Table 1. Postoperative nausea and vomiting (PONV) risk factors in adults related to patient, anesthesia, and surgery.

Category	Risk factors in adults
Patient related	Female gender History of PONV Motion sickness Non-smoking status Age <50 years
Anesthesia related	Anesthesia technique (general anesthesia results in higher incidence of PONV than does regional anesthesia) Prolonged duration of anesthesia Volatile agents Nitrous oxide (>50%) Intraoperative and postoperative opioid analgesics Increased doses of neostigmine (>3 mg)
Surgery related	Extended surgical procedures Surgery categories (e.g. neurosurgery, laparoscopic surgery, cholecystectomy, intra-abdominal surgery, and gynecological surgery)