[Doxapram-induced changes in circulation and myocardial efficiency (author's transl)]

The effects of Doxapram 2.0 mg/kg intravenously on circulation and myocardial oxygen supply were studied in 9 anaesthetized closed chest dogs. Immediately after Doxapram increases in heart rate (maximum+40.5%, 1st min), mean aortic pressure (+49%, 3rd min), cardiac index (+18%, 3rd min), total peripheral resistance (+32%, 3rd min), pulmonary arterial pressure (+48%, 1st min), left ventricular end-diastolic pressure (+79%, 1st min), myocardial blood flow (+38%, 3rd min), myocardial oxygen consumption (+74%, 1st min) and left ventricular work (+76%, 1st min) were observed. The changes in heart rate, mean aortic pressure, myocardial blood flow, myocardial oxygen consumption and heart work were persistent up to 20 min after Doxapram 2.0 mg/kg intravenously. Max dp/dt, coronary vascular resistance and the myocardial efficiency were not influenced after Doxapram.