Beta Antagonists and Vasodilators Flashcards

1
Q

Esmolol Class

A

selective B1 antagonist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Esmolol Use

A

used to prevent or minimize tachycardia and hypertension in response to perioperative stimuli (such as intubation, surgical stimulation, and emergence)
May decrease post op opioid requirements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Esmolol MOA

A

Competitive antagonist of B1 receptors (inhibits B2 receptors at higher doses)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Esmolol Dose

A

0.5mg/kg or 10mg
Infusion = 50 mcg/kg/min
(Uptitrate q5min to max dose 200 mcg/kg/min)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Esmolol Pharmacokinetics

A
Onset = 1 - 2 min 
DOA = 5 - 10 min 
Metabolism = rapid hydrolysis by plasma esterase metabolism in RBCs 
Elimination = renal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Esmolol Contraindications

A

Bradycardia, 1st degree heart block, cardiac failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Esmolol Considerations

A

Caution in patients with hypotension and bronchoconstriction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Labetolol Class

A

Non-selective alpha and beta antagonist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Labetolol Use

A

treat tachycardia and hypertension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Labetolol MOA

A

competitive antagonist of B1, B2, and A1 receptors

Beta blockade to alpha blockade is 7:1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Labetolol Dose

A

Intermittent bolus 5 - 20 mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Labetolol Pharmacokinetics

A
Onset = 5 min 
DOA = 3 - 6 hours 
Metabolism = hepatic 
Elimination = hepatic and renal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Labetolol Contraindications

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Labetolol Considerations

A

May cause left ventricular failure, orthostatic hypotension, and bronchospasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Nitroglycerin Class

A

Peripheral vasodilator, venous dilation predominating over arterial dilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Nitroglycerin Use

A

Relieves myocardial ischemia, coronary vasospasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Nitroglycerin MOA

A

Comes from it’s metabolism
As NTP is metabolized, it released nitric oxide + cyanide
NO activates guanylyl cyclase, which synthesize cGMP, decreases intracellular calcium, causing SM dilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Nitroglycerin Dose

A

IV Infusion: 5 - 100 mcg/min

SL: 0.4 mg

19
Q

Nitroglycerin Pharmacokinetics

A

Onset: 2 - 5 minutes
DOA: 5 - 10 minutes
Metabolism: rapid reductive hydrolysis in liver + blood by glutathione-organic nitrate reductase
Produces nitrate, which can convert hemoglobin to methemoglobin
Elimination: Kidneys

20
Q

Nitroglycerin Contraindications

A

Caution: AS, hypertrophic cardiomyopathy, increased ICP, hypotension, CHF

21
Q

Nitroglycerin Considerations

A

Risk for methemoglobinemia
Tolerance may develop with prolonged use
Side effects: headache, tachycardia (rebound from dilated veins)
Ideal for MIs: decreasing preload reduces myocardial oxygen demand & increases endocardial perfusion
Redistributes coronary BF to ischemic areas of subendocardium
Relieves coronary vasospasm

22
Q

Nitroprusside Class

A

Direct peripheral arterial vasodilator, non-selective relaxation of arterial & venous SM

23
Q

Nitroprusside Use

A

Reliable & easily-titrated antihypertensive

24
Q

Nitroprusside MOA

A

As NTP is metabolized, it releases nitric acid + cyanide

NO activates guanylyl cyclase which synthesizes cGMP, decreases intracellular calcium, causing SM dilation

25
Q

Nitroprusside Dose

A

Infusion: 0.3 - 10 mcg/kg/min

26
Q

Nitroprusside Pharmacokinetics

A

Onset: 1 minute
DOA: 3 - 5 minutes
Metabolism: into cyanide then to thiocyanate, which then is eliminated by kidneys
Elimination: Thiocyanate cleared by kidneys

27
Q

Nitroprusside Contraindications

A

Caution in patients w/ AS, hypertrophic cardiomyopathy, increased ICP, hypotension, heart failure
Renal failure due to buildup of thiocyanate causing thyroid dysfunction, muscle weakness, nausea, hypoxia, acute toxic psychosis

28
Q

Nitroprusside Considerations

A

Side effects: headache, tachycardia, bronchodilation (due to NO)
Dilation of coronary arterioles may result in an intracoronary steal
Reductions in pulmonary artery pressure & the hypoxic pulmonary vasoconstriction mechanism may decrease lung perfusion
Large doses of NTP may lead to methemoglobinemia
Risk of cyanide toxicity

29
Q

Nitroprusside Considerations

A

Side effects: headache, tachycardia, bronchodilation (due to NO)
Dilation of coronary arterioles may result in an intracoronary steal
Reductions in pulmonary artery pressure & the hypoxic pulmonary vasoconstriction mechanism may decrease lung perfusion
Large doses of NTP may lead to methemoglobinemia
Risk of cyanide toxicity

30
Q

Hydralazine Class

A

Direct acting arterial vasodilator

31
Q

Hydralazine Use

A

Hypertension

32
Q

Hydralazine MOA

A

Activate guanylate cyclase to increase cGMP

33
Q

Hydralazine Dose

A

Intermittent boluses: 2.5 - 20 mg

34
Q

Hydralazine Pharmacokinetics

A

Onset: 15 minutes
DOA: 2 - 4 hours
Metabolism: Liver
Elimination: Kidneys

35
Q

Hydralazine Contraindications

A

Caution in patients who cannot tolerate reflex tachycardia or hypotension (CAD, AS, hypertrophic cardiomyopathy, increased ICP, CHF)

36
Q

Hydralazine Considerations

A

Reflex tachycardia, hypotension

37
Q

Nicardipine Class

A

Calcium channel blocker

38
Q

Nicardipine Use

A

Angina, HTN, arrhythmias, peripheral vascular disease, esophageal spasm, cerebral vasospasm, & controlled hypotension

39
Q

Nicardipine MOA

A
  • Depress electrical impulses in the sinoatrial (SA) + atrioventricular (AV) nodes by blocking the influx of Ca, resulting in negative chronotropic + inotropic effects & increasing coronary + systemic vasodilation – specifically L-type Ca channels
  • Blocks calcium influx into vascular smooth muscle and cardiac muscle
40
Q

Nicardipine Dose

A

5 mg/hr, increase by 2.5 mg/hr every 15 minutes, up to 15 mg/hr

41
Q

Nicardipine Pharmacokinetics

A

Onset: 1 - 5 minutes
DOA: 3 - 6 hours
Metabolism: Liver
Elimination: Kidneys

42
Q

Nicardipine Contraindications

A

Caution in acute MI, HF, bradycardia, hypotension, dantrolene (both work on Ca channels)

43
Q

Nicardipine Considerations

A

Reflex tachycardia, headache