Comparative evaluation of intraperitoneal bupivacaine and bupivacaine ketamine combined with lung recruitment for reducing postoperative shoulder pain in laparoscopic cholecystectomy

Background
Shoulder pain (SP) was first reported after laparoscopic gynecological procedures. It is assumed to be multifactorial in nature. Several methods to reduce SP after laparoscopic cholecystectomy (LC) have been postulated. In this study, we have worked to decrease it using 2 approaches; lung recruitment maneuver and intraperitoneal local analgesic instillation.
Objectives
This study was designed to assess the clinical efficacy of ketamine as an adjunct to intraperitoneal bupivacaine for the relief of post-operative shoulder pain after LC.
Methods and material
This prospective, randomized, double-blinded study is comprised of 40 patients of either sex, with age range of 20–50 years, planned for elective LC. Just after inflating the pneumoperitoneum, the surgeon sprayed 50 mL of a blinded solution intraperitoneally. Patients were randomly allocated to: group B received a 50 mL solution of intraperitoneal bupivacaine 0.25% and group BK received 0.5 mg/kg ketamine mixed with bupivacaine 0.25%.
Results
This study showed that ketamine bupivacaine admixture had made dramatic decline in shoulder pain VAS scores specifically at the 24th hour; 15 patients in the BK group had either VAS score zero or 1 when compared to B group whom their lowest score at the 24th hour was 4. Also, there was more decrease in postoperative analgesic consumption in BK group. No psychomimetic side effects or sedation were noticed in both groups.
Conclusions
We conclude that intraperitoneal instillation of low dose ketamine to bupivacaine 0.25% in elective LC significantly reduced post-operative shoulder pain and analgesic requirement when compared to bupivacaine 0.25% alone.