[Hypertensive crises. 2. Treatment].Ugeskr Laeger. 1995 Dec 18; 157(51):7140-5.UL
Hypertensive crisis is a rare condition with increased blood pressure and evidence of new or progressive severe end-organ damage. The patients should be admitted to hospital, and the blood pressure reduced gradually. Blood pressure should not be normalized, but a reduction in mean arterial pressure of 20-25% or to a diastolic blood pressure > 100-110 mmHg should be achieved. Patients at particular risk for further complications are elderly, patients with hypovolaemia, renal insufficiency, ischaemic heart disease and patients with neurological deficits. The ideal antihypertensive drug for any form of hypertensive crisis does not exist. If the patient can cooperate with oral treatment, nifedipine may be used, usually administered as capsules of 10 mg orally, producing a rapid and safe reduction in blood pressure of 25% within 10-15 minutes with a maximal action after 30-60 minutes. The dose may be repeated after 30 minutes in case of insufficient blood pressure response. Hypotension is rare. Nifedipine in combination with nitroglycerine is of special benefit in hypertensive pulmonary oedema. In cases of treatment failure or if the patient cannot cooperate with oral treatment, the choice of drug lies between labetalol and sodium nitroprusside. Nitroprusside is administered as continuous intravenous infusion, the drug is safe to use and is recommended in conditions where reduction of blood pressure must be performed with extreme caution such as in cases of cerebral infarction and intracranial hemorrhage. Infusion of nitroprusside for more than 48-72 hours is inexpedient because the metabolites of nitroprusside need monitoring as well. Parenteral drug therapy with labetalol is more simple than treatment with nitroprusside, but at the same time somewhat more difficult to titrate. Nitroglycerine is very suitable in moderate hypertension and ischaemic heart disease, but in severe hypertension with heart disease nitroprusside is the treatment of choice. Loop diuretics should not be used as first-line drugs, but only in conditions with evidence of volume-overload. Patients with hypertensive crisis most often show volume depletion which is aggravated by loop diuretics, therefore they should not be used routinely. When the blood pressure has been stabilized, an oral antihypertensive drug should be started concomitantly to a gradual reduction of the initial parenteral drug therapy.