Introduction

Haemodynamic control is an essential component of safe perioperative care. The importance of hypertension in the perioperative period has long been recognized and it is known that sympathoa-drenal activation and perioperative hypertension may lead to adverse effects, particularly myocardial ischaemia and haemorrhage. These adverse events are themselves linked to poor outcomes, yet they may be prevented by good cardiovascular control.

Even in those patients who are normotensive before surgery, perioperative surgical stress may have an adverse effect. This is particularly true of cardiac surgery, where the impact of sternotomy and handling the great vessels in the phase before cardiopulmonary bypass (CPB) may be provocative in many patients.

Preoperative management

Manypatients who present for coronary revascularization do not demonstrate adequate blood pressure control according to current recommendations, despite these having been validated by observed reductions in morbidity and mortality.

Effects of hypertension

Primary or essential hypertension may result from a complex interaction of renal, neurogenic, endocrine and cardiovascular factors, particularly alterations in the activity of the vascular endothelium. Specific conditions may also be responsible. These causes of secondary hypertension are important because they may have implications for other aspects of perioperative care. However, the effects of hypertension, particularly when longstanding, may precipitate significant problems in the perioperative period. Renal disease may be associated both with the development of high blood pressure and adverse effects resulting from established hypertension.