Evaluation of the non-invasive Temple Touch Pro temperature monitoring system compared with oesophageal temperature in paediatric anaesthesia (PETER PAN): A prospective observational study.

BACKGROUND: Monitoring peri-operative body temperature in children is currently mainly achieved through invasive devices. The Temple Touch Pro Temperature Monitoring System estimates core temperature noninvasively based on heat flux thermometry. OBJECTIVE: To investigate the agreement of this noninvasive sensor against standard oesophageal core temperature. DESIGN: A prospective observational study. SETTING: University hospital recruiting between April and July 2021. PATIENTS: One hundred children (32 girls) aged 6 years or younger scheduled for noncardiac surgery, resulting in 6766 data pairs. Exclusion criteria were contraindication for the insertion of an oesophageal temperature probe, and procedures in which one of the measurement methods would interfere with the surgical field. MAIN OUTCOME MEASURES: Primary outcome was the agreement analysis by a Bland-Altman comparison with multiple measurements. Posthoc, we performed another agreement analysis after exclusion of a statistically determined equilibration time. Secondary outcomes were the temperature differences over time and subgroup analysis of hypothermic, normothermic and hyperthermic temperature ranges, age, sex and sensor's side by type III analysis of variance. Further, we correlated the sonographically determined depth of the artery with trueness. RESULTS: The mean difference was -0.07°C (95% CI -0.15 to +0.05) with limits of agreement of -1.00 and +0.85°C. After adjusting for an equilibration time of 13 min, the mean difference improved to -0.04°C (95% CI -0.08 to +0.01) with limits of agreement of -0.68 and +0.60°C. Concordance correlation coefficient was 0.83 (95% CI 0.82 to 0.84). Differences between the skin sensor and oesophageal reference increased over time by -0.05°C per hour. Subgroup analysis showed no clinically relevant differences. Depth of artery negatively correlated with trueness by 0.03°C per millimetre. CONCLUSIONS: Although the Temple Touch Pro sensor showed acceptable accuracy after allowing for an equilibration time, it still needs further investigation for routine use in children. This particularly affects accuracy in hypothermic ranges, imprecise positioning and applicability in children with immature or vulnerable skin. TRIAL REGISTRATION: German Clinical Trials Register, identifier: DRKS00024703.

Evaluation of the Temple Touch Pro™ noninvasive core-temperature monitoring system in 100 adults under general anesthesia: a prospective comparison with esophageal temperature.

Perioperative hypothermia is still common and has relevant complication for the patient. An effective perioperative thermal management requires essentially an accurate method to measure core temperature. So far, only one study has investigated the new Temple Touch Pro™ (Medisim Ltd., Beit-Shemesh, Israel). during anesthesia Therefore, we assessed the agreement between the Temple Touch Pro™ thermometer (TTP) and distal esophageal temperature (TEso) in a second study. After approval by the local ethics committee we studied 100 adult patients undergoing surgery with general anesthesia. Before induction of anesthesia the TTP sensor unit was attached to the skin above the temporal artery. After induction of anesthesia an esophageal temperature probe was placed in the distal esophagus. Recordings started 10 min after placement of the esophageal temperature probe to allow adequate warming of the probes. Pairs of temperature values were documented in five-minute intervals until emergence of anesthesia. Accuracy of the two methods was assessed by Bland-Altman comparisons of differences with multiple measurements. Core temperatures obtained with the TTP in adults showed a mean bias of -0.04 °C with 95% limits of agreement within - 0.99 °C to + 0.91 °C compared to an esophageal temperature probe. We consider the TTP as a reasonable tool for perioperative temperature monitoring. It is not accurate enough to be used as a reference method in scientific studies, but may be a useful tool especially for conscious patients undergoing neuraxial anesthesia or regional anesthesia with sedation. Trial registration This study was registered in the German Clinical Trials Register (DRKS-ID: 00024050), day of registration 12/01/2021.

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

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 .