Doubts raised over dopamine safety for shock
MedWire News: Dopamine is associated with more arrhythmias than is norepinephrine in patients with shock, and increases mortality in those with cardiogenic shock, shows a randomized trial.
“This study raises serious concerns about the safety of dopamine therapy,” say Daniel De Backer (Erasme University Hospital, Brussels, Belgium) and colleagues in the New England Journal of Medicine.
The team randomly assigned 1679 patients with shock (62.2% septic, 16.7% cardiogenic, 15.7% hypovolemic) to receive dopamine 20 µg/kg/minute or norepinephrine 0.19 µg/kg/minute as first-line therapy to restore and maintain blood pressure.
At 28 days, mortality rates were not significantly different between the groups, at 52.5% and 48.5% in the dopamine and norepinephrine groups, respectively.
But 24.1% of dopamine-treated patients developed arrhythmias (most commonly atrial fibrillation), compared with just 12.4% of those given norepinephrine. Severe arrhythmias forced withdrawal of the study drug in 6.1% of the dopamine group compared with 1.6% of the norepinephrine group.
Through day 28, dopamine-treated patients had significantly fewer days where they did not need the study drug than those in the norepinephrine group, at 11.0 versus 12.5, and where they did not require open-label vasopressors, at 21.6 versus 14.2.
There were 280 patients with cardiogenic shock in the study. Among this subgroup, mortality was significantly more likely with dopamine than with norepinephrine, report the researchers.
“The exact cause of the increased mortality cannot be determined, but the early difference in the rate of death suggests that the higher heart rate with dopamine may have contributed to the occurrence of ischemic events,” they say.
“Whatever the mechanism may be, these data strongly challenge the current American College of Cardiology–American Heart Association guidelines, which recommend dopamine as the first-choice agent to increase arterial pressure among patients who have hypotension as a result of an acute myocardial infarction.”
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By Eleanor McDermid