[Therapy of cardiogenic shock with dobutamine and nitroglycerin]

Pulmonary artery, right atrial and systemic arterial pressures, cardiac output and total peripheral resistance were measured in 12 patients with the clinical picture of cardiogenic shock. The patients were then given dobutamine alone or in combination with various high doses of nitroglycerin. In seven patients with severe valvar malfunction, cardiac output rose significantly after dobutamine from 4.0 to 4.5 l/min . 1.73 m2, without changes in systemic arterial pressure and left and right-ventricular filling pressures. Additional intravenous infusion of nitroglycerin (1.5-3.0 mg/h) raised cardiac output to 4.7 l/min (P less than 0.01), reduced filling pressure, and stabilized systemic arterial pressure. Further increase in nitroglycerin dose (3.0-6.0 mg/h) reduced the filling pressures considerably, but cardiac output and systemic arterial pressure fell. In the five patients with severe myocardial damage, cardiac output rose after dobutamine (P less than 0.05), but could not be further enhanced by nitroglycerin. When the dose was increased, left and right-ventricular filling pressures fell clearly, but at the same time there was also a fall in systemic arterial pressure. The optimal left-ventricular filling pressure is unexpectedly high (28 mm Hg) in cardiogenic shock. It is concluded that the treatment of cardiogenic shock with dobutamine (7 micrograms/kg . min) in combination with low nitroglycerin dose (1.5-3.0 mg/h) causes definite improvement in haemodynamics, symptoms and prognosis.