Inclusion Criteria:  Patients between the age of 15-60 years with traumatic brain injury, Presenting GCS between 5 to 10, On mechanical ventilation, Either gender.  Exclusion Criteria:  Patient undergoing neurosurgical procedure. Poly trauma. An underlying malignancy. Patients admitted with any medical comorbidity including known case of restrictive or infiltrative lung disease, chronic liver disease, and chronic kidney failure. Patients who expired within 10 days of admission.