Bilateral Infraorbital Nerve Block Versus Intravenous Pentazocine: A Comparative Study on Post-operative Pain Relief Following Cleft Lip Surgery.

Abstract

Infra orbital nerve block is utilized for postoperative pain control in children undergoing cleft lip repair. This study was conducted to compare the effectiveness, advantages and disadvantages of infra orbital nerve block and opioids for postoperative pain relief following cheiloplasty. Sixty paediatric patients aged 3 months - 13 years undergoing cheiloplasty were selected by simple random sampling and were divided into two groups. All the children received standardized premedication with midazolam, were operated upon under general anaesthesia and the block was performed at the end of surgery before reversal. Group B patients were administered bilateral infra orbital nerve block with 0.25% Bupivacaine (upto 2 mg/kg). Group O patients received Pentazocine 0.5 mg / kg IV. Postoperatively, the heart rate and respiratory rates were recorded every 15 minutes for the first 60 minutes, half hourly till 4 hours and then at 12 and 24 hours. Behavioural assessment for pain / discomfort was done at intervals of ½, 1, 2, 3, 4, 12 and 24 hours. Need for supplementary analgesics and duration between the administration of block/opioid and the first dose of supplementary analgesics were noted. Side effects such as nausea and vomiting, pruritus, respiratory depression and bradycardia during each of these periods were noted. Both the groups were comparable for age, sex, weight and operative time with no statistical difference. The mean duration of analgesia for infra orbital nerve block was 357.5 minutes i.e. 5 hours 58 minutes and that for opioid was 231 minutes i.e. 3 hours 51 minutes which was significantly lower than the hours of analgesia provided by the block. Further, at the 4th hour, 76.6% of the patients in Group O required supplementary analgesics, in contrast to only 16.6% in Group B. The incidence of nausea and vomiting and pruritus was also higher in Group O. The results indicate that bilateral infra orbital nerve block provides effective analgesia in the postoperative period, lasting for 6 hours in comparison to 3½ - 4 hours following the administration of intravenous Pentazocine, with no major untoward effects.