Acute confusional state (delirium) : clinical studies in hip-fracture and stroke patients

Abstract: Acute confusional state (ACS) or delirium according to DSM-III-R holds a central position in the medicine of old age. ACS is a common and sometimes the only symptom of diseases and medical complications in the elderly patient.The aim of this study was to elucidate ACS in patients with femoral neck fractures and patients with acute stroke with regard to frequency, predictors, possible pathogenetic mechanisms, associated complications, assessment and documentary routines and the clinical outcome for the patients. An intervention program to prevent postoperative ACS based on our results was developed and evaluated.The main findings of the study were high frequencies of ACS in elderly patients with femoral neck fractures (61 %) and in patients with acute stroke (48 %). The main risk factors for ACS in patients with femoral neck fractures were old age, diseases and drug treatment interfering with cerebral cholinergic metabolism. There was no link between anaesthetic technique and ACS but the connection between peroperative hypotension, early postoperative hypoxia and ACS was close.In stroke patients the degree of extremity paresis and old age were independent ACS risk factors. ACS was commonly associated with post stroke complications such as myocardial infarction, pneumonia, urinary infection and urinary retention. In stroke patients there was a close connection between high hypothalamic-pituitary-adrenal axis (HPA-axis) activity and ACS. High HPA-axis activity and disturbances in the cerebral cholinergic system may be two important ACS mechanisms.A correct diagnosis is a prerequisite for proper treatment of ACS and its underlying causes. In the orthopaedic wards both physicians and nurses diagnosed and documented ACS poorly and therefore associated complications were insufficiently treated.The intervention program for postoperative ACS, aimed mainly at protecting the cerebral oxidative metabolism and thereby the cerebral cholinergic metabolism which is especially sensitive to hypoxia. Postoperative complications associated with ACS were also treated. The intervention resulted in reduced frequency, duration and severity of postoperative ACS and in shorter orthopedic ward stay for patients with femoral neck fractures.Key words: Acute confusional state, delirium, elderly