Accuracy of zero-heat-flux thermometry and bladder temperature measurement in critically ill patients

Abstract

Core temperature (TCore) monitoring is essential in intensive care medicine. Bladder temperature is the standard of care in many institutions, but not possible in all patients. We therefore compared core temperature measured with a zero-heat flux thermometer (TZHF) and with a bladder catheter (TBladder) against blood temperature (TBlood) as a gold standard in 50 critically ill patients in a prospective, observational study. Every 30 min TBlood, TBladder and TZHF were documented simultaneously. Bland–Altman statistics were used for interpretation. 7018 pairs of measurements for the comparison of TBlood with TZHF and 7265 pairs of measurements for the comparison of TBlood with TBladder could be used. TBladder represented TBlood more accurate than TZHF. In the Bland Altman analyses the bias was smaller (0.05 °C vs. − 0.12 °C) and limits of agreement were narrower (0.64 °C to − 0.54 °C vs. 0.51 °C to – 0.76 °C), but not in clinically meaningful amounts. In conclusion the results for zero-heat-flux and bladder temperatures were virtually identical within about a tenth of a degree, although TZHF tended to underestimate TBlood. Therefore, either is suitable for clinical use.German Clinical Trials Register, DRKS00015482, Registered on 20th September 2018, http://apps.who.int/trialsearch/Trial2.aspx?TrialID=DRKS00015482.

Non-Invasive Monitoring of Core Body Temperature for Targeted Temperature Management in Post-Cardiac Arrest Care

“…In contrast, the SpotOn™ monitor is non-invasive and easy to apply. The only potential drawbacks of the SpotOn™ device include restrictions with application in patients with adhesive allergies and potential for skin breakdown with extensive use, although these adverse events were seen neither in our study nor in a prior study that used SpotOn™ for the duration of time that was similar to TTM protocols ( 13 ).…”

“…The SpotOn™ thermometer has acceptable accuracy and precision for continuous core body temperature monitoring in perioperative settings ( 8 – 10 ) and during TTM ( 12 , 13 ). Our work compliments these studies by providing a larger dataset spanning broader temperature ranges during TTM ( 13 ). Although they have become standard of care, invasive temperature monitors still have associated risks.…”

Non-invasive Monitoring of Core Body Temperature for Targeted Temperature Management in Post-Cardiac Arrest Care

“…In these cases, indirect monitoring of brain temperature using SpotOn™ would be highly relevant. The only potential drawbacks of the SpotOn™ device include restrictions with application in patients with adhesive allergies and potential for skin breakdown with extensive use, although these adverse events were not seen in our study, nor in a prior study that used SpotOn™ for the duration of time similar to TTM protocols (13).…”

A Novel Non-Invasive Thermometer for Continuous Core Body Temperature: Comparison with Tympanic Temperature in an Acute Stroke Clinical Setting

“…Usually, an active sensing device consists of an insulator patch covered by an electric heater, which creates an isothermal tunnel from the body to the skin surface, allowing for the estimation of the temperature of deeper tissues from the skin temperature. These sensors provide clinicians with the ability to non-invasively monitor body temperature, present a good agreement with core body temperature [62] and sufficient accuracy during stable temperature periods [63][64][65], and are increasingly being used to substitute for more invasive core temperature measurements during surgery and in critical care [21,62]. However, the main disadvantage of the zero-heat-flux method is represented by the presence of a servo-controlled heater, necessary for the heat loss to the ambient atmosphere and requiring considerable alternating current power, therefore making it necessary to have it connected to a socket [59].…”