Prognostic Nutritional Index as a Severity Indicator in Mechanically Ventilated Children

Introduction: Critically ill patients encounter significant health problems, which are reflected in the morbidity and mortality rates in intensive care units (ICUs). The prognostic nutritional index (PNI), which gauges immunological and nutritional health, is increasingly recognized as a significant predictor of outcomes in critical care units. The present study aimed to assess the prognostic nutritional index as a marker of severity in mechanically ventilated children. Methods: This retrospective cross-sectional study was conducted from January 2023 to October 2024 in the Paediatric Intensive Care Unit (PICU) of M S Ramaiah Medical College Hospital, Bangalore. All critically ill children admitted to the PICU during the study period were included. Purposive sampling was used; 184 consecutive critically ill children (93 were mechanically ventilated and 91 were non-mechanically ventilated) were included. Retrospective case record data collection was performed using a demographic questionnaire, including Paediatric Risk of Mortality III (PRISM-3) scoring and complete blood counts. The data were analysed using SPSS 22 software. Statistical analysis, including Pearson correlation, was used to evaluate the association between the prognostic nutritional index and the severity of illness. P-values < 0.05 were considered significant. Results: The mean PNI for ventilated patients was 47.01, which was significantly lower than that for non-ventilated patients (56.84; P = 0.002). PNI also showed a weak positive correlation with length of hospital stay (r = 0.03282, P = 0.7548) and PRISM-3 score (r = 0.105). The mean PNI was lower among non-survivors than among survivors (48.35 vs. 52.73), but the difference was not statistically significant (P = 0.298). Conclusion: Our findings highlight that, at admission, PNI is a weak severity indicator among mechanically ventilated children.