The effect of burn mechanism on pediatric mortality in Malawi: A propensity weighted analysis

The burden of global trauma disproportionately affects low- and middle-income countries, with a high incidence in children. Thermal injury represents one of the most severe forms of trauma and is associated with remarkable morbidity and mortality. The predictors of burn mortality have been well described (age, % total body surface area burn [TBSA], and presence of inhalation injury). However, the contribution of the burn mechanism as a predictor of burn mortality is not well delineated.

This is a retrospective analysis of prospectively collected data, utilizing the Kamuzu Central Hospital (KCH) Burn Surveillance Registry from May 2011 to August 2019. Pediatric patients (≤12 years) with flame and scald burns were included in the study. Basic demographic variables including sex, age, time to presentation, %TBSA, surgical intervention, burn mechanism, and in-hospital mortality outcome was collected. Bivariate analysis comparing demographic, burn characteristics, surgical intervention, and patient outcomes were performed. Standardized estimates were adjusted using inverse-probability of treatment weights (IPTW) to account for confounding. Following weighting, logistic regression modeling was performed to determine the odds of in-hospital mortality based on burn mechanism.

During the study period, 2364 patients presented to KCH for burns and included in the database with 1794 (75.9%) pediatric patients. Of these, 488 (27.6%) and 1280 (72.4%) were injured by flame and scald burns, respectively. Males were 47.2% (n = 230) and 59.2% (n = 755) of the flame and scald burn cohorts, respectively (p < 0.001.) Patients presenting with flame burns compared to scald burns were older (4. 7 ± 3.1 vs. 2.7 ± 2.3 years, p < 0.001) with greater %TBSA burns (17.8 [IQR 10-28] vs 12 [IQR 7-20], p < 0.001). Surgery was performed for 42.2% (n = 206) and 19.9% (n = 140) of the flame and scald burn cohorts, respectively (p < 0.001.) Flame burns had a 2.6x greater odds of in-hospital mortality compared to scald burns (p < 0.001) after controlling for sex, %TBSA, age, time to presentation, and surgical status.

In this propensity-weighted analysis, we show that burn mechanism, specifically flame burns, resulted in a nearly 3-fold increase in odds of in-hospital mortality compared to scald burns. Our results emphasize flame and scald burns have major differences in the inflammatory response, metabolic profile over time, and outcomes. We may further utilize these differences to develop specialized treatments for each burn mechanism to potentially prevent metabolic dysfunction and improve clinical outcomes.