Mind the Gap! Core-Peripheral Temperature Gradient and Its Relationship to Mortality in Major Burns

The association between hypothermia and poor outcomes in severe burn injury is well established. However, the significance of the core-peripheral temperature gradient has not previously been investigated. Institutional guidance at our burns centre advocates avoiding hypothermia and targeting body temperature between 37.5-39.5° C. Core-peripheral temperature gap should be ≤2°C, with this being based on expert opinion. Data from 61 patients admitted to the Intensive Care Unit (ICU) with severe burns between 2016 and 2022 were analysed. A higher core temperature at 48 hours, avoidance of hypothermia and a core-peripheral temperature gap >2°C were associated with reduced odds of mortality. The mean core body temperature and core-peripheral temperature gap increased over the first 48 hours (r=0.5, p<0.001). All non-survivors had a core-peripheral gap <2°C at 48 hours. Survivors had a higher mean 48-hour gap (1.6 [95%CI:1.3-1.9]) vs non-survivors (0.8 [95%CI:0.2-1.4; p=0.04]). Our findings support previous studies suggesting that avoiding hypothermia and achieving a higher target temperature are associated with reduced mortality. However, it challenges previous expert consensus that a lower core-peripheral gap indicates better outcomes. Further research with a larger cohort of patients is required to identify whether a higher core-peripheral temperature gap predicts patient outcomes in critically ill patients with severe burns.