Is 'anxiety sensitivity' predictive of postoperative nausea and vomiting? A prospective observational study

BACKGROUND Postoperative nausea and vomiting (PONV) is an extremely distressing side effect for patients. Despite PONV prophylaxis guided by well established scoring systems, the incidence of PONV is still high. OBJECTIVE The aim of the current study was to investigate the predictive value of anxiety sensitivity as an additional independent risk factor for PONV in patients with an increased risk of PONV. DESIGN A noninterventional, observational study. SETTING A tertiary care university hospital. PATIENTS Patients with an increased risk of PONV (i.e. female, nonsmoking) undergoing elective surgery (general, gynaecological, urological, musculoskeletal or neurosurgical) under general anaesthesia. MAIN OUTCOME MEASURES The number of patients with anxiety sensitivity assessed pre-operatively with the Anxiety Sensitivity Index-3 questionnaire, the number of patients experiencing PONV, predictive value of anxiety sensitivity compared with other established risk factors for PONV. RESULTS Some 41.5% of the patients experienced PONV within the first 24 h after surgery. In these patients increased anxiety sensitivity (Anxiety Sensitivity Index-3 score higher than seven points) was associated with a five-fold increase in the odds ratio (OR) for PONV. From the regression model, the risk of PONV was increased by lack of PONV prophylaxis (OR, 3.68), the postoperative administration of opioids (OR, 3.60) and patient age (OR, 1.03), but laparoscopic surgery did not increase the risk. CONCLUSION In addition to the well established risk factors, anxiety sensitivity can help to predict the risk of PONV. It seems justifiable to add psychological factors such as anxiety sensitivity to PONV risk-scores. PONV prophylaxis should be considered when anxiety sensitivity is high.