doi:10.1093/bja/ael094 Advance Access publication May 2, 2006 Emergence delirium in adults in the post-anaesthesia care unit

Background. Emergence delirium in the post-anaesthesia care unit (PACU) is poorly under-stood. The goal of this prospective study was to determine frequency and risk factors of emer-gence delirium in adults after general anaesthesia. Methods. In this prospective study, 1359 consecutive patients were included. Contextual risk factors and occurrence of delirium according to the Riker sedation scale were documented. Groups were defined for the analysis according to the occurrence or not of agitation, then after exclusion of patients with preoperative anxiety and neuroleptics, or both, and antidepressants or benzodiazepines treatments. Results. Sixty-four (4.7%) patients developed delirium in the PACU, which can go from thrashing to violent behaviour and removal of tubes and catheters. Preoperative anxiety was not found to be a risk factor. Preoperative medication by benzodiazepines (OR=1.910, 95 % CI=1.101–3.315, P=0.021), breast surgery (OR=5.190, 95 % CI=1.422–18.947, P=0.013), abdominal surgery (OR=3.206, 95 % CI=1.262–8.143, P=0.014), and long duration of surgery increased the risk of delirium (OR=1.005, 95 % CI=1.002–1.008, P=0.001), while a previous history of illness and long-term treatment by antidepressants decreased the ris