Module 02: Drugs for the Cardiovascular System-Part 1

Module 03: Drugs for the Cardiovascular System-Part 2

Fall 2025

Objectives

• By the end of this module, you will be able to:
• Compare the various classes of medications used to treat disorders related to the cardiovascular system.
• Identify the indications, pharmacokinetics, laboratory monitoring, and side effects of medications used to treat disorders of the cardiovascular system.
• Describe evidence-based nursing practice for the care of clients taking medications that affect the cardiovascular system.

Chapter 34 Antihypertensive Drugs

Blood Pressure and Hypertension

• Blood pressure: force of blood against artery walls; normal is considered 120/80 mm Hg or lower
• Hypertension: high blood pressure that stays elevated over time; blood pressure of 130/90 mm Hg or higher
• Prehypertension: elevated blood pressure; at risk of developing hypertension; occurs when the systolic blood pressure falls between 120 and 129 mm Hg and the diastolic blood pressure remains between 80 and 89 mm Hg.

Normal and Abnormal Blood Pressure Levels in Adults

Risk Factors for Hypertension

• Weight loss (if the client is overweight)
• Stress reduction (e.g., relaxation techniques, meditation, and yoga)
• Regular aerobic exercise
• Smoking cessation (if applicable)
• Moderation of alcohol consumption
• Dietary changes, such as a decrease in sodium (salt) intake

Nonpharmacologic Treatment of Hypertension

Drugs Used to Treat Hypertension

Like furosemide and hydrochlorothiazide

Diuretics

Like atenolol and propranolol

ẞ-Adrenergic blocking drugs

Antiadrenergic drugs (centrally acting)

Like clonidine and methyldopa

Antiadrenergic drugs (peripherally acting)

Like doxazosin and prazosin

Calcium channel blocking drugs

Like amlodipine and diltiazem

Angiotensin-converting enzyme inhibitors (ACEIs)

Like captopril and enalapril

Angiotensin II receptor antagonists

Like irbesartan and losartan

Like hydralazine and minoxidil

Vasodilating drugs

Like aliskiren

Direct renin inhibitors

Selective aldosterone receptor antagonists

Like eplerenone

Antihypertensive Drugs—Actions

Drugs with vasodilating properties (adrenergic blocking and calcium-channel blocking)

• creates an in creases in the lumen of the arterial blood vessels, thus increasing the space available for blood to circulate and decreasing blood pressure

Diuretics:

• increase the excretion of sodium

Angiotensin-converting enzyme inhibitors (ACEIs):

• inhibit the activity of ACE, which converts angiotensin I to angiotensin II and causes vasoconstriction and secretion of aldosterone (retention of sodium and water); prevention of this process means that sodium and water are not retained and blood pressure decreases

Calcium channel blockers:

• inhibit the movement of calcium ions across the cell membranes of cardiac and arterial muscle cells; results in less calcium available for the transmission of nerve impulses and blood vessels relax; increases the supply of oxygen to the heart and reduces the heart’s workload

Angiotensin II receptor antagonists:

• block the binding of angiotensin II at various receptor sites in the vascular smooth muscle and adrenal gland; blocks the vasoconstrictive effect of the renin-angiotensin system and release of aldosterone; results in lowering blood pressure

Antihypertensive Drugs—Uses

• Used in the treatment of hypertension and heart failure
• Different types of hypertensives are often prescribed to be taken together if the client’s hypertension does not respond to just one drug therapy
• Nitroprusside is used via IV to treat hypertensive emergencies

Antihypertensive Drugs—Adverse Reactions

• Central Nervous System Reactions:
• Fatigue
• Depression
• Dizziness
• Headache
• Syncope

Antihypertensive Drugs—Adverse Reactions

• Respiratory System Reactions:
• Upper respiratory infections
• Cough

Antihypertensive Drugs—Adverse Reactions

• Gastrointestinal System Reactions:
• Abdominal pain
• Nausea
• Diarrhea
• Constipation
• Gastric irritation
• Anorexia

Antihypertensive Drugs—Adverse Reactions

• Other Reactions:
• Rash
• Pruritis
• Dry mouth
• Tachycardia
• Hypotension
• Proteinuria
• Neutropenia
• Orthostatic hypotension

Antihypertensive Drugs—Contraindications

• Contraindications:
• known hypersensitivity to the drugs
• ACEIs and angiotensin II receptor blockers: impaired renal function, salt or volume depletion, bilateral stenosis, angioedema, pregnancy (pregnancy category C), and lactation
• Calcium channel blockers: sick sinus syndrome, second- or third-degree heart block, hypotension, ventricular dysfunction, and cardiogenic shock

Antihypertensive Drugs—Precautions

• Use cautiously in clients with:
• Renal or hepatic impairment
• Electrolyte imbalances
• Lactation and pregnancy

Antihypertensive Drugs—Precautions

• Calcium-channel blockers: heart failure, renal or hepatic impairment, pregnancy (pregnancy category C) and lactation
• ACEIs: sodium depletion, hypovolemia, coronary or cerebrovascular insufficiency, clients receiving diuretic therapy or dialysis
• Angiotensin II receptor antagonists: renal or hepatic dysfunction, hypovolemia, volume or salt depletion, and in clients receiving high doses of diuretics

ACEi Drug—Interactions

ACEi Drug—Interactions

Calcium Channel Blockers—Interactions

Angiotensin II Receptor Antagonists—Interactions

Nursing Process—Client Receiving an Antihypertensive Drug

• Preadministration Assessment
• Objective Data
• Vital signs
• Blood pressure readings in lying, sitting, and standing positions
• Weight
• Laboratory tests: lipid profile and pregnancy test

Nursing Process—Client Receiving an Antihypertensive Drug

• Preadministration Assessment (continued)
• Subjective Data
• Medical history of hypertension and modifiable factors
• Current list of all drugs and supplements

Nursing Process—Client Receiving an Antihypertensive Drug

• Ongoing Assessment
• Frequently monitor blood pressure and take blood pressure readings in same arm with client in the same position
• Blood pressure measurement before each administration of the drug
• Hold the drug if the blood pressure is significantly lower than baseline
• Menopausal women: use of birth control while on ACEIs and angiotensin II receptor antagonists
• Assess for edema and weight gain of more than 2 lbs or more per day

Nursing Process—Client Receiving an Antihypertensive Drug

• Nursing Diagnosis
• Dehydration related to excessive diuresis secondary to administration of a diuretic
• Injury Risk related to dizziness or lightheadedness secondary to postural or orthostatic hypotensive episodes
• Impaired Sexual Functioning related to impotence secondary to effects of antihypertensive drugs
• Activity Intolerance related to fatigue and weakness
• Acute Pain (acute headache) related to antihypertensive drugs

Nursing Process—Client Receiving an Antihypertensive Drug

• Planning
• Expected client outcomes depend on the reason for administration of the drug but include:
• Optimal response to therapy
• Blood pressure maintained in an acceptable range
• Management of adverse drug reactions
• Confidence in an understanding of the prescribed medication regimen

Nursing Process—Client Receiving an Antihypertensive Drug

• Implementation
• Promoting Optimal Response to Therapy—ACEIs
• ACEIs should be taken 1 hour before or 2 hours after meals
• The sustained-release capsules should not be crushed, opened or chewed
• Teach the client to refrain from using potassium-based salt substitutes (hyperkalemia)
• Support client if they develop a dry cough; report to primary health care provider
• If a significant drop in blood pressure occurs after the first dose, notify the provide

Nursing Process—Client Receiving an Antihypertensive Drug

Implementation

• Promoting Optimal Response to Therapy—Clonidine
• Clonidine transdermal patch:
• apply to hairless area of intact skin and keep in place for 7 days; select a different area of the body for each application
• reinforce loose patch with tape
• date and time the patch application and the date/time of the removal

Nursing Process—Client Receiving an Antihypertensive Drug

Implementation

• Promoting Optimal Response to Therapy—Other Antihypertensives
• Aliskiren: advise client to hold the drug if angioedema occurs and notify the primary health care provider
• Nitroprusside: for hypertensive emergency; continuous monitoring of blood pressure and cardiovascular status
• Most antihypertensive drugs can be given with or without food. If GI upset occurs, give with food.

Nursing Process—Client Receiving an Antihypertensive Drug

Implementation

• Monitoring and Managing Client Needs
• Dehydration
• Observe for dehydration and electrolyte imbalances
• Encourage client to drink oral fluids up to 2000 mL/day unless contraindicated
• Monitor for hyponatremia, hypokalemia, and other electrolyte imbalances

Nursing Process—Client Receiving an Antihypertensive Drug

Implementation

• Monitoring and Managing Client Needs
• Injury Risk
• If orthostatic hypotension occurs, teach client to rise slowly from laying to sitting to standing (1 to 2 minutes in each position) or to seek assistance getting out of a chair or bed

Nursing Process—Client Receiving an Antihypertensive Drug

Implementation

• Monitoring and Managing Client Needs
• Impaired Sexual Functioning
• Provide and open and understanding atmosphere to establish rapport and trust
• Allow client to express feelings
• Provide client educational literature in native language
• If sexual patterns are negatively affected, encourage other means of intimacy
• Encourage client to discuss the use of erectile dysfunction medications with provider

Nursing Process—Client Receiving an Antihypertensive Drug

Implementation

• Monitoring and Managing Client Needs
• Activity Intolerance
• Encourage client to walk and ambulate as they can tolerate and to gradually increase activity
• Teach client to plan rest periods
• Reassure client that fatigue diminishes after 4 to 6 weeks of therapy

Nursing Process—Client Receiving an Antihypertensive Drug

Implementation

• Monitoring and Managing Client Needs
• Acute Pain
• Client may develop a headache as an adverse effect
• Encourage client to remain in bed with a cool cloth on forehead and offer client back or neck rub
• Teach client to use guided imagery or progressive body relaxation
• Notify primary health care provider if nursing measures are not successful

Nursing Process—Client Receiving an Antihypertensive Drug

• Implementation—Educating the Client and Family
• Educate all clients that blood pressures should be checked periodically
• Emphasize the importance of drug therapy and following the therapeutic drug regimen
• Educate the client about the adverse reactions and to contact the primary health care provider if adverse reactions occur

Nursing Process—Client Receiving an Antihypertensive Drug

• Implementation—Educating the Client and Family (continued)
• Teach client to use blood pressure machine or community resources to measure blood pressure and to keep a blood pressure record
• Avoid the use of nonprescription drugs unless the primary health care provider is consulted
• Avoid alcohol and if the drug causes drowsiness, avoid driving or performing hazardous tasks

Nursing Process—Client Receiving an Antihypertensive Drug

• Implementation—Educating the Client and Family (continued)
• Teach client about diet restrictions and to avoid salt substitutes unless a particular brand is approved by the primary health care provider
• If client is at risk for orthostatic hypotension, teach client and family safety methods to prevent injury and falls at home

Nursing Process—Client Receiving an Antihypertensive Drug

• Evaluation
• Was the therapeutic effect achieved and was blood pressure controlled?
• Were adverse reactions: identified, reported, and managed?
• No evidence of dehydration
• No injury is evident
• Client is satisfied with sexual activity
• Client engages in activity as able
• Client is free of headache pain
• Did client and family express confidence and demonstrate understanding of drug regimen?

Osmotic diuretics

• Increase the density of the filtrate in the glomerulus
• Prevents the selective reabsorption of water
• Sodium and chloride excretion is also increased

Thiazide and related diuretics

• Inhibit reabsorption of sodium and chloride ions in the early distal tubule of nephron
• Results in excretion of sodium, chloride, and water
• Often the first drug used in the treatment of hypertension

Loop Diuretics

• Increase the reabsorption of sodium and chloride in the ascending portion of the loop of Henle
• Blocking the action of reabsorption in the portion of the nephron where a high percentage of sodium and fluid are usually reabsorbed is very effective

Carbonic anhydrase inhibitors

• Sulfonamides without bacteriostatic action that inhibit the enzyme carbonic anhydrase
• Results in the excretion of sodium, potassium, bicarbonate, and water

Potassium-sparing diuretics

• Works by blocking the reabsorption of sodium in the collecting tubules; increases sodium and water in the urine; reduces the excretion of potassium
• Spironolactone: antagonizes the action of aldosterone
• Aldosterone: enhances the reabsorption of sodium in the distal convoluted tubules of the kidney
• When aldosterone is inhibited, sodium (but not potassium) and water are excreted