# Risk factors for postoperative nausea and vomiting after general anesthesia: a systematic review and meta-analysis

## TL;DR

This study identifies risk factors for postoperative nausea and vomiting after general anesthesia, helping clinicians better predict and manage this common complication.

## Contribution

A systematic review and meta-analysis quantifying patient, anesthetic, and surgical risk factors for postoperative nausea and vomiting.

## Key findings

- Female gender, motion sickness, and non-smoking status are significant patient-related risk factors for PONV.
- Anesthetic factors like patient-controlled analgesia and volatile anesthetics increase PONV risk.
- Surgical procedures such as breast surgery and cholecystectomy are associated with higher PONV rates.

## Abstract

This systematic review and meta-analysis aimed to quantitatively analyze and summarize the risk factors of postoperative nausea and vomiting (PONV) in patients undergoing general anesthesia.

Literature screening, data extraction, and statistical analysis were conducted by an independent investigator. Meta-analyses were conducted for included studies using a random-effects method and generic inverse variance. All risk factors analyzed in the multifactorial regression models of the included studies were included in the meta-analysis to calculate the combined OR and 95% CI.

We included 31 studies (n = 355,117). Patient-specific factors included female gender (OR 2.39), motion sickness (2.08), non-smoking (1.70), migraine (1.38), BMI (1.06), age (0.98), ASA II (0.97) and ASA III (0.84). Anesthetic factors included patient-controlled analgesia (1.51), volatile anesthetics (1.46), postoperative-opioids (1.32), duration of anesthesia (1.31), intraoperative-opioids (1.22), N2O (1.12), intravenous-anesthesia (1.12), fentanyl (1.07), preventive antiemetic (0.84), and hormone medications (0.81). Of the 16 surgical factors, breast surgery (2.13), cholecystectomy (2.07), abdominal surgery (1.37), gynecology surgery (1.34), and surgical duration (1.13) were statistically significant. The remaining surgical factors, namely plastic (2.01), ophthalmologic surgery (2.0), neurosurgery (1.71), head/neck surgery (1.38), ear/nose/throat surgery (1.34), orthopedics (1.27), thyroid surgery (1.26), laparoscopic surgery (1.14), urological surgery (0.99), and postoperative pain (0.59) was not statistically significant.

This study revealed patient-related, procedure-related, and anesthesia-related significant risk factors for PONV. This may provide a basis for clinical prevention, but a rigorously designed prospective study should be performed to confirm the findings of this study.