Intraoperative Cerebral and Somatic Oxygen Saturation Monitoring as Predictors of Postoperative Complications in Liver transplantation : An observational study

Patients undergoing Liver transplant surgery will be taken in operating room. Standard monitors will be attached. NIRS electrode will be applied to  over forehead and same side forearm and thigh. Baseline values will be recorded after signal stabilization. General Anaesthesia will be given as per institutional protocol. Cerebral and somatic NIRS data will be collected every 10 mins starting from start of surgery to the end of surgery. NIRS values at all the events of surgery will be noted- after induction, after dissection phase, anhepatic phase (at the time of IVC clamping), reperfusion phase, 1 hour after reperfusion phase. A 20% fall in saturation values will be considered as significant hypoperfusion. Correction will be given to maintain MAP >70mmHg, Hb >7gm/dl and PaO2

100mmHg. The intraoperative monitoring will include operation time, requirement for a norepinephrine infusion, averages of the hemodynamic parameters (systolic and diastolic blood pressure, heart rate, and central venous pressure), blood loss, blood product requirements (packed red blood cells, fresh frozen plasma, single donor platelets, and cryoprecipitate transfusions), laboratory data (hemoglobin and lactate), hourly urine output. Postoperatively, Cystatin C and Urine NGAL will be sent at 48 hours, Sr. Creatinine levels will be sent for 7 days, Renal resistive index and Confusion assessment method CAM-ICU will be seen for 7 days. Post-operative respiratory insufficiency will be seen in the form of postextubation hypoxemia, reintubation, acute respiratory failure, pulmonary edema, pneumonia, and atelectasis. Cardiovascular complications will be seen in the form of- arrhythmia, heart failure, myocardial infarction, cardiac arrest, thromboembolism, and/or stroke.