phenylephrine
Pronunciation: fen-il-EF-rin
An alpha-1 adrenergic agonist vasopressor commonly used to treat hypotension during cardiac anesthesia.
Full Definition
Phenylephrine is a selective alpha-1 adrenergic receptor agonist that causes vasoconstriction and increases systemic vascular resistance. In cardiothoracic anesthesia, it is frequently used to manage hypotension, particularly in patients with preserved cardiac function where increased afterload is tolerated. Unlike epinephrine or norepinephrine, phenylephrine lacks significant beta-adrenergic activity, making it useful when pure vasoconstriction is desired without increased heart rate or contractility. The drug can be administered as bolus doses or continuous infusion, and proper dosing terminology is critical in anesthetic records.
Usage
Usage note: Ensure correct spelling; often confused with other 'phen-' prefix medications.
In Context
- "Phenylephrine 100 mcg was administered to treat post-induction hypotension." — anesthetic record
- "A phenylephrine infusion at 0.5 mcg/kg/min maintained adequate perfusion pressure." — clinical note