Adjuncts

Question 1

B1 selective medications

Answer 1

Metoprolol, atenolol, esmolol

B1 and B2

Question 2

1/2 life of propranolol
Dose?

Answer 2

2-3 hours
1-10mg IV

Question 3

1/2 life of metoprolol
Dose?

Answer 3

3-4 hours
1-15mg IV

Question 4

1/2 life of atenolol

Answer 4

6-7 hours
5-10mg

Question 5

1/2 life of esmolol

Answer 5

0.15 hr (<9 min)
10-80mg IV
(Typically 20-30mg IV)

Question 6

Why choose labetalol over selective β1-blockers (e.g., esmolol, metoprolol)

Answer 6

Avoid reflex tachycardia

Pure β1-blockers ↓ HR and contractility, but can sometimes trigger reflex vasoconstriction.
Labetalol’s α1-blockade causes vasodilation, so BP drops without reflex tachycardia.

More balanced BP control
For perioperative hypertension or aortic dissection, you want both ↓ HR (β1) and ↓ afterload (α1).

Useful in catecholamine surges
In pheochromocytoma, thyroid storm, or peri-intubation, you get combined α1- and β-blockade, reducing both BP and HR spikes.

Esmolol / other selective β-blockers
Only lower HR and contractility (β1), minimal effect on peripheral resistance.
BP may drop less effectively unless you add a vasodilator.

**
Labetalol adds α1-blockade → vasodilation → ↓ afterload. The advantage is:

BP reduction is stronger than with a β1-blocker alone, because selective β-blockers mostly decrease HR and contractility, not peripheral resistance.

Reflex tachycardia is already blunted by β1-blockade, but labetalol also lowers BP more effectively without needing a second drug.

**
When β1-selective is preferred

Asthmatics or severe COPD → avoid β2 blockade
Isolated tachycardia with modest BP elevation → esmolol is short-acting and titratable
Situations where vasodilation is risky → avoid labetalol

Question 7

Dihydropyrimidines

Answer 7

Nicardipine (cardene)
*drop BP but still maintaining coronary perfusion/greatest coronary artery dilation)

Decrease vascular smooth muscle contractility (peripheral vasodilation)

Binds to receptors on voltage-gated calcium ion channels (L-type; main pathway)

Question 8

Benzothiazepines

Answer 8

Diltiazem

Decreased speed of conduction through AV node

Binds to receptors on voltage-gated calcium ion channels (L-type; main pathway)

Question 9

Phenylalkylamines

Answer 9

Verapamil

Decreased speed of conduction through AV node

Binds to receptors on voltage-gated calcium ion channels (L-type; main pathway)

Question 10

Nitro dose

Answer 10

5-10mcg/min
tachyphylaxis

Question 11

Sodium nitroprusside dose

Answer 11

0.3mcg/kg/min
titrated to 2mcg/kg/min

S/E Cyanide poisoning (upon contact w/ oxyhgb CN/NO)
Tx: Methylene blue

Question 12

Hydralizine dose
1/2 time
Onset
Peak

Answer 12

5mg (20mg/ml)
1/2 time is 3-7 hours
Onset: Slow
Peak: 1 hour

Question 13

Preferred sympathomimetic for pregnancy

Answer 13

Ephedrine (no effect on uterine blood flow)

Question 14

useful during abdominal surgeries

Answer 14

lidocaine

Question 15

alpha-2 receptors are highest where?

Answer 15

Locus coeruleus (brainstem)

Question 16

Does neostigmine cause n/v?

Answer 16

yes give with atropine instead of glycopyrolate

succ better

Question 17

ctz?

Answer 17

area postrema

no bbb

Question 18

Aprepitant (Emend)
Dose:
When to give:

Answer 18

40 to 125mg
2-3 hours prior to induction

greater anti vomiting than anti nausea