COMPARISON OF POST-OPERATIVE NAUSEA AND VOMITING (PONV) AMONG PATIENTS UNDERGOING TYMPANOPLASTY UNDER LOCAL ANAESTHESIA.

Background: The most important side effect of Ondansetron medicine is hypersensitivity reactions. Dexamethasone, is cheap and has no serious side effects. Dexamethasone is less widely used for control of post-operative nausea and vomiting (PONV) by anaesthetists in gastrointestinal patients, perhaps because of a lack of proven efcacy in these patients. Aims: To compare the PONV among patients undergoing tympanoplasty under local anaesthesia. Methodology: A Randomized control study was conducted in patients undergoing tympanoplasty. 60 subjects were randomly divided into two groups- Group O (n=30): received intravenous Ondansetron 4mg & Group D (n=30): received intravenous dexamethasone 8mg. Patients data was collected about age, gender, ASA, duration of anesthesia, duration of the operation, blood pressure before and after the operation, respiratory rate before and after the operation, saturation of peripheral oxygen (SPO2) before and after the operation. All instances of nausea and vomiting was recorded carefully every few hours for 24 hours until the discharge of patient from ward. Side effects were observed and registered. Results: The episodes of nausea highest in Group D at 0 to 2 hours, 2 to 6 hours and 6 to 24 hours; the retching and nausea was similar in both group D and group O. The Dexamethasone group has been having statistically signicant higher number of nausea, retching and vomiting compared to Ondansetron group at 0 to 2 hours and 2 to 6 hours; however, it there was no statistical difference at 6 to 24 hours. The nausea severity score showed higher score in dexamethasone group, with 66.67% in Group D and 53.3% in Group O at 0 to 2 hours having severe scores of 1 to 3; 66.67% in Group D and 50% in Group O at 2 to 6 hours having severe scores of 1 to 3 & 33.3% in Group D and 23.3% in Group O at 6 to 24 hours having severe scores from 1 to 3. However, these were not statistically signicant. The need for antiemetic rescue showed that group D needed more rescue than group O at 0 to 2 hours, however, at 2 to 6 hours Group O had few more rescues needed than Group D. At 6 to 24 hours there were no need for any rescue in Group O compared to 3 in group D. These differences were not statistically signicant in both groups. In total Group O had 11 recuse injection (36.7%) and Group D had 18 rescue injection (60%). Ondansetron was better Conclusion: in preventing PONV than Dexamethasone in the early stages post-surgery, however, it was similar when seen in the up to 24 hours post-surgery.