The use of dopexamine after cardiac surgery: acute and long-term effects in patients with impaired cardiac function.
The haemodynamic efficacy of dopexamine, a beta 2-adrenergic agonist with dopaminergic activity, was evaluated during dosetitration and longterm infusion in 20 cardiosurgical patients with low cardiac output following coronary artery bypass grafting and/or valve replacement or repair. After infusion of four doses (1, 2, 4, and 6 micrograms/kg/min), the dose producing the optimal response was administered for up to 36 h. Dopexamine infusion resulted in a dose-dependent significant increase in cardiac index (CI: 2.2-->3.3 L/min/m2) associated with a marked reduction of systemic vascular resistance (SVR: 1820-->1144 dyn.sec.cm-5). Heart rate increased significantly (HR: 89-->117 beats/min), while mean arterial blood pressure remained unchanged (MAP: 94-->89 mmHg). Unwanted effects (tachycardia and hypotension) were chiefly seen at higher doses (-->4 micrograms/kg/min). The beneficial haemodynamic effects were well maintained during the extended infusion period up to 36 hours at a mean dopexamine dose of 2.8 micrograms/kg/min. At these low doses, the positive chronotropic response to the drug remained within the limits of clinical acceptability. During long-term infusion up to 36 hours there was no indication of tolerance or an effect attenuation. It can be concluded that dopexamine acting as "inodilator" with dopaminergic properties is an useful adjunct to the pharmacological spectrum in the management of low-output states following cardiac surgery.
Dept. of Cardiothoracic Surgery, German Heart Institute Berlin, Germany.
N
N
Friedel
R
R
Wenzel
G
G
Matheis
R
R
Hetzer
D000322:Adrenergic Agonists / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D002303:Cardiac Output, Low / Q000188:drug therapy* / Q000209:etiology; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D004298:Dopamine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D004334:Drug Administration Schedule; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D013997:Time Factors; D016896:Treatment Outcome
D000322:Adrenergic Agonists; C046318:dopexamine; D004298:Dopamine