A study to compare two different modes of pain relief techniques (continuous delivery of Lidocaine (a pain killer) through the vein and epidural infusion(delivery of pain killer around the layers of spinal cord) in all patients undergoing keyhole surgery for colon cancer

Intervention1: Lidocaine: Administered intravenously as 2mg/kg bolus followed by infusion at 2mg/kg/hr from the start of surgery till 30 minutes after surgery
Control Intervention1: Thoracic Epidural Analgesia: Thoracic Epidural Catheter is inserted at T8-T9 level through which 0.25% Bupivacaine with 1mcg/cc Fentanyl is administered as an infusion for 48 hours post operatively
Primary outcome(s): Postoperative pain score at various intervals using Visual Analogue Score(VAS)Timepoint: 2,4,8,12,24 hours post operative