Comparison between intraperitoneal instillation of plain versus carbonated bupivacaine after laparoscopic cholecystectomy

Background: Laparoscopic surgeries are becoming more acceptable and many methods are being tried to reduce postoperative pain.
Material and Method: 200 patients divided into: group 1 (BP) patients received 0.5 % plain Bupivacaine and Group2 (BC) patients received Carbonated 0.5% Bupivacaine. Local anesthetic solution was instilled intraperitoneally through infra-umbilical incision before removal of trocar at the end of surgery. Degree of post operative pain was assessed using VAS in case of spontaneous pain and VRS on arrival inrecovery room, immediately after surgery and thereafter 1 hourly till 12 hours postoperatively. Patients having VAS >4 after surgery were administered a bolus of Diclofenac (75 mg) i.v. as rescue analgesic.
Results: VAS scores immediately postoperatively were 4.08±0.78 in BP and 3.54±0.78 in BC [p<0.05]. No significant difference in VAS scores from 1hour to 10th hour postoperatively. VAS score at 11th hour were 2.42±0.74 in BP and 2.20±0.51 in BC [p<0.05] but no significant difference at 12th hour. Immediate post operative rescue analgesic requirement, was significantly more in BP than in BC patients [p<0.05]. From 1st hour to 5th hour analgesic requirement rate was found almost same in both the groups. At 6th hour rescue analgesic requirement was significantly more in BP than in BC [p<0.05]. There was no significant difference found in analgesic requirement rate from 7th hour to 12th hour in both the groups.
Conclusion: We concluded that Intraperitoneal instillation of carbonated bupivacaine is superior to plain bupivacaine for the relief of post operative pain in patients undergoing laparoscopic surgery.