Objective: To assess the lactate and base excess values taken on admission and after 24 hours can be used as a prognostic marker of patient outcome. Patients and methods: A retrospective cohort study was conducted in Indiana Hospital and Heart Institute, emergency unit. Total 60 consecutive patients were treated in 16 bedded emergency units. Arterial blood samples were collected on admission and 24 hours of admission. Results: Lactate level of 1.5 mmol/l or more were having 89.5% sensitivity and 75% specificity for prediction of in-hospital death, with a greater possibility of ventilator support and need of inotropes with multi-organ dysfunction syndrome (p<0.000). Conclusions: Prognostic value of lactate can vary considerably depending on the patient population; lactate generally increases the ability to predict non-survival, prognosis and patient outcome. Base excess and lactate are still indicators of severity of disease and can be used to monitor treatment and response.