USMLE Guide: Postoperative Nausea and Vomiting Prevention and Treatment

Introduction

Postoperative nausea and vomiting (PONV) are common complications following surgical procedures. They can lead to patient discomfort, delayed recovery, and prolonged hospital stays. This USMLE guide provides an overview of strategies for preventing and managing PONV.

Risk Factors for PONV

Certain patient and surgical factors increase the likelihood of developing PONV. These include:

• Female gender
• Non-smoking status
• History of motion sickness or PONV
• Use of certain anesthetic agents (e.g., volatile anesthetics, opioids)
• Abdominal or eye surgeries
• Prolonged surgery duration

Prevention Strategies

1. Patient Education: Inform patients about the risk of PONV and its management options.
2. Preoperative Assessment: Identify high-risk patients and tailor prevention strategies accordingly.
3. Pharmacological Prophylaxis:
   • 5-HT3 Receptor Antagonists: Administer ondansetron, granisetron, or dolasetron before surgery to reduce PONV risk.
   • Dexamethasone: Consider prophylactic use in high-risk patients.
   • NK1 Receptor Antagonists: Aprepitant or fosaprepitant may be used in patients at high risk for PONV.
   • Scopolamine: Apply transdermal patch 4 hours preoperatively for prolonged PONV prevention.
4. Regional Anesthesia: Utilize regional anesthesia techniques when appropriate to reduce PONV risk.
5. Avoidance of Known Triggers: Minimize known triggers such as volatile anesthetics, opioids, and nitrous oxide.

Treatment Approaches

If PONV occurs despite preventive measures, the following treatment options can be considered:

1. Non-Pharmacological Interventions:
   • Positioning: Place patients in a head-up position to promote blood flow and reduce nausea.
   • Ginger: Offer ginger supplements or ginger ale, known for its antiemetic properties.
   • Acupuncture: Consider acupuncture as an adjunctive therapy.
2. Pharmacological Treatment:
   • 5-HT3 Receptor Antagonists: Administer ondansetron or granisetron for acute PONV relief.
   • Dopamine D2 Receptor Antagonists: Use metoclopramide or prochlorperazine for refractory cases.
   • Antihistamines: Consider dimenhydrinate or promethazine as alternative options.
   • Corticosteroids: Administer dexamethasone as an adjunctive therapy for PONV treatment.
   • NK1 Receptor Antagonists: Aprepitant or fosaprepitant can be used if other treatments fail.

Conclusion

PONV is a common complication following surgery, but various preventive strategies and treatment options are available. Understanding the risk factors, implementing preventive measures, and utilizing appropriate treatment approaches can effectively manage PONV, improve patient outcomes, and enhance postoperative recovery.