Liberal Versus Restrictive Use of Dobutamine in Cardiac Surgery (DOBUTACS)

Liberal Versus Restrictive Dobutamine in Cardiac Surgery (DOBUTACS): a Prospective Randomized Non-inferiority Clinical Trial

Inotropic agents are usually administered in the postoperative period after cardiac surgery. In most cases, dobutamine is administered routinely, for the probable occurrence of myocardial dysfunction after cardiopulmonary bypass or a low cardiac output with minimal evidence of altered tissue perfusion. Recent data show that inotropic agents are used in 35-52% of cardiac surgeries in the perioperative period. However, the use of inotropic agents may be associated with adverse events, including myocardial ischemia, by elevation in myocardial oxygen consumption and the imbalance between supply and consumption, and tachyarrhythmias (atrial fibrillation, sinus tachycardia, ventricular tachyarrhythmias), primarily due to the β1-adrenergic effect. This study is a non-inferiority clinical randomized study aiming to compare the use of dobutamine in a liberal strategy (in all patients at the time of withdrawal of CPB) with a restrictive strategy (based on clinical and hemodynamic evidence of low cardiac output syndrome associated with altered tissue perfusion). Our primary hypothesis is that the restrictive use of dobutamine is as safe and effective as the liberal one.

Patients will receive dobutamine during the first 8 hours after cardiopulmonary bypass weaning only if they have a cardiac index of ≤ 2.5L/min/m2 and at least one sign of tissue hypoperfusion: ScvO2 ≤ 70% and / or urine output < 2 mL/Kg/h despite adequate fluid replacement.

Combined endpoint of arrhythmias (ventricular and supraventricular), acute myocardial infarction, stroke or transient ischemic attack, low-output syndrome, cardiogenic shock and death from all causes within 30 days after cardiac surgery

We will compare the incidence of acute myocardial infarction between groups within 30 days after randomization

We will compare the incidence of low cardiac output syndrome between groups within 30 days after randomization

We will compare the incidence of ventricular and supraventricular arrhythmias between groups within 30 days after randomization

We will compare the number of days free of mechanical ventilation between groups within 30 days after randomization

We will compare the incidence of severe sepsis and septic shock between groups within 30 days after randomization

Inclusion Criteria: Patients undergoing cardiac surgery of coronary artery bypass graft (CABG) with cardiopulmonary bypass; Age equal or greater than 18 years; Written informed consent. Exclusion Criteria: Previous ventricular dysfunction (ejection fraction lower than 50%) Sustained supraventricular or ventricular arrhythmias; Cardiogenic shock or need for inotropes before surgery; Immediate need of ventricular assist device or intraaortic balloon after CPB; Combined procedure; Pregnancy; Participation in another study.

Franco RA, de Almeida JP, Landoni G, Scheeren TWL, Galas FRBG, Fukushima JT, Zefferino S, Nardelli P, de Albuquerque Piccioni M, Arita ECTC, Park CHL, Cunha LCC, de Oliveira GQ, Costa IBSDS, Kalil Filho R, Jatene FB, Hajjar LA. Dobutamine-sparing versus dobutamine-to-all strategy in cardiac surgery: a randomized noninferiority trial. Ann Intensive Care. 2021 Jan 26;11(1):15. doi: 10.1186/s13613-021-00808-6.