Comparison of core temperature monitoring methods during cytoreductive surgery with hyperthermic intraperitoneal chemotherapy: a prospective observational study.

Background: During cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (HIPEC), precise core temperature monitoring is critical for patient safety. This prospective study evaluated the agreement among three core temperature monitoring modalities: nasopharyngeal temperature (Tnaso), zero-heat flux cutaneous thermometer (TSpotOn), and oesophageal temperature (Teso).

Methods: Temperatures were measured simultaneously; agreement between monitoring sites was assessed using Bland-Altman analysis for repeated measures including mean bias, 95% limits of agreement, and confidence intervals, alongside Lin's concordance correlation coefficient (LCCC). The proportion of paired differences within the clinically acceptable limit of 0.5 °C was reported.

Results: The mean difference between Tnaso and TSpotOn was -0.04 ± 0.33 °C (95% limits: -0.69 to 0.62), and between Tnaso and Teso was 0.02 ± 0.35 °C (95% limits: -0.66 to 0.71), with LCCC for both comparisons at 0.94 (95% CI: 0.93-0.94), indicating substantial agreement. However, up to 14% of Teso pairs exceeded the 0.5 °C threshold, suggesting potential clinical relevance. Notable rapid temperature decline and subsequent rebound were observed post-HIPEC at Tnaso and TSpotOn sites.

Conclusion: All three monitoring methods correlated strongly overall, but Teso exhibited phase-dependent discrepancies, particularly after HIPEC. These findings support tailoring core temperature measurement site selection with attention to the target organ, especially in laparotomy-based HIPEC procedures.

Trial registration: The study was registered in the clinical trials registry cris.nih.go.kr (Registration Number: KCT0003980).