In this episode, I’ll discuss whether to use phentolamine to treat dobutamine extravasation.
Extravasation of vasopressors is of great concern due to vasoconstriction and tissue necrosis at the site of extravasation. Since the vasoconstriction is due to alpha1-adrenergic agonism, phentolamine works as a direct antidote to extravasation by blocking alpha1 receptors.
Dobutamine is used clinically as an inotrope, not a vasopressor, leading clinicians to question whether extravasation from dobutamine should be treated with phentolamine. Despite being classified as an inotrope, the L-isomer of dobutamine has alpha1-adrenergic effects.
There is a case report of dermal necrosis from dobutamine extravasation. In this report, the authors did not give phentolamine only because of the time that had lapsed between when the extravasation happened and when it was recognized. For dobutamine extravasation that is caught early and before necrosis occurs, I prefer to use phentolamine in the same manner as I would for a vasopressor extravasation.
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