Hypertensive EMERGENCY
The situation is a true hypertension emergency when there is acute and life-threatening organ damage, such as hypertensive encephalopathy (headache, lethargy, seizures, coma), intra-cranial haemorrhage, aortic dissection, acute coronary syndromes (unstable angina/acute myocardial infarction), acute left ventricular failure with pulmonary oedema, or pre-eclampsia/eclampsia. The initial aim of treatment is to lower blood pressure in a rapid (within 2-6 hours), controlled but not overzealous way, to safe (not normal) levels – about 160mmHg systolic and 100mmHg diastolic, with the maximum initial fall in blood pressure not exceeding 25% of the presenting value. Too rapid a fall in pressure may precipitate cerebral or myocardial infarction, or acute renal failure.
Hypotensive agents should be administered intravenously when organ damage is potentially life-threatening. All patients should be admitted to a high dependency or intensive care bed, for continuous BP monitoring. The choice of drug will frequently depend on the underlying cause or the organ most compromised. In many instances, patients will be salt and water deplete and will require fluid replacement with normal saline in addition to antihypertensive agents.