https://www.ijnmr.net/back_issues.aspx IJNMR Fatema Huda, Vinod Ingale, Mohammad Haseeb, Imtiyaz Ahmad <b>Introduction:</b> Paediatric shock remains a major cause of morbidity and mortality in intensive care units. Early identification of children at high-risk of adverse outcomes is crucial. Serum lactate and lactate clearance have emerged as potential biomarkers of tissue hypoxia and adequacy of resuscitation, but data in paediatric shock across diverse aetiologies remain limited. <b>Aim:</b> To evaluate the prognostic significance of serial serum lactate levels and lactate clearance at 6, 12, and 24 hours in predicting mortality among children with shock. <b>Materials and Methods:</b> This prospective observational study was conducted over six months (April 2024 to September 2024) in the Paediatric Intensive Care Unit (PICU) of MGM Medical College and Hospital, Aurangabad, Maharashtra, India. Total 100 children aged 1 month to 18 years admitted with clinical shock and an initial serum lactate level &#8805;2 mmol/L were enrolled. Serum lactate levels were measured at admission and at 6, 12, and 24 hours. Lactate clearance was calculated for each interval. The primary outcome was survival status at hospital discharge. Comparisons between survivors and non-survivors were performed using the independent t-test/Mann-Whitney U test and Chi-square/Fisher&#8217;s-exact test as appropriate. ROC analysis was used to assess prognostic performance. <b>Results:</b> A total of 100 children were included; out of them, 72 survived and 28 died (mortality 28%). Non-survivors had significantly higher serum lactate levels at admission and at all subsequent time points (p<0.01). Lactate clearance was significantly lower in non-survivors than survivors at 6, 12, and 24 hours (13.4%, 22.4%, and 26.9% vs. 20.7%, 37.9%, and 55.2%, respectively; p<0.001). Persistently elevated lactate levels and poor lactate clearance were associated with increased mortality. <b>Conclusion:</b> Serial serum lactate measurements and lactate clearance during the first 24 hours of PICU admission are valuable prognostic markers in paediatric shock. Low lactate clearance identifies children at higher risk of mortality and may aid in early risk stratification and monitoring of resuscitation. https://ijnmr.net/article_fulltext.aspx?issn=0973-709x&year=2026&month=July&volume=14&issue=3&page=PO01-PO05&id=2481 https://doi.org/10.7860/IJNMR/2026/88544.2481