Epidemiology in anaesthesia: a method for predicting hospital mortality.

Data on 13 043 operations were abstracted from 108 878 anaesthetic records in the Cardiff Anaesthetic Record System. Nine groups of surgical operations with high mortality in hospital were identified. These records were analysed using a logistic regression model to determine the probability of death in hospital. Variables included in the model were age, sex, elective or emergency operation and five intercurrent diseases. The significance of individual variables was assessed: age was the most important single variable in six of the nine operation groups. The model was used to calculate the risk of death in hospital for individuals with specific characteristics. With further development, this technique might be used by clinicians at other centres to predict the outcome for patients under their care.