Preliminary results with amrinone in perioperative low cardiac output syndrome

The hemodynamic parameters of 24 cardiosurgical patients with low cardiac output syndrome (LCOS) after weaning from bypass were evaluated retrospectively. These patients were additionally treated with amrinone if the conventional therapy with catecholamines and vasodilators did not reach satisfying hemodynamic results. 14 patients underwent aorto-coronary bypass surgery, 10 patients underwent valve repair. Their disability by NYHA class was III and IV. One third of these patients died between the first and the fifth day postoperatively. Hemodynamic assessment was performed after weaning from bypass and after the start of amrinone therapy and was continued the first 24 hours in the intensive care unit, as long as the patients were dependent on amrinone. The platelet count was determined every eight hours after surgery. Under the supplementary therapy with amrinone we found an increase of the arterial pressure and cardiac index and decrease of heart rate and total peripheral resistance. These salutary hemodynamic changes could be sustained in the postoperative period. The platelet count dropped from nearly 100,000/mm3 in mean (first measurement post-op.) to 58,000 in mean (the lowest value during 48 hours on intensive care). 2 patients showed a decrease to 11,000 and 15,000/mm3 with petechial bleedings. These findings indicate that on the one hand amrinone seems to be a promising drug in cases of severe LCOS when conventional therapy fails, but on the other hand a marked decrease of the platelets can occur. Therefore a frequent control of platelet count has to be performed when using amrinone.