Classification: Cardiac inotropic agent
Action/Kinetics: Causes an increase in CO by increasing the force of contraction of the heart, probably by inhibiting cyclic AMP phosphodiesterase, thereby increasing cellular levels of c-AMP. It reduces afterload and preload by directly relaxing vascular smooth muscle. Time to peak effect: 10 min. t 1/2, after rapid IV: 3.6 hr; after IV infusion: 5.8 hr. Steady-state plasma levels: 2.4 mcg/mL by maintaining an infusion of 5-10 mcg/kg/min. Duration: 30 min-2 hr, depending on the dose. Excreted primarily in the urine both unchanged and as metabolites. Children have a larger volume of distribution and a decreased elimination half-life.
Uses: Congestive heart failure (short-term therapy in clients unresponsive to digitalis, diuretics, and/or vasodilators). Can be used in digitalized clients.
Contraindications: Hypersensitivity to amrinone or bisulfites. Severe aortic or pulmonary valvular disease in lieu of surgery. Acute MI.
Special Concerns: Safety and efficacy not established in children. Use with caution during lactation.
Side Effects: GI: N&V, abdominal pain, anorexia. CV: Hypotension, supraventricular and ventricular arrhythmias. Allergic: Pericarditis, pleuritis, ascites, allergic reaction to sodium bisulfite present in the product. Other: Thrombocytopenia, hepatotoxicity fever, chest pain, burning at site of injection.
Overdose Mangement: Symptoms: Hypotension. Treatment: Reduce or discontinue drug administration and begin general supportive measures.
Drug Interactions: Excessive hypotension when used with disopyramide.
How Supplied: Injection: 5 mg/mL