Dobutamine-sparing versus dobutamine-to-all strategy in cardiac surgery: a randomized noninferiority trial

Background: The detrimental effects of inotropes are well-known, and in many fields they are only used within a goal-directed therapy approach. Nevertheless, standard management in many centers includes administering inotropes to all patients undergoing cardiac surgery to prevent low cardiac output syndrome and its implications. Randomized evidence in favor of a patient-tailored, inotrope-sparing approach is still lacking. We designed a randomized controlled noninferiority trial in patients undergoing cardiac surgery with normal ejection fraction to assess whether an dobutamine-sparing strategy (in which the use of dobutamine was guided by hemodynamic evidence of low cardiac output associated with signs of inadequate tissue perfusion) was noninferior to an inotrope-to-all strategy (in which all patients received dobutamine). Results: A total of 160 patients were randomized to the dobutamine-sparing strategy (80 patients) or to the dobutamine-to-all approach (80 patients). The primary composite endpoint of 30-day mortality or occurrence of major cardiovascular complications (arrhythmias, acute myocardial infarction, low cardiac output syndrome and stroke or transient ischemic attack) occurred in 25/80 (31%) patients of the dobutamine-sparing group (p = 0.74) and 27/80 (34%) of the dobutamine-to-all group. There were no significant differences between groups regarding the incidence of acute kidney injury, prolonged mechanical ventilation, intensive care unit or hospital length of stay. Discussion: Although it is common practice in many centers to administer inotropes to all patients undergoing cardiac surgery, a dobutamine-sparing strategy did not result in an increase of mortality or occurrence of major cardiovascular events when compared to a dobutamine-to-all strategy. Further research is needed to assess if reducing the administration of inotropes can improve outcomes in cardiac surgery. Trial registration ClinicalTrials.gov, NCT02361801. Registered Feb 2nd, 2015. https://clinicaltrials.gov/ct2/show/NCT02361801.