Patho-Pharm: Ace Inhibitors, Beta-Blockers, Calcium Channel Blocks/ Vasodilators

ACE Inhibitors

Drugs that block ACE, the enzyme that makes angiotensin II, leading to vasodilation, lower blood volume, and reduced aldosterone activity

Hypertension

A condition characterized by consistently high blood pressure

Heart Failure

A chronic condition where the heart does not pump blood as well as it should

Kidney Protection

The use of medications to prevent kidney damage, particularly in patients with diabetes

Myocardial Infarction (MI)

A medical term for a heart attack, occurring when blood flow to the heart is blocked

Diabetic Retinopathy

A diabetes complication that affects the eyes, leading to vision impairment

First-dose Hypotension

A significant drop in blood pressure that can occur after the first dose of an ACE inhibitor

Dry, Nonproductive Cough

A common side effect of ACE inhibitors characterized by a persistent cough that does not produce mucus

Hyperkalemia

A condition where there is an elevated level of potassium in the blood, which can be a side effect of ACE inhibitors

Renal Failure

A medical condition in which the kidneys fail to adequately filter waste products from the blood

Fetal Injury

Potential harm to a developing fetus, particularly in the second and third trimesters, associated with ACE inhibitors

Angioedema

A severe allergic reaction that causes swelling of the face, throat, and other areas, which can occur with ACE inhibitors

Monitoring Blood Pressure

The process of regularly checking blood pressure levels to manage hypertension

Potassium Levels

The measurement of potassium in the blood, important for patients on ACE inhibitors due to the risk of hyperkalemia

Kidney Function

The assessment of how well the kidneys are working, crucial for patients taking ACE inhibitors

Adverse Effects

Negative reactions or side effects experienced by patients taking medications

Lithium Levels

The measurement of lithium in the blood, important for monitoring in patients taking ACE inhibitors

Bilateral Renal Artery Stenosis

A condition where both renal arteries are narrowed, contraindicating the use of ACE inhibitors

Pregnancy

A contraindication for ACE inhibitors due to the risk of fetal injury

History of Angioedema

A contraindication for ACE inhibitors, as previous episodes increase the risk of recurrence

Signs and Symptoms of Angioedema

Swelling of the face and throat region that requires immediate medical attention

Potassium Supplement Risks

The potential dangers of taking potassium supplements while on ACE inhibitors due to the risk of hyperkalemia

Contraindications of Diuretics

Conditions or factors that make the use of diuretics unsafe or inadvisable

Contraindications of NSAIDs

Conditions that make the use of non-steroidal anti-inflammatory drugs unsafe, particularly in conjunction with ACE inhibitors

First-generation beta-blockers

Block beta-1 and beta-2 receptors (e.g., propranolol)

Second-generation beta-blockers

Block beta-1 receptors only (e.g., metoprolol)

Third-generation beta-blockers

Act on blood vessels; may be nonselective or cardio selective (e.g., carvedilol)

Uses of beta-blockers

Angina, hypertension, dysrhythmias, MI, perioperative protection, and heart failure (e.g., carvedilol, bisoprolol, metoprolol)

Major side effects of beta-blockers

Rebound excitation, bradycardia, decreased cardiac output, worsening heart failure, AV block, bronchoconstriction, and inhibited glycogenolysis

Nursing considerations for beta-blockers

Monitor heart rate, blood sugar, breathing (for beta-2 blockers), and heart failure; obtain ECG; monitor fetus/newborn if used in pregnancy or breastfeeding

Contraindications for beta-blockers

Heart failure with low output, asthma (due to bronchoconstriction), diabetes, sinus bradycardia, AV block greater than first degree, patients on insulin, of those taking calcium channel blockers

Patient teaching for beta-blockers

Explain cardio selective vs nonselective beta-blockers, avoid nonselective agents in asthma/diabetes, and seek help with breathing problems or abnormal heart rates

Normal function of beta-adrenergic receptors

Stress hormones, epinephrine and norepinephrine, bind to beta-adrenergic receptors at normal rates, allowing the heart rate to be stable and stress on the heart to be minimal

Functional change in cardiovascular system

Can lead to hypertension, stroke, arrhythmias, or coronary artery disease due to overstimulation of beta-adrenergic receptors by epinephrine and norepinephrine

Cause of unstable angina

Can arise from coronary artery disease (buildup of plaque in arteries) and is often triggered by increased stress hormones

Major signs & symptoms of unstable angina

Dyspnea, diaphoresis, increased anxiety, and new chest pain

Complications of untreated cardiovascular disease

Often leads to heart failure, stroke, heart attacks, and possibly even death

Nursing priorities for beta-blockers

Airway, Breathing, Circulation (ABCs) → Assess → Intervene → Safety

Importance of monitoring in beta-blockers

Ensure the airway is clear, monitor breathing patterns and overall circulation, and watch for plaque buildup in the arteries

Action of calcium channel blockers

Block calcium entry leading to vasodilation, decreased heart contraction, decreased heart rate, and decreased AV conduction

Types of calcium channel blockers

Dihydropyridines (e.g., nifedipine) and non-dihydropyridines (e.g., verapamil, diltiazem)

Calcium Channel Blockers

Drugs that block calcium entry, leading to vasodilation, decreased heart contraction, decreased heart rate, and decreased AV conduction

Dihydropyridines

A type of calcium channel blocker, example includes nifedipine

Non-dihydropyridines

A type of calcium channel blocker, examples include verapamil and diltiazem

Major Side Effects of Verapamil

Constipation, edema, dizziness, bronchodilation, AV block

Interactions with Verapamil

Digoxin (increases AV block), beta-blockers (cardiac suppression), grapefruit juice (decreases metabolism, especially risky with nifedipine)

Major Side Effects of Nifedipine

Dizziness, edema, reflex tachycardia; does NOT cause heart failure, bradycardia, or AV block

Overdose of Nifedipine

Results in loss of selectivity

Major Side Effects of Alpha Blockers & Nitroglycerin

Orthostatic hypotension, reflex tachycardia

Nursing Considerations for Nifedipine

Monitor heart rate (reflex tachycardia), blood pressure (hypotension), heart failure, and AV block

Nursing Considerations for Verapamil

Monitor heart failure, liver impairment, digoxin/beta-blocker use

Nursing Considerations for Nitroglycerin

Monitor heart rate; stop long-acting forms slowly

Contraindications for Prazosin

Children should not take Prazosin

Contraindications for Verapamil

Avoided in patients with severe hypotension or 2nd/3rd-degree AV block

Contraindications for Nitroglycerin

Combining with sildenafil (Viagra) can lead to severe, potentially fatal hypotension

Patient Teaching for Nitroglycerin

Avoid alcohol; stand up slowly with alpha blockers/nitroglycerin

Patient Teaching for Calcium Channel Blockers

Limit grapefruit juice; recognize edema when taking CCBs

Patient Teaching for Nitroglycerin and Viagra

Never combine nitroglycerin with Viagra

Normal Function of Muscle Contraction

A nerve impulse releases ACh, creating an action potential that causes calcium release, leading to muscle contraction

Electrical Conduction in Heart

Starts in the SA node, moves to the AV node, then through the bundle of His, bundle branches, and Purkinje fibers

What Went Wrong: Functional Change

Excessive calcium enters cardiac muscle cells and vascular smooth muscle cells, causing high blood pressure and chest pain

Major Signs & Symptoms of Excessive Calcium

Arrhythmias, cardiac arrest, and coma

Complications if Untreated

Muscle weakness, fatigue, cramps, twitching, heart failure, and coronary artery disease

Nursing Priorities

Airway, Breathing, Circulation (ABCs) → Assess → Intervene → Safety

Calcium Channel Blockers Function

Treat high blood pressure, angina, and arrhythmias by preventing calcium from entering heart and blood vessel muscle cells