Minibolus diazoxide in the management of severe hypertension in pregnancy.

Severe hypertension poses immediate and potentially lethal maternal risks. Prompt reduction in blood pressure should be an urgent priority, with concomitant anticonvulsant therapy. Previous reports confirm intravenous diazoxide to be an effective agent. Concern exists over adverse reactions associated with bolus injection of the standard 300 mg dose. Many physicians are unaware that diazoxide may be given in increments. This study describes the use of diazoxide in 34 patients with severe preeclampsia. They received minibolus injections of 30 mg every 1 to 2 minutes. The maximum dose required was 150 mg and no maternal hypotension occurred. Maternal side effects were minimal and no cases of fetal distress occurred; a perinatal mortality was zero. It appears that minibolus diazoxide rapidly lowers maternal blood pressure without the adverse effects described with a standard bolus dose. Its advantages are contrasted with the limitations of conventional hydralazine therapy.