COMPARISON OF PROSTACYCLIN AND SODIUM-NITROPRUSSIDE FOR THE TREATMENTOF HEART-FAILURE AFTER CARDIAC-SURGERY

Objective: To study the effects of the two vasodilators, prostacyclin and sodium nitroprusside, on central hemodynamics in heart failure aft er cardiac surgery. Design: Randomized cross-over study. Setting: Mult i-institutional university hospital. Participants: Ten patients. Inclu sion criteria: cardiac index less than 2.5 L/min/m(2); pulmonary capil lary wedge pressure greater than 15 mmHg, systemic vascular resistance index greater than 2,500 dynes . s . cm(-5)/m(2), and treatment with inotropic support. Five patients were treated with intraaortic balloon counterpulsation. Interventions: After control measurements, mean art erial pressure was decreased by 10% to 20% with each vasodilator in ea ch patient. Measurements and Results: Sodium nitroprusside induced dec reases in mean pulmonary arterial pressure (-21%), pulmonary capillary wedge pressure (-29%), central venous pressure (-17%), and systemic v ascular resistance (-25%), and increases in cardiac output (+7%) and s troke volume (+6%) compared with control. Prostacyclin decreased mean pulmonary arterial pressure (-14%), pulmonary capillary wedge pressure (-19%), central venous pressure (-7%), and systemic (-40%) and pulmon ary (-25%) vascular resistances, whereas cardiac output (+25%) and str oke volume (+22%) increased compared with control. Prostacyclin, compa red with sodium nitroprusside, induced a more pronounced increase in c ardiac output and stroke volume, associated with less pronounced decre ases in cardiac filling pressures and more profound decreases in syste mic and pulmonary vascular resistances. Conclusion: Prostacyclin appea rs to be a useful agent, superior to sodium nitroprusside, in the trea tment of postoperative heart failure in patients with normal or mildly elevated cardiac filling pressures, where vasodilator treatment is in dicated. (C) 1995 by W.B. Saunders Company