Ambulatory surgery: PONV Rx

Risk factors for PONV can be divided into three main categories: patient-related, anesthetic-related, and surgery-related.

Patient-related factors include female sex, nonsmoking status and history of PONV or motion sickness. Female sex is the strongest independent predictor for postoperative nausea, vomiting, use of antiemetic rescue treatment and overall PONV. Some texts also consider obesity, pregnancy and diabetes as risk factors, though these have not been supported in the literature.

Anesthetic-related factors include use of inhalation agents, use of nitrous oxide, and use of intraoperative and postoperative opioids. There do not appear to be significant differences between specific opioids, but rather a dose-related increase in the incidence of PONV.

Surgery-related factors include duration of surgery and type of operation. Many surgeries are cited as having higher incidence of PONV, although this may be due to underlying factors such as prolonged exposure to emetogenic anesthetics or higher doses of intra-operative opioids. Laparoscopic cholecystectomy, hysterectomy, and strabismus surgery in children are among the few surgeries that do have evidence of increased PONV.