Pre-operative co-morbidity and postoperative survival in the elderly: beyond one lunar orbit.

Mortality is a good measure of killing, but it is a poor measure of cure, palliation or the maintenance of function. Nevertheless, it has remained the primary metric of hospital care for 200 years. This article discusses the factors that contribute to mortality risk and survival trajectories, as well as the increasing recognition that surgery kills for months after the last suture is tied. This article discusses how disparate factors can usefully combine to generate an 'elderly' group with a monthly mortality in excess of 1% and a median life expectancy less than 3.5 years. A downloadable spreadsheet is provided that combines risk factors to generate mortality risks and their associated survival curves, emphasising the importance of looking beyond one postoperative month.