Preinduction Epidural catheter will be placed and Standard General Anaesthesia with Volume Controlled Ventilation (Tidal Volume 8ml/Kilogram ) and Positive End Expiratory Pressure 5 centimeters of water for all patients. Postinduction Radial artery cannulation and Ultrasound guided Internal Jugular cannulation will be performed for all patients .Maintenance Fluid crystalloids 2ml/kg will be given to both the Groups. In Stroke Volume Variation SVV Group Flotrac Transducer (MHD8 model Edwards Lifesciences LLC, Irvine,CA 92614,USA) will be attached to radial artery cannula to obtain SVV values and for values < 11 colloid bolus 200ml will be given over 10 minutes and postbolus values noted. In Plethysmography Variability Index PVI Group pulse Oximeter will be placed on index finger and covered to avoid ambient light will be attached to Masimo Radical 97 Monitor to measure continuous Perfusion Index and Plethysmography Variability Index for values <11 colloid bolus 200ml will be given over 10 minutes and change in PVI value noted. Intraoperative heart rate , Mean arterial Pressure , Oxygen Saturation, End tidal carbon dioxide, Central venous pressure , Urine output will be measured in all patients.With optimal fluids if Mean Arterial Pressure is below 70 mmHg than titrating dosage Norepinephrine infusion will be commenced.At the end of surgery reversal agents will be administered and trachea extubated , note will be made of any patient requiring postoperative ventilator support.Arterial blood gas analysis will be performed at beginning and end of surgery and at postoperative 24 and 48 hours to measure serum lactate levels . Patient will be monitored in Postanaesthesia Care Unit for any Cardiac , Respiratory event , Serum Creatinine levels will be measures at 24 and 48 hours , Appearance of bowel sounds will be noted , Length of ICU stay will be recorded for all patients.
Patients were allotted to two Groups , SVV Guided Fluid Therapy Group received intraoperative fluids to maintain SVV <11 , and PVI Guided Group received intraoperative Fluids to maintain PVI<11