Admission photoplethysmography-based mortality prediction in hospitalized Ugandan children with suspected or confirmed infection: a feasibility study

Sepsis remains a major cause of preventable pediatric hospital deaths in developing countries, with progress hindered by the lack of effective risk identification tools. Early detection of children at highest risk upon hospital admission is crucial for guiding clinical care and allocating resources, particularly in resource-limited settings. Photoplethysmography, which measures blood oxygen levels, also provides objective insight into cardiovascular alterations associated with sepsis. We conducted a secondary analysis of prospectively collected data from the Smart Discharges project, involving children under five years hospitalized with suspected or confirmed infection at six Ugandan hospitals, and developed models to predict all-cause in-hospital mortality across two age groups (0-6 and 6-60 months). Mortality was 7% in younger and 4.1% in older children. Machine learning models were trained on features extracted from one-minute photoplethysmograms collected at the time of admission. The best-performing model achieved mean values for the area under the receiver operating characteristic curve of 0.70 (95% CI: 0.62-0.76) in the younger cohort and 0.67 (95% CI: 0.56-0.73) in the older cohort, with corresponding values for the area under the precision-recall curve of 0.18 (95% CI: 0.12-0.27) and 0.14 (95% CI: 0.06-0.22), respectively. Calibration within risk strata was satisfactory (Brier scores 0.06 and 0.04), and decision curve analysis showed clinical utility. Notably, the models predictive capacity, although moderate, was achieved with a rapid and readily available objective measurement at admission, without the need for extended monitoring. While less accurate than most existing risk scores and not a substitute for clinical judgment, these simple admission-based models may help identify high-risk children and guide targeted interventions where sophisticated diagnostics are unavailable. External validation is needed before adoption. Author summarySepsis poses a serious risk to children in hospitals with limited resources, and it can be difficult for healthcare workers to recognize which patients are in the most danger quickly. In our study, we investigated whether a simple fingertip sensor, commonly used in hospitals to measure oxygen levels, could help identify high-risk children upon arrival. We utilized data from Ugandan hospitals to develop computer-based tools that analyze signals from these sensors and support care decisions, eliminating the need for advanced equipment or laboratory tests. While our approach did not match the accuracy of the most advanced methods, it provided valuable information from a single, quick measurement at admission. These findings suggest that simple and accessible tools can still help staff make better decisions and prioritize children who require urgent care, even in settings with limited resources. We hope further work will refine these techniques and test their value in other hospitals and regions.