Exacerbation of circadian rhythms of core body temperature and sepsis in trauma patients.

Purpose: This study aimed to describe by mathematical modeling an accurate course of core body temperature (CBT) in severe trauma patients and its relation to sepsis.

Methods: In a cohort of severe trauma, the CBT measurements were collected for 24 h on day 2 after admission and rhythmicity assessed by Fourier transform and Cosinor analysis to describe circadian features (frequency and amplitude). CBT was compared between patients who developed sepsis or not during the early ICU stay.

Results: 33 patients were included in this analysis. 24 patients (73%) had a predominant rhythm of 24 h (period). The main period was lower in the 9 remaining patients (6 of 12 h, 1 of 8 h, and 2 of 6 h). Other significant frequencies of oscillation (second and third frequencies) were found, which showed an association of several well-marked rhythms. Patients with sepsis (n = 12) had a significantly higher level of CBT, but also more intense rhythms and higher amplitudes of CBT.

Conclusion: Trauma patients exhibit complex temperature circadian rhythms. Early exacerbation of the temperature rhythmicity (in frequency and amplitude) is associated with the development of sepsis. This observation accentuates the concept of circadian disruption and sepsis in ICU patients.