Nasal temperature can be used as a reliable surrogate measure of core temperature

Abstract

Background: All current methods of core temperature monitoring have limitations. There is at least one skin temperature probe that can be modified to a nasal temperature probe (NP). This study was conducted to validate this modified skin temperature probe as an accurate surrogate measure of core temperature by comparing the temperature measurements obtained from NP to those from the esophageal stethoscope (ES).

Methods: In 45 adult patients undergoing general anesthesia, one pair of simultaneous temperature measurements were obtained from the ES (E (temp)) and the NP (N (temp)).

Results: The NP was easily inserted in all patients. No patient developed epistaxis. The magnitudes of the differences between N (temp) and E (temp) measurements were 0.2 degrees C or less in 43 out of 45 patients (95.6%); 0.1 degrees C or less in 33 patients (73.3%). On average, the E (temp) was 0.05 degrees C higher than the N (temp). The 95% prediction interval for the E (temp)-N (temp) difference was -0.2 degrees C to +0.3 degrees C. Thus we expect the magnitude of the temperature difference to be less than 1/3 degrees C in the next future individual patient.

Conclusion: In adults, the NP readings closely match the core temperature readings obtained by ES and thus can be used as a reliable surrogate measure of core temperature. This technique may be useful and advantageous in various situations, particularly when other methods of core temperature monitoring are not available or reliable.