Six months of shivering in a district general hospital.

Of 2595 patients admitted to a recovery room in Derbyshire Royal Infirmary over a 6-month period, 164 (6.3%) shivered postoperatively. Data regarding the anaesthetic techniques to which these patients had been subjected were gathered from the Derby Anaesthetic Audit System. Subsequent analysis demonstrated the importance of a number of factors that led to shivering, including male gender, anaesthetic techniques involving spontaneous ventilation, and anticholinergic premedication. The administration of pethidine, alfentanil or morphine intra-operatively reduced the incidence of shivering postoperatively.