THE SAFETY AND EFFICACY Of THE USE OF ACETAZOLAMIDE TO REDUCE REFERRED PAIN IN LAPAROSCOPIC SURGERY

Background: Acetazolamide is a carbonic anhydrase inhibitor. It is a new drug used to decrease referred pain in laparoscopy. As it has the potential to create metabolic acidosis and electrolyte disturbances, its safety and efficacy were investigated. Methods: Thirty adult patients scheduled for elective laparoscopic surgery were divided into 2 equal groups. Group A: was taken an average of 5 mg/kg oral tablets of acetazolamide one hour before induction while in group B: no acetazolamide was-given. Anesthetic protocol was standardized in the two groups using fentanyl intraoperatively. Patients Controlled Analgesia Device (PCA) was used postoperatively using morphine. The total doses of narcotics used intra and postoperatively were calculated and compared between both groups. Visual analogue pain scores (VAS) for incisional and referred pain were measured in both groups. Three arterial blood samples were taken and compared between both groups: the first sample was taken just after induction before abdominal insufflation, the second was taken one hour after abdominal insufflation, and the third was taken after recovery. Results: Referred pain was decreased significantly (measured by VAS) in group A than in group B during the first 6 hours after recovery, but after that time; there WAS no statistically significant difference between both groups. No significant difference between both groups as regard the VAS for incisional pain at any time. There was no statistically significant difference between both groups as regard the total intraoperative fentanyl required but the cumulative PCA consumption of morphine in 24 hr. was significantly higher in group B. The side effects related to morphine use were also higher in group B. The 3 arterial blood samples did not show any significant difference between both groups as regard the pH and electrolytes. Conclusion: Single oral administration of acetazolamide in an average dose of 5 mg/kg orally one hour before laparoscopic surgery does not cause pH or electrolytes changes. It decreases referred pain during the first 6 hours after recovery and this causes a decrease in the total doses of narcotics used postoperatively and its related side effects.