Complications and morbidity of controlled hypotension.

The surgeon may praise the anaesthetist for a bloodless field and the patient may awaken with a good operative result; but, has any particular risk been taken? Indeed, can the risk of using deliberate hypotension be assessed? A major problem is that many papers give an account of groups of patients safely undergoing surgery facilitated by controlled hypotension. However, each paper contains one or two cases where death has occurred attributable to the hypotensive technique employed (Enderby, 1961; Hugosson and Hogstrom, 1973; Prys-Roberts et al., 1974; Rollason and Hough, 1960; Warner, Shumrick and Caffrey, 1970; Way and Clarke, 1959). The areas of risk of complication and morbidity may be categorized: (A) Risks of major organ underperfusion. (B) Surgical complications following hypotension.