Mechanisms underlying postoperative nausea and vomiting and neurotransmitter receptor antagonist-based pharmacotherapy.

Postoperative nausea and vomiting (PONV) is one of the most common and distressing complications following surgery, and understanding the mechanism(s) underlying PONV is essential to providing optimal prophylaxis and/or treatment of PONV. The knowledge base of PONV physiology has significantly expanded over the past decade. This article reviews the risk factors for the development of PONV and the mechanisms of action of pharmacological agents (including antagonists of serotonin 5-HT(3), dopaminergic D(2), histamine H(1), muscarinic cholinergic, opioid and neurokinin NK(1) receptors) for the management (i.e. prophylaxis and treatment) of PONV. NK(1) receptor antagonists, with their unique mechanism of action, are a particularly promising area of research as they appear to be efficacious in preventing PONV during both the early and the late postoperative periods. A successful PONV management strategy includes: (i) identifying patients at risk; (ii) keeping the baseline risk low; and (iii) using a combination of antiemetics acting on different receptors in moderate- to high-risk patients.