Importance: Early identification of fever or hypothermia is crucial for diagnosing sepsis. Despite their increased use across healthcare systems, concerns have been raised about the accuracy of temporal thermometers among Black patients. Objective: To study the performance of temporal thermometry across race and ethnicity, and its impact on the initiation of the sepsis management bundle (SEP-1). Design: In this retrospective cohort study, records from 2008-2024 in 123 U.S. hospitals were analyzed, including electronic health records from Duke, MIMIC-IV, eICU-CRD-1, and eICU-CRD-2. Patients were included if they had a temporal measurement within one hour of an oral/core measurement (esophageal, bladder, rectal). Main Outcomes and Measures: Hidden Fever was defined when the temporal thermometer read ≤ 38C but oral/core measurement > 38C and Hidden Hypothermia as temporal temperature ≥ 36C but oral/core < 36C. The primary outcome was Hidden Hyper/Hypothermia (HHH) when either Hidden Fever or Hidden Hypothermia happened. Observed Hyper/Hypothermia (OHH) corresponded to an agreement between both measurements, used as a control. To study the impact of temporal thermometry underperformance on SEP-1 bundle initiation, we assessed time to culture ordering, antibiotics administration, and lactate measurement. A composite of these three, whichever happened first, was defined as our secondary outcome. Results: 6,921 paired temperature measurements were studied for the primary outcome analysis, corresponding to 4,248 hospitalizations (2.6% Asian; 12.4% Black; 2.6% Hispanic/Latino; 83.4% White; 44.9% female; 7.7% with HHH) from 115 hospitals. After adjusting for confounders, Black [OR (95% CI): 1.760 (1.219, 2.541), p=0.003] and Hispanic/Latino [OR (95% CI): 2.183 (1.226, 3.888), p=0.008] patients were significantly more likely to present with HHH than White patients. For the study of the secondary outcome, 434 patients had either OHH or HHH. Compared to patients with OHH, patients with HHH had significantly delayed secondary outcomes, with log-rank p-value of 0.002. Conclusions and Relevance: Solely relying on temporal thermometry can lead to missed hyper/hypothermia events, especially among Asian, Black, and Hispanic patients. This has been associated with delays in the initiation of the SEP-1 bundle, which may hamper health systems' compliance with reimbursement programs.

AIW holds equity and management roles in Ataia Medical.

Dr. Wong is supported by the Duke CTSI by the National Center for Advancing Translational Sciences (NCATS) of the National Institutes of Health under UL1TR002553 and REACH Equity under the National Institute on Minority Health and Health Disparities (NIMHD) of the National Institutes of Health under U54MD012530. Dr. Gichoya is a 2022 Robert Wood Johnson Foundation Harold Amos Medical Faculty Development Program and declares support from RSNA Health Disparities grant (#EIHD2204), Lacuna Fund (#67), Gordon and Betty Moore Foundation, NIH (NIBIB) MIDRC grant under contracts 75N92020C00008 and 75N92020C00021, and NHLBI Award Number R01HL167811. Dr. Celi is funded by the National Institute of Health through R01 EB017205, DS-I Africa U54 TW012043-01 and Bridge2AI OT2OD032701, and the National Science Foundation through ITEST #2148451. Dr. Cox is funded by UG3 HL168487 and U01 AT009974.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Four electronic health records (EHR) databases were studied: Duke Health (2014-2024), MIMIC-IV (2008-2022), eICU-CRD-1 (2014-2015), and eICU-CRD-2 (2019-2022). Ethics committee of Duke University gave ethical approval for this work, under Pro00110102. The latter three datasets have been previously de-identified and did not require a waiver for informed consent.

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