Anaes · Postoperative nausea & vomiting
Postoperative nausea & vomiting (PONV)
Also known as PONV · Apfel score · Ondansetron · Dexamethasone · Aprepitant · Antiemetic prophylaxis
Exam-exhaustive PONV: Apfel four factors with exact risk steps, paediatric modifiers, prophylaxis by receptor class with mg/kg doses, different-class rescue, TIVA and opioid-sparing, and risk-stratified not universal triple therapy.
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Red flags
- Apfel 4 ≈ 80% baseline risk — needs multimodal prophylaxis, not a single ondansetron.
- Rescue must be a different receptor class from prophylaxis; do not repeat ondansetron immediately.
- PONV is the leading anaesthetic cause of day-case failure — prevent it deliberately.
- Risk-stratify: low-risk patients do not need universal triple therapy.
- TIVA + opioid-sparing cut baseline risk before any antiemetic is drawn up.
Meet the patient
A 38-year-old non-smoking woman, with a history of motion sickness, arrives for a day-case laparoscopic cholecystectomy and expects postoperative opioids. That is four Apfel factors, a baseline risk near 80%, and a near-certain unplanned admission if you run a volatile-opioid anaesthetic with a single ondansetron.[1]
Two ideas frame every PONV decision: risk is a number you compute, not a feeling (Apfel gives you the percentage), and the cheapest antiemetic is the one you never need (TIVA and opioid-sparing cut the baseline risk before any drug is drawn up). Hold those two and the formulary falls into place.[1]
References5ShowHide
- [1]Apfel CC, Läärä E, Koivuranta M, Greim CA, Roewer N. A simplified risk score for predicting postoperative nausea and vomiting: conclusions from cross-validations between two centers Anesthesiology, 1999.PMID 10485781
- [2]Gan TJ, et al. Fourth Consensus Guidelines for the Management of Postoperative Nausea and Vomiting Anesth Analg, 2020.PMID 32467512
- [3]Pandit JJ, et al. 5th National Audit Project (NAP5) on accidental awareness during general anaesthesia: summary of main findings and risk factors Br J Anaesth, 2014.PMID 25204697
- [4]Apfel CC, et al. A factorial trial of six interventions for the prevention of postoperative nausea and vomiting N Engl J Med, 2004.PMID 15190136
- [5]Eberhart LHJ, et al. The development and validation of a risk score to predict the probability of postoperative vomiting in pediatric patients Anesth Analg, 2004.PMID 15562045