The Relationship Between Heart Rate and Body Temperature in Critically Ill Patients

OBJECTIVE: The presence of tachycardia in critically ill patients is frequently used as an indication of severity of illness and to guide treatment decisions but can be influenced by body temperature, thus confounding its interpretation. There are few data available on the relationship between body temperature and heart rate in critically ill patients. DESIGN: Retrospective analysis of prospectively collected data. SETTING: Mixed medical-surgical university hospital ICU. PATIENTS: All patients admitted to the ICU between November 2006 and August 2019. MEASUREMENTS AND MAIN RESULTS: Body temperature was recorded in the electronic medical records at least hourly, from invasive measurements (esophageal probe, indwelling urinary catheter, pulse contour cardiac output monitoring system, or pulmonary artery catheter) or manual tympanic recordings. Heart rate was monitored continuously and hourly values were recorded in the electronic medical record. Change in heart rate with change in body t...