Postoperative Analgesia in Laparoscopic Cholecystectomy following Intraperitoneal Magnesium Sulphate: A Prospective Cohort Study

Abstract

Introdution: Postoperative pain and discomfort after laparoscopic cholecystectomy is partly because of distension, tearing, separation of parietal peritoneum and surgical manipulation. Intraperitoneal administration of Magnesium Sulphate (MgSO4 ) is thought to desensitise the after effects of pneumoperitoneum in addition to providing analgesia. Aim: To analyse the effect of intraperitoneal magnesium sulphate on postoperative analgesia and occurrence of shoulder pain after laparoscopic cholecystectomy. Materials and Methods: The present study was a prospective cohort study which was conducted at the Government Medical College, Kozhikode, Kerala, India, from February 2019 to December 2020, included 60 adult patients scheduled for elective laparoscopic cholecystectomy under general anaesthesia were selected and they were divided into two groups, group M and group N. Patients in group M received 30 mg/kg MgSO4 which was instilled into the gallbladder bed intraperitoneally by the surgeon after resection of gallbladder and patients who did not receive MgSO4 were included in group N. Postoperative pain was assessed using Visual Analog Scale (VAS) and VAS score> 3 was managed with Intravenous (IV) paracetamol 15 mg/kg. If pain was not relieved by this, IV tramadol 50 mg was supplemented. Time to first rescue analgesic, the total analgesic requirement and the incidence of shoulder pain in 24 hours were noted. Haemodynamics, recovery profile, incidence of Postoperative Nausea and Vomiting (PONV), any adverse events were also noted and analysed. Results: Mean pain scores (VAS) were significantly lower in group M and time to first analgesic requirement was longer in group M (4.23±2.31 hours) compared with group N (1.07±0.67 hours), PONV was significantly higher in group N. Sedation scores were significantly high in group M and there were no significant differences in haemodynamic and recovery profile and incidence of shoulder pain in both the groups. Conclusion: Intraperitoneal instillation of MgSO4 provides effective postoperative analgesia and reduces nausea and vomiting in patients undergoing laparoscopic cholecystectomy without any significant side-effects.