Impact of heart rate on the outcome of hypothermic patients.

Objective: This study aimed to identify prognostic factors for hypothermia, including hormone levels.

Materials and methods: This retrospective analysis used data from our department's database from November 2018 to December 2023. Inclusion criteria comprised cases with a prehospital diagnosis of hypothermia (body temperature <35°C) established by emergency medical technicians. Patients in cardiac arrest upon arrival were excluded from the study. This study investigated various parameters, including age, sex, body temperature, systolic blood pressure, heart rate, Glasgow Coma Scale (GCS) score, and adrenocorticotropic hormone (ACTH), cortisol, thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4), C-reactive protein, total protein, albumin levels, and outcomes. Patients were categorized into two groups based on the discharge outcome: fatal and survival groups. This study compared the variables between the two groups.

Results: There were 28 and 53 patients in the fatal and survival groups, respectively. The average heart rate and FT3 levels in the fatal group were significantly lower than those in the survival group. The average cortisol and CRP levels in the fatal group were significantly higher than those in the survival group.

Conclusion: This is the first report to demonstrate that hypothermic patients with a fatal outcome tend to have low heart rate, low FT3 levels, high cortisol levels, and inflammation upon arrival at the hospital. Further studies with larger sample sizes are needed to confirm the clinical significance of our findings.