Opisthotonus and other unusual neurological sequelae after outpatient anaesthesia

Four patients who developed unusual neurological sequelae after outpatient anaesthesia are described. Propofol is strongly implicated as the cause. All four patients were female with no previous history of psychiatric disorder or neurological disease, unpremedicated, and had procedures of duration less than 20 minutes. Hyperreflexia and hypertonicity were present postoperatively and the reactions appeared to be triggered by an external stimulus. Three patients were examined by a neurologist and had a normal electroencephalograph. Two patients were on the same operating list; quality control was carried out on the anaesthetic agents used, and blood samples sent for toxicology showed no abnormalities. Mechanisms underlying these reactions are discussed.