Beta Antagonists

Question 1

Labetalol Class

Answer 1

Non-selective beta antagonist

Question 2

Labetalol MOA (3)

Answer 2

Competitive antagonist of β1, β2 and α1 receptors

Decreases SVR. BP, and HR

β-blockade: α-blockade ratio is 7:1

Question 3

Labetalol Use (2)

Answer 3

Used to treat tachycardia and hypertension

Question 4

Labetalol Dosing

Answer 4

Intermittent boluses: 5 – 20 mg

Question 5

Labetalol Onset and DOA

Answer 5

Onset: 5 minutes
DOA: 3-6 hours

Question 6

Labetalol Metabolism

Answer 6

Liver

Question 7

Labetalol Excretion

Answer 7

Liver and Kidneys

Question 8

Labetalol Admin Considerations (3)

Answer 8

Caution in patients with bradycardia, hypotension, CHF, asthma and COPD

May cause left ventricular failure, orthostatic hypotension, and bronchospasm

No reflex tachycardia

Question 9

Esmolol Class

Answer 9

Selective β1 antagonist

Class II antiarrhythmic

Question 10

Esmolol MOA

Answer 10

Competitive antagonist of β1 receptors (inhibit β2 receptors at higher doses)

Slows conduction of AV node -> decreases HR & BP

Question 11

Esmolol Uses (2)

Answer 11

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

Question 12

Esmolol Dosing

Answer 12

Bolus: 0.5 mg/kg or 10 mg

Infusion: 50-300 mcg/kg/min)

Question 13

Esmolol Onset and DOA

Answer 13

Onset: 1 minutes
DOA: 5-10 minutes

Question 14

Esmolol Metabolism

Answer 14

Rapid hydrolysis by plasma esterase metabolism in RBCs

Question 15

Esmolol Excretion

Answer 15

Kidneys

Question 16

Esmolol Admin Consideration

Answer 16

Caution in patients with bradycardia, hypotension, CHF, bronchoconstriction, and high degree AVB