Hypertension Overview and Blood Pressure Levels

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Questions and Answers

What is a notable adverse effect associated with high dosages of hydralazine?

Hyperglycemia

Bronchospasm

Lupus-like syndrome (correct)

Severe hypotension

Which therapeutic action does minoxidil primarily perform?

Dilates veins

Dilates arterioles (correct)

Inhibits beta-adrenergic receptors

Increases potassium retention

What is recommended to mitigate the side effects associated with minoxidil?

Limit potassium intake

Co-administer with a beta blocker and diuretic (correct)

Increase fluid intake

Use in isolation

Which of the following is NOT a common adverse effect of hydralazine?

Edema Signup and view all the answers

What effect does the active metabolite of minoxidil have on smooth muscle membranes?

Opens potassium channels Signup and view all the answers

What are some common risk factors for hypertension?

Increased salt intake Signup and view all the answers

Which of the following is a distinguishing feature of essential hypertension?

It is often polygenic with multiple contributing factors. Signup and view all the answers

What is the normal range for blood pressure in adults?

90–120/60–80 mm Hg Signup and view all the answers

What role does peripheral vascular resistance play in blood pressure regulation?

It is directly proportional to blood pressure. Signup and view all the answers

Which of the following is an example of secondary hypertension?

Hypertension linked to renal disease Signup and view all the answers

How does smoking cessation affect hypertension?

It decreases concurrent cardiovascular risk. Signup and view all the answers

Which component is NOT usually associated with the pathophysiology of hypertension?

Decreased peripheral resistance Signup and view all the answers

Which lifestyle modification can help reduce blood pressure?

Reducing alcohol consumption Signup and view all the answers

What is the primary mechanism of action of fenoldopam?

Agonist of dopamine D1 receptors Signup and view all the answers

Which of the following conditions should fenoldopam be avoided in?

Glaucoma Signup and view all the answers

What effect do calcium channel blockers have on peripheral resistance and blood pressure?

Decrease peripheral resistance and decrease blood pressure Signup and view all the answers

Which of the following is NOT a major toxicity associated with fenoldopam?

Decreased renal function Signup and view all the answers

Which calcium channel blocker is specifically formulated for intravenous use?

Clevidipine Signup and view all the answers

What is the primary reason for the discontinuation of ganglion blocking agents in hypertension therapy?

Excessive orthostatic hypotension and sexual dysfunction Signup and view all the answers

What potential effect can occur with sudden withdrawal of clonidine?

Hypertensive crisis Signup and view all the answers

Which of the following describes the mechanism of action of reserpine?

Interferes with biogenic amine storage Signup and view all the answers

Which effect is NOT associated with the use of tricyclic antidepressants in conjunction with clonidine?

Enhance clonidine effectiveness Signup and view all the answers

Which of the following represents a significant toxicity of guanethidine?

Profound sympathoplegia Signup and view all the answers

What characterizes the action of adrenergic neuron blocking agents?

Inhibit norepinephrine release Signup and view all the answers

Which adverse effect is commonly associated with ganglion blocking agents?

Dry mouth Signup and view all the answers

In what way does reserpine primarily lower blood pressure?

Decreases cardiac output and peripheral vascular resistance Signup and view all the answers

What is the primary clinical use of esmolol?

Management of intra-operative and post-operative hypertension Signup and view all the answers

Which statement best describes the mechanism of action of α1 blockers?

They block α1 receptors, causing vasodilation in arterioles and venules. Signup and view all the answers

What is a significant risk associated with the first dose of α1 blockers?

Postural hypotension Signup and view all the answers

How does esmolol's short half-life affect its clinical use?

It allows for quick discontinuation if adverse effects occur. Signup and view all the answers

Which of the following conditions does not benefit from α1 blocker treatment?

Chronic heart failure Signup and view all the answers

What is one major reason for combining α1 blockers with a diuretic?

To prevent water retention associated with α1 blockers. Signup and view all the answers

What effect does norepinephrine have when α1 receptors are blocked?

Negative feedback on its own release Signup and view all the answers

What is the half-life of terazosin, and how does it compare to doxazosin?

12 hours, shorter than doxazosin (22 hours) Signup and view all the answers

Study Notes

Hypertension

Definition: Persistent high arterial blood pressure (HT) that can lead to damage in blood vessels of the kidney, heart, and brain.
Risks: Genetic factors, psychological stress, environmental factors (increased salt intake and decreased potassium or calcium intake), alcohol consumption, and obesity.
Additional Risk Factors: Established cardiovascular disease (angina, previous stroke or myocardial infarction), established target organ damage, smoking, hyperlipidemia and diabetes.
Diagnosis: Repeated measurements of elevated blood pressure.
Lifestyle Modifications: Healthy diet (moderation of alcohol and salt intake), exercise, smoking cessation, and medication.

Blood Pressure In Adults

Low Blood Pressure: 70-90/40-60 mmHg
Normal Blood Pressure: 90-120/60-80 mmHg
Elevated Blood Pressure: 120-129/80 mmHg
Stage I Hypertension: 130-139/80-90 mmHg
Stage II Hypertension: >140/>90 mmHg

Regulation Of Normal Blood Pressure

Blood Pressure is directly proportional to the product of the blood flow (cardiac output) and the resistance to blood flow in arterioles (peripheral vascular resistance).
BP = CO x PVR

Postural Baroreflex

Baroreflexes are responsible for rapid adjustments in blood pressure.

Hydralazine

A vasodilator used in the treatment of hypertension.
Mechanism of Action: Relaxes vascular smooth muscle.
Adverse Effects: Most common side effects include headache, nausea, anorexia, palpitations, sweating, and flushing.
Uncommon Adverse Effects: Peripheral neuropathy and drug fever.

Minoxidil

Orally active vasodilator used in the treatment of hypertension.
Mechanism of Action: Opens potassium channels in smooth muscle membranes, resulting in dilation of arterioles.
Adverse Effects: Tachycardia, palpitations, angina, edema, headache, sweating, and hypertrichosis.

Diazoxide

A vasodilator used in the treatment of hypertensive emergencies and hypoglycemia caused by hyperinsulinism.
Mechanism of Action: Opens potassium channels in smooth muscle membranes, resulting in dilation of arterioles.
Adverse Effects: Can cause excessive hypotension, reflex sympathetic response, and hyperglycemia.

Fenoldopam

A peripheral arteriolar dilator used for hypertensive emergencies, postoperative HT.
Mechanism of Action: Agonist of dopamine D1 receptors, resulting in dilation of peripheral arteries and natriuresis.
Adverse Effects: Reflex tachycardia, headache, and flushing.
Contraindication: Avoid in patients with glaucoma.

Calcium Channel Blockers

Used to treat hypertension, angina, and arrhythmias.
Mechanism of Action: Inhibit calcium influx into arterial smooth muscle cells, resulting in vasodilation.
Types: Verapamil, diltiazem, and the dihydropyridine family (amlodipine, felodipine, isradipine, nicardipine, nifedipine, nisoldipine, nimodipine, and nitrendipine).
Adverse Effects: Can cause bradycardia, hypotension, headache, and edema.

Clonidine

A centrally-acting alpha2-adrenergic agonist used in the treatment of hypertension.
Mechanism of Action: Decreases sympathetic outflow from the central nervous system, resulting in decreased heart rate and peripheral vascular resistance.
Adverse Effects: Drowsiness, dry mouth, and constipation.
Contraindication: Concomitant treatment with tricyclic antidepressants may block the antihypertensive effect of clonidine.

Ganglion Blocking Agents

Historically among the first agents used in the treatment of hypertension.
Mechanism of Action: Block nicotinic cholinoceptors on postganglionic neurons.
Adverse Effects: Sympathoplegia (orthostatic hypotension and sexual dysfunction) and parasympathoplegia (constipation, urinary retention, glaucoma, blurred vision, and dry mouth).

Adrenergic Neuron Blocking Agents

Lower blood pressure by preventing the release of norepinephrine from postganglionic sympathetic neurons.
Types: Guanethidine, Guanadrel, Bethanidine, and Debrisoquin.
Adverse Effects: Profound sympathoplegia (marked postural hypotension, diarrhea, and impaired ejaculation).

Reserpine

An alkaloid extracted from the roots of an Indian plant, Rauwolfia serpentine.
Mechanism of Action: Blocks the ability of aminergic transmitter vesicles to take up and store biogenic amines, resulting in depletion of norepinephrine, dopamine, and serotonin in central and peripheral neurons.
Adverse Effects: Can cause depression, sedation, and orthostatic hypotension.

Esmolol

A beta1-selective adrenergic antagonist used in the treatment of hypertension.
Mechanism of Action: Blocks beta1-adrenoceptors in the heart, decreasing heart rate and contractility.
Adverse Effects: Can cause bradycardia and hypotension.

Alpha-1 Blockers

Selectively block alpha1-receptors in arterioles and venules, resulting in vasodilation.
Types: Prazosin, terazosin, and doxazosin.
Adverse Effects: Can cause orthostatic hypotension, dizziness, and headache.

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Description

This quiz covers the definition of hypertension, its risk factors, and the classification of blood pressure levels in adults. Explore lifestyle modifications and diagnostic criteria important for managing this condition.