LAUSR

The prophylaxis and treatment of postoperative pain to enhance patient comfort has been a primary goal of anesthesiologists for the last decades; however, avoiding postoperative nausea and vomiting (PONV) is, from a patient's perspective, a highly relevant and equally important goal of anesthesia. Recent consensus-based guidelines suggest the assessment of risk factors including female gender, postoperative opioid administration, non-smoking status, a history of PONV or motion sickness, young patient age, longer duration of anesthesia, volatile anesthetics and the type of surgery and reducing the patient's baseline risk (e.g. through the use of regional anesthesia and administration of non-opioid analgesics as part of a multimodal approach). In general, a liberal PONV prophylaxis is encouraged for adult patients and children, which should also be administered when no risk assessment is made. The basis for every adult patient should be a standard prophylaxis with two antiemetics, such as dexamethasone in combination with a 5-HT3 receptor antagonist. In patients at high risk, this should be supplemented by a third and potentially a fourth antiemetic prophylaxis with a different mechanism of action. A recently published comprehensive Cochrane meta-analysis comparing available antiemetic prophylaxes reported the highest effectiveness to prevent PONV for the NK1 receptor antagonist aprepitant (relative risk, RR 0.26), followed by ramosetron (RR 0.44), granisetron (RR 0.45), dexamethasone (RR 0.51) and ondansetron (RR 0.55), thereby revising the dogma that every antiemetic is equally effective. Adverse events of antiemetics were generally rare and reported in less than half of the included studies, yielding a low quality of evidence for these end points. In general, combinations of different antiemetics were more effective than single prophylaxes. In children above 3 years of age, the same principles should be applied as in adults. For these patients, there is a high degree of evidence for the combination of dexamethasone and 5‑HT3 receptor antagonists. When PONV occurs, the consensus guidelines suggest that antiemetics from a class different than given as prophylaxis should be administered. To decrease the incidence of PONV and increase the quality of care, the importance of the implementation of institutional-level guidelines and protocols as well as assessment of PONV prophylaxis and PONV incidence is highly recommended.