[Sublingual nitroglycerin or intravenous enalaprilat in preclinical treatment of hypertensive patients with pulmonary edema].

In a prospectively designed randomized study, we compared the efficacy of sublingual nitroglycerine and intravenous enalaprilat in the out-of-hospital treatment of 46 hypertensive patients with pulmonary edema (defined as rales over both lungs and systolic blood pressure > 200 mm Hg and diastolic blood pressure > 100 mg). The out-of-hospital treatment consists of oxygen (6 Ll/min) via a face mask, furosemide 80 mg i.v., opioids 10 mg s.c., and either sublingual nitroglycerine (n = 23; initial dose: 0.8 mg; repetitive application of 0.8 mg every 10 min until a cumulative dose of 3.2 mg) or intravenous enalaprilat (initial dose: 2.5 mg; repetitive application of 2.5 mg every 30 min until a cumulative dose of 10 mg). The aim of the antihypertensive treatment was a reduction of systolic blood pressure below 160 mm Hg and diastolic blood pressure below 90 mm Hg until admission to the emergency department. In the emergency room, an arterial and venous blood sample was taken to determine the respiratory (pO2, pCO2) and metabolic status (pH value; base-excess; serum lactate) of the patient. Successful antihypertensive treatment was observed in 13/23 (57%) patients of the enalaprilat group and 15/23 (65%) patients of the nitroglycerine group (p = 0.54). Systolic and diastolic blood pressure on admission were similar in both treatment groups (systolic RR: enalaprilat: 179 [31] mm Hg; nitroglycerine: 184 [38] mm Hg; p = 0.59; diastolic RR: enalaprilat: 96 [14] mm Hg; nitroglycerine: 101 [14] mm Hg; p = 0.12). No significant differences were observed between the enalaprilat and the nitroglycerine groups concerning respiratory and metabolic parameters on admission (pO2: 67 [15] vs. 64 [17] mm Hg; p = 0.50; pCO2: 46 [9] vs. 47 [13]; p = 0.75; pH value: 7.27 [0.12] vs. 7.27 [0.09]; p = 0.98; BE: -4.2 [3.7] vs. -5.7 [4.1]; p = 0.23; lactate: 4.2 [3.3] vs. 4.2 [2.7]; p = 0.98). Intravenous enalaprilat did not exhibit any advantage compared to nitroglycerine in terms of blood pressure reduction or respiratory and metabolic parameters on admission to the emergency room. We conclude that enalaprilat is no substitute for nitroglycerine in the out-of-hospital treatment of hypertensive patients with pulmonary edema.