monitoring: a new index of body core temperature.

A new method of core body temperature monitoring is introduced and compared to currently used methods. A close correlation exists between urinary bladder temperatures and each of the techniques studied. The correlation is good when compared to esophageal and rectal temperature and best when compared to pulmonary arterial blood temperature. During rapid rewarming after extracorporeal circulation, the urine temperature consistently increases faster than rectal or esophageal and seemingly is a better measure of blood temperature rather than muscle mass temperature. Urine temperature monitoring is reliable, safe, convenient, and accurate for routine intraoperative and postoperative continuous use in adult patients with urethral catheterization.