Postoperative nausea and vomiting in patients after craniotomy: incidence and risk factors.

OBJECT: The purpose of this study was to assess the incidence and risk factors of postoperative nausea and vomiting (PONV) after craniotomy because most available data about PONV in neurosurgical patients are retrospective in nature or derive from small prospective studies.

METHODS: Postoperative nausea and vomiting was prospectively assessed within 24 hours after surgery in 229 patients requiring supratentorial or infratentorial craniotomy. To rule out the relevance of the neurosurgical procedure itself to the development of PONV, the observed incidence of vomiting was compared with the rate of vomiting predicted with a surgery-independent risk score (Apfel postoperative vomiting score).

RESULTS: The overall incidence of PONV after craniotomy was 47%. Logistic regression identified female sex as a risk factor for postoperative nausea (OR 4.25, 95% CI 2.3-7.8) and vomiting (OR 2.62, 95% CI 1.4-4.9). Both the incidence of nausea (OR 3.76, 95% CI 2.06-6.88) and vomiting (OR 4.48, 95% CI 2.4-8.37) were increased in patients not receiving steroids. Postoperative nausea and vomiting occurred after infratentorial as well as after supratentorial procedures. The observed incidence of vomiting within 24 hours after surgery was higher (49%) than would be predicted with the Apfel surgery-independent risk score (31%; p = 0.0004).

CONCLUSIONS: The overall incidence of PONV within 24 hours after craniotomy was approximately 50%. One possible reason is that intracranial surgeries pose an additional and independent risk factor for vomiting, especially in female patients. Patients undergoing craniotomy should be identified as high-risk patients for PONV.