COMPARISON OF ESOPHAGEAL, TYMPANIC, AND FOREHEAD SKIN TEMPERATURES INADULT PATIENTS

Study Objective: To compare esophageal, tympanic membrane, and forehea d skin temperatures in patients undergoing elective surgeries. Design: Prospective clinical study. Setting: Operating room and postanesthesi a care unit of a tertiary care teaching hospital. Patients: 40 adult A SA status I, II and III patients requiring anesthesia and surgery. Int ervention: Application of crystalline thermometry strips to the forehe ad of patients. Measurements and Main Results: Concurrent forehead ski n, tympanic membrane, and lower esophageal and skin temperatures was 0 .3 degrees C, between tympanic membrane and skin was 0.5 degrees C, an d between esophageal and tympanic membrane was -0.1 degrees C. The lim its of agreement (precision) between esophageal and skin temperatures were: -1.64 degrees C to +2.32 degrees C, between esophageal and tympa nic membrane were: -1.02 degrees C to +0.74 degrees C, and between tym panic membrane and skin were: -1.48 degrees C to +2.52 degrees C. Ther e was no significant relation between the change in skin temperature a nd change in esophageal temperature, whereas there was a weak linear r elation between change in skin temperature and change in tympanic memb rane temperature (y = -0.03 + 0.09, r = 0.12). Conclusion: There was a lack of precision between the clinically accepted measurements (lower esophageal and tympanic membrane) and the skin temperature measuremen t. The data suggest that forehead skin temperature is not interchangea ble with standard core temperture measurements, and that sole reliance on the forehead skin measurement in the perioperative setting could a dversely affect patient care.