Beta Antagonists Flashcards
Labetalol Class
Non-selective beta antagonist
Labetalol MOA (3)
Competitive antagonist of β1, β2 and α1 receptors
Decreases SVR. BP, and HR
β-blockade: α-blockade ratio is 7:1
Labetalol Use (2)
Used to treat tachycardia and hypertension
Labetalol Dosing
Intermittent boluses: 5 – 20 mg
Labetalol Onset and DOA
Onset: 5 minutes
DOA: 3-6 hours
Labetalol Metabolism
Liver
Labetalol Excretion
Liver and Kidneys
Labetalol Admin Considerations (3)
Caution in patients with bradycardia, hypotension, CHF, asthma and COPD
May cause left ventricular failure, orthostatic hypotension, and bronchospasm
No reflex tachycardia
Esmolol Class
Selective β1 antagonist
Class II antiarrhythmic
Esmolol MOA
Competitive antagonist of β1 receptors (inhibit β2 receptors at higher doses)
Slows conduction of AV node -> decreases HR & BP
Esmolol Uses (2)
Used to prevent or minimize tachycardia and hypertension in response to perioperative stimuli, such as intubation, surgical stimulation, and emergence
May decrease post operative opioid requirements
Esmolol Dosing
Bolus: 0.5 mg/kg or 10 mg
Infusion: 50-300 mcg/kg/min)
Esmolol Onset and DOA
Onset: 1 minutes
DOA: 5-10 minutes
Esmolol Metabolism
Rapid hydrolysis by plasma esterase metabolism in RBCs
Esmolol Excretion
Kidneys