A modern look at hypertension and anaesthesia

Hypertension is common among patients presenting for surgery, and is frequently untreated or inadequately treated. While the approach to the patient with hypertension presenting for anaesthesia is controversial, and the evidence base for appropriate clinical decisions is weak, this is a problem that practising clinical anaesthetists face on a regular basis. This article seeks to present a unified approach to the problem of a hypertensive patient presenting for surgery, and offers suggestions as to the appropriate management options. As far as possible, the recommendations contained in this article have been based on the best available evidence. The authors suggest that moderate degrees of hypertension (up to 180/120 mmHg), without obvious target organ disease, should never be grounds for postponing surgery. Even with greater degrees of hypertension, the relative risk of postponing surgery should always be considered. There is little evidence that, in patients without target organ disease, delaying surgery in order to establish antihypertensive therapy is beneficial. For very severe hypertension, the benefits of delaying surgery to establish adequate hypertensive control must be weighed against the risk of delayed surgery. Where a surgical delay is considered, adequate time to establish appropriate blood pressure control must be allowed, and there is no place for sudden “cosmetic” correction of blood pressure immediately prior to anaesthesia. Previously undiagnosed hypertension, presenting for the first time at surgery, requires a basic investigation of target organ disease prior to anaesthesia, and appropriate subsequent follow-up referral for further management.