Keibun Liu, MD. PhD
Postdoctoral Research Fellow
The Prince Charles Hospital, Critical Care Research Group, Japan
Disclosure information not submitted.
Daizoh Saitoh
MD, PhD
National Defense Medical College, United States
Disclosure information not submitted.
Title: Factors differentiating sepsis from heatstroke in patients with suspected heatstroke
Introduction: Sepsis is difficult to distinguish from heatstroke at the initial assessment, since symptoms and severity of multi-organ failure (MOF) often overlap in these two conditions. While these conditions require different therapeutic strategies, little is known about the differences in their characteristics at the initial assessment. Therefore, we aimed to identify sepsis-related factors among patients who were admitted with suspected heatstroke.
Methods: This is a multicenter, retrospective cohort study of four tertiary emergency centers in Japan between 2016 and 2020. We retrospectively grouped patients with the admission diagnosis of heatstroke or suspected heatstroke based on whether they met the diagnostic criteria for sepsis, by applying the Sepsis-3 criteria at admission. We used a lasso regression to identify factors related to meeting the criteria for sepsis. The candidate factors included patient demographics, vital signs, past medical history, and laboratory data. Subsequently, we fitted a multivariable logistic regression model to determine the association of the identified factors with sepsis.
Results: A total of 104 patients were identified. The median age of patients was 76 years and 70% were male. Of these, 25 (24%) patients met the criteria for sepsis. The median qSOFA score at hospital arrival was not statistically different (2 for both groups), but the median SOFA score was higher in the sepsis group (7 vs 4, p< 0.001). In-hospital mortality was similar between two groups (8.0% vs 7.6%), although the percentage of patients directly discharged home was significantly lower in the sepsis group (28.0% vs 55.7%, p=0.02). The regression model showed that the SOFA score (OR 1.40, 95% CI 1.15–1.70), platelet count (OR 0.91 per 1000/μl increase, 95% CI 0.83–0.99), serum bilirubin (OR 0.41 per 1 mg/dL increase, 95% CI 0.2–0.82), and serum C-reactive protein (CRP) (OR 1.16 per 1mg/dL increase, 95% CI 1.04–1.29) were independently associated with sepsis.
Conclusion: One of four patients with the admission diagnosis of heatstroke or suspected heatstroke met the diagnostic criteria for sepsis and had poor clinical outcomes. MOF, especially coagulation dysfunction, was associated with sepsis among cases suspected of heatstroke. Lower serum bilirubin and higher serum CRP were also associated with sepsis.