Hypertension in the intensive care unit.
OBJECTIVE
The severity of hypertensive crises is determined by the presence of target organ damage rather than the level of blood pressure. Hypertensive urgencies with no signs of organ dysfunction can therefore be distinguished from hypertensive emergencies in which the presence of severe end-organ damage requires prompt therapy. Hypertensive emergencies include acute aortic dissection, hypertensive encephalopathy, acute myocardial ischaemia, severe pulmonary oedema, eclampsia, and acute renal failure.


BACKGROUND
Malignant hypertension is a severe form of hypertensive emergency demanding special consideration because of the risks of permanent blindness and renal failure. Catecholamine excess and postoperative hypertension may also sometimes require urgent treatment. The management of patients with hypertensive emergencies must be ensured in an intensive care unit, and must include the parenteral administration of antihypertensive drugs and accurate blood pressure monitoring.


CONCLUSIONS
Except for acute aortic dissection, the recommended goals of treatment are a reduction of mean arterial pressure by no more than 20% during the first few hours, because an abrupt fall in blood pressure in patients with preexisting hypertension may induce severe ischaemic injury in major organs as a result of the chronic adaptation of autoregulation mechanisms. Hypertension in the context of acute stroke should be treated only rarely and cautiously because of the presence of impaired autoregulation.
Slama
Michel
M
INSERM ERI 12, Amiens, France. slama.michel@chu-amiens.fr
Modeliar
Santhi Samy
SS
D000208:Acute Disease; D058186:Acute Kidney Injury / Q000209:etiology; D000784:Aortic Dissection / Q000209:etiology; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001014:Aortic Aneurysm / Q000209:etiology; D001794:Blood Pressure; D003422:Critical Care; D004461:Eclampsia / Q000503:physiopathology; D004630:Emergencies; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications* / Q000188:drug therapy* / Q000503:physiopathology; D020343:Hypertensive Encephalopathy / Q000209:etiology; D007362:Intensive Care Units; D008297:Male; D017202:Myocardial Ischemia / Q000209:etiology; D011247:Pregnancy; D011654:Pulmonary Edema / Q000209:etiology; D020521:Stroke / Q000209:etiology
D000959:Antihypertensive Agents