Comparison Between Isosorbide Dinitrate in Aerosol and in Tablets for the Treatment of Hypertensive Emergencies

Abstract

Sixty patients with a hypertensive emergency (mean arterial pressure >130 mm Hg and evidence of target organ damage) were randomly divided into two groups of 30 patients each. Group A received 1.25 mg of isosorbide dinitrate aerosol upon arrival and a second dose 15 minutes later when the mean arterial pressure reduction was < 15%. Group B received a single 5 mg tablet of sublingual isosorbide dinitrate. Electrocardiography was performed in both groups prior to and 30 minutes after the medication. Blood pressure was monitored for 6 hours. Blood pressure in Group A patients decreased in an average time of 10 minutes from 191 +/- 12/122.3 +/- 5 to 151.5 +/- 9.2/93 +/- 4 mm Hg, p < 0.005. Mean arterial pressure decreased by 22.8%: 145 +/- 7 to 112 +/- 7.5 mm Hg, p < 0.005. No adverse effects occurred. Five patients in Group B did not respond; in the rest of the group blood pressure decreased 45 minutes after receiving the medication from 194 +/- 8/125 +/- 5.5 to 160 +/- 11/98 +/- 6 mm Hg; p < 0.005. Mean arterial pressure decreased by 20.1%: 148.3 +/- 12 to 118.6 +/- 9 mm Hg, p < 0.002; ten patients suffered headache. Three patients in Group A had a subepicardial lesion in the first electrocardiograph, which disappeared with the use of the aerosol. In Group B, electrocardiography results were normal. These results seem to indicate that isosorbide dinitrate aerosol is better than tablets for the treatment of patients with a hypertensive emergencies.

Treatment of hypertensive urgencies and emergencies

“…Because of its pharmacologic actions, nitroglycerin infusion may be particularly benefi cial in patients with coronary artery disease with or without hypertension. Isosorbide dinitrate therapy has also been used for the immediate treatment of severe hypertension [27], but its precise role and guidelines on how to use it are not fully delineated.…”

Management of Hypertensive Crises

“…One alternative to the intravenous route is to administer 1.25 mg of isosorbide dinitrate aerosol upon arrival. 17 If BP does not decrease with use of nitroglycerin, then nitroprusside should be added to the regimen. Nevertheless, the adverse reactions of nitroprusside may include baroreflex activation, causing tachycardia, and coronary steal phenomenon, with worsening of ischemia in areas with fixed coronary stenosis.…”