Postoperative Nausea and Vomiting (PONV) after Orthognathic Surgery: A Prospective Study

The prospective data of 25 patients were collected from department of oral and maxillofacial surgery, Ragas Dental College and Hospital, Chennai. The age of patients ranged between 15 to 50 years with a mean age of 32.5 years. The incidence of postoperative nausea and vomiting was assessed based on following factors: preanesthetic factors which include age, sex, previous history of motion sickness, habits like smoking, preanesthetic medication, ASA status, reaction to prior anesthetics, history of menstruation or harmone therapy. Intraoperative anesthetic factors which include duration of the procedure, type of anesthesia, inhalation agents used, neuromuscular blockers, IV anesthetics, antiemetics, reversal drugs, antibiotics and steroids used. Surgical factors include surgical site. Postoperative factors include analgesics used antiemetics, pain level. The patients were observed in the post anesthetic care unit for signs of nausea and vomiting during the first 24 hours after the surgical procedure under general anesthesia. The following conclusions can be derived from this study: 1. There was difference in postoperative nausea and vomiting with regard to age. Patients in young age group between 15 to 20 years showed high incidence of PONV compared to other groups. 2. Percentage of females with PONV was higher than males. The value was statistically not significant. 3. Only 2 patients were ASA II, of them one patient experienced PONV. 4. Only one patient had a history of motion sickness and experienced PONV. 5. PONV was high in patients undergoing bimaxillary surgeries compared to isolated jaw surgeries. 6. Incidence PONV increased with duration of the surgery. Longer the surgery, higher was the incidence of PONV. 7. Incidence of PONV was higher when an inhalation agent (halothane) was used along with nitrous oxide. 8. Increase in pain level increased the incidence of PONV. Although some risk factors mentioned above have been found to be significantly associated with incidence of postoperative nausea and vomiting, further studies are needed with a larger sample size to confirm these findings.