Blood Lactate Levels and PRISM III Scores for Prognosis of Shock during Paediatric Emergencies: A Prospective Observational Cross-sectional Study

Introduction: The appropriate management of shock in paediatrics includes early recognition of tissue hypoxia and its timely intervention thus preventing shift to anaerobic metabolism, metabolic acidosis and cell death.

Aim: To determine the effectiveness of blood lactate levels as a prognostic indicator of mortality in children with shock admitted to Paediatric Intensive Care Unit (PICU) and to correlate between blood lactate levels and Paediatric Risk of Mortality III (PRISM III) scores.

Materials and Methods: This was a prospective observational cross-sectional study conducted between January 2018 to May 2019 in the PICU of a tertiary care centre in rural India. A total of 144 children presenting with shock to PICU were included in the study. The serum lactate values were assessed at 0, 12 and 24 hours of admission. The various parameters of PRISM III scores was documented for each child at 0, 12 and 24 hours of admission and score was calculated. Lactate levels and PRISM III score were analysed using the Receiver Operating Characteristic (ROC) curve and optimal cut-off points were chosen for the calculation of sensitivity, specificity, positive and negative predictive values. An area under the ROC curve above 0.8 indicated fairly good prediction.

Results: The most common aetiologies for shock in the present study included severe sepsis (42.3%), acute gastroenteritis (21.5%) and dengue fever (21.5%). Persistent hyperlactatemia was observed in non survivors and serum lactate values persistently greater than 4 mmol/L within the first 24 hours of admission were associated with greater risk of mortality. The area under the ROC curve for the serum lactate levels (0.958) suggested that, it was a strong predictor of mortality in study subjects when compared to PRISM III score which had area under the ROC curve 0.866.

Conclusion: Serum lactate values are an early useful predictor of mortality in children with shock and it is more feasible indicator when compared to PRISM III scores.