Admission body temperature and in-hospital mortality in critically ill children with pneumonia: a retrospective cohort study

Objective : To evaluate whether admission body temperature (BT) is associated with in-hospital mortality in critically ill children with pneumonia. Design : Retrospective cohort study. Methods : This study employed a retrospective cohort design using records derived from the Pediatric Intensive Care (PIC) database collected between 2010 and 2018. Children aged > 28 days and < 18 years who were admitted to the PICU with a diagnosis of pneumonia were included in the analysis. Based on BT measured at admission, patients were grouped as hypothermic (< 36.5℃), normothermic (36.5–37.4℃), or hyperthermic (≥ 37.5℃), with additional classification according to the degree of hyperthermia. The association between admission BT and in-hospital mortality was evaluated using multivariable logistic regression. Furthermore, restricted cubic spline modeling, along with subgroup and sensitivity analyses, was undertaken to test the consistency of the findings. Results : In total, 394 pediatric patients with severe pneumonia were retained for analysis. Admission BT was independently linked to in-hospital mortality, with higher values corresponding to an increased risk of death. When compared with patients presenting with normal BT, those with hyperthermia exhibited a substantially greater likelihood of mortality (OR 3.10, 95% CI 1.26–7.62), and this risk was even more pronounced among individuals with severe hyperthermia (OR 5.74, 95% CI 1.55–21.20). Hypothermia, however, showed no statistically significant association with mortality. Analysis using restricted cubic splines supported a linear pattern between BT and mortality risk. Subgroup analyses revealed no significant effect modification by age, gender, or SpO2. Conclusions : Among critically ill children with pneumonia, elevated admission BT—particularly severe hyperthermia—was associated with increased in-hospital mortality. Admission BT may be a readily accessible and clinically informative parameter for early risk stratification in the PICU. Clinical trial number: Not applicable.