UNIT-5- Drugs used in treatment of Cardiovascular system and blood disorders
Introduction to Drugs Used in the Treatment of Cardiovascular System and Blood Disorders
Introduction
The cardiovascular system consists of the heart, blood vessels, and blood circulation, ensuring oxygen and nutrient delivery to tissues. Disorders of the cardiovascular system, such as hypertension, heart failure, angina, arrhythmias, and atherosclerosis, require pharmacological management to prevent complications like stroke and myocardial infarction.
The blood system is responsible for oxygen transport, clotting, and immune responses. Blood disorders, including anemia, clotting disorders (thrombosis, hemophilia), and hematological malignancies, require specific drugs for management.
1. Classification of Drugs Used in Cardiovascular and Blood Disorders
Drugs for Anemia (Increase Red Blood Cell Production)
Examples: Iron supplements, Erythropoietin, Folic acid, Vitamin B12
Drugs for Hematological Disorders (Treat Blood Cancers & Bleeding Disorders)
Examples: Hydroxyurea (Sickle Cell Anemia), Factor VIII (Hemophilia), Immunosuppressants for leukemia
2. Importance of Cardiovascular and Blood Disorder Medications
Reduce morbidity and mortality in heart disease and stroke.
Lower blood pressure and cholesterol levels, reducing heart attack risk.
Prevent and dissolve blood clots, preventing stroke and embolism.
Improve cardiac function in heart failure and arrhythmias.
Correct anemia and prevent complications of blood disorders.
Nurses play a critical role in administering, monitoring, and educating patients about cardiovascular and blood disorder drugs to ensure effective and safe therapy.
Pharmacology of Hematinics and Treatment of Anemia
Introduction
Hematinics are drugs that increase hemoglobin levels and red blood cell (RBC) production by supplying essential nutrients like iron, folic acid, and vitamin B12. They are used in the treatment of anemia, a condition characterized by low hemoglobin levels resulting in fatigue, weakness, pallor, and dyspnea.
Anemia can be classified as:
Iron Deficiency Anemia (IDA) – Due to lack of iron.
Megaloblastic Anemia – Due to vitamin B12 or folic acid deficiency.
Pernicious Anemia – Due to lack of intrinsic factor leading to vitamin B12 deficiency.
Hemolytic Anemia – Due to destruction of RBCs (sickle cell anemia, G6PD deficiency).
Aplastic Anemia – Due to bone marrow failure to produce RBCs.
1. Classification of Hematinics and Drugs for Anemia Treatment
A. Iron Supplements (For Iron Deficiency Anemia)
Examples: Ferrous sulfate, Ferrous fumarate, Ferric carboxymaltose, Iron dextran
Action: Increases hemoglobin production by replenishing iron stores.
B. Vitamin B12 Supplements (For Pernicious & Megaloblastic Anemia)
Examples: Cyanocobalamin, Hydroxocobalamin
Action: Essential for RBC formation and DNA synthesis.
C. Folic Acid (For Megaloblastic Anemia)
Examples: Folic acid, Leucovorin (Folinic Acid)
Action: Required for RBC maturation and fetal development in pregnancy.
D. Erythropoiesis-Stimulating Agents (For Anemia in Chronic Kidney Disease & Cancer)
Monitor hemoglobin, hematocrit, and RBC levels before starting treatment.
Assess iron levels (serum ferritin, transferrin saturation).
Check vitamin B12 and folic acid levels in megaloblastic anemia.
Monitor BP and kidney function before giving erythropoietin.
B. Proper Drug Administration
Iron supplements should be taken on an empty stomach for better absorption.
Vitamin C enhances iron absorption.
Injectable iron must be given via deep IM or IV infusion to avoid reactions.
Monitor for signs of iron toxicity.
C. Patient Education
Teach patients to recognize anemia symptoms (fatigue, dizziness, pallor).
Encourage a diet rich in iron (meat, green leafy vegetables, beans).
Warn about constipation with iron supplements and recommend high-fiber intake.
Vitamin B12 is needed lifelong in pernicious anemia.
Pharmacology of Antiadrenergic Drugs
Introduction
Antiadrenergic drugs are medications that block the effects of adrenergic (sympathetic) stimulation by inhibiting the action of norepinephrine (NE) and epinephrine (adrenaline) on adrenergic receptors. These drugs are used to treat various cardiovascular, neurological, and endocrine disorders, including hypertension, arrhythmias, anxiety, and benign prostatic hyperplasia (BPH).
Antiadrenergic drugs are classified into alpha-blockers, beta-blockers, and centrally acting adrenergic inhibitors based on their site of action.
1. Classification of Antiadrenergic Drugs
A. Alpha-Adrenergic Blockers (Alpha-Blockers)
Block α1 or α2 adrenergic receptors, leading to vasodilation, decreased blood pressure, and improved urinary flow.
Examples:
Selective α1-blockers: Prazosin, Doxazosin, Tamsulosin (Used for hypertension and BPH).
Non-selective α-blockers: Phenoxybenzamine, Phentolamine (Used in pheochromocytoma).
B. Beta-Adrenergic Blockers (Beta-Blockers)
Block β1 and/or β2 adrenergic receptors, leading to reduced heart rate, cardiac output, and blood pressure.
Examples:
Cardioselective (β1-blockers): Atenolol, Metoprolol, Bisoprolol (Used for hypertension, heart failure).
Non-selective β-blockers: Propranolol, Nadolol, Timolol (Used for hypertension, migraines).
Alpha and beta-blockers: Labetalol, Carvedilol (Used for hypertensive emergencies, heart failure).
C. Centrally Acting Adrenergic Inhibitors
Reduce sympathetic outflow from the brain, leading to decreased blood pressure and heart rate.
Examples: Clonidine, Methyldopa, Reserpine (Used for hypertension).
2. Pharmacology of Commonly Used Antiadrenergic Drugs
Overdose Symptoms: Severe drowsiness, hypotension, respiratory depression.
Management: IV fluids, vasopressors.
3. Role of Nurse in Antiadrenergic Drug Administration
A. Assessment Before Administration
Monitor blood pressure and heart rate before giving alpha or beta-blockers.
Assess for asthma or COPD before giving non-selective beta-blockers.
Check renal and hepatic function in elderly patients.
B. Proper Administration and Monitoring
Administer first dose of alpha-blockers at bedtime to avoid first-dose hypotension.
Do not stop beta-blockers suddenly (risk of rebound hypertension and angina).
Monitor for signs of bradycardia and hypotension.
C. Patient Education
Avoid alcohol and sedatives when taking centrally acting drugs (Clonidine).
Rise slowly from sitting or lying positions (to prevent postural hypotension).
Report symptoms of extreme fatigue, dizziness, or difficulty breathing.
4. Summary Table of Common Antiadrenergic Drugs
Drug
Class
Mechanism
Indications
Side Effects
Toxicity Management
Prazosin
α1-blocker
Vasodilation
Hypertension, BPH
Hypotension, dizziness
IV fluids, vasopressors
Propranolol
Non-selective β-blocker
↓ HR, ↓ BP
Hypertension, anxiety
Fatigue, bradycardia
IV glucagon, atropine
Clonidine
Centrally acting α2-agonist
↓ Sympathetic output
Hypertension, ADHD
Dry mouth, drowsiness
IV fluids, vasopressors
Pharmacology of Cholinergic and Anticholinergic Drugs
Introduction
Cholinergic drugs act by stimulating the parasympathetic nervous system (PNS) through acetylcholine (ACh) receptors, leading to increased secretions, smooth muscle contraction, and slowed heart rate. These drugs are used in conditions such as glaucoma, myasthenia gravis, and urinary retention.
Anticholinergic drugs inhibit the action of acetylcholine by blocking its receptors, leading to reduced secretions, bronchodilation, increased heart rate, and smooth muscle relaxation. They are used to treat asthma, Parkinson’s disease, bradycardia, and irritable bowel syndrome (IBS).
1. Classification of Cholinergic and Anticholinergic Drugs
A. Cholinergic Drugs (Parasympathomimetics)
Direct-Acting Cholinergic Agonists
Examples: Bethanechol, Pilocarpine, Carbachol
Action: Bind directly to muscarinic or nicotinic receptors to stimulate PNS activity.
4. Ipratropium (Anticholinergic Drug – Bronchodilator)
Composition
Ipratropium bromide
Action
Blocks muscarinic receptors in the lungs, leading to bronchodilation and reduced mucus secretion.
Dosage and Route
Inhalation (MDI/Nebulizer): 20–40 mcg every 6–8 hours.
Indications
COPD, asthma (for bronchodilation).
Contraindications
Glaucoma, prostatic hyperplasia.
Drug Interactions
Enhances effects of beta-2 agonists (synergistic bronchodilation).
Side Effects
Dry mouth, cough, blurred vision.
Adverse Effects
Paradoxical bronchospasm, urinary retention.
Toxicity
Overdose Symptoms: Tachycardia, confusion.
Management: Supportive care.
3. Role of Nurse in Cholinergic and Anticholinergic Drug Administration
A. Assessment Before Administration
Monitor vital signs (BP, HR, RR) before giving cholinergic or anticholinergic drugs.
Assess bowel and bladder function before giving cholinergics.
Check for history of glaucoma or urinary retention before giving anticholinergics.
B. Proper Administration and Monitoring
Administer cholinergic drugs before meals to improve absorption.
Ensure proper inhalation technique for Ipratropium (rinse mouth after use).
Monitor for signs of cholinergic crisis (excessive salivation, muscle weakness).
C. Patient Education
Avoid driving after taking anticholinergics (causes drowsiness).
Drink plenty of fluids when taking anticholinergics (reduces dry mouth).
Report signs of excessive sweating, diarrhea (signs of cholinergic toxicity).
4. Summary Table of Common Cholinergic and Anticholinergic Drugs
Drug
Class
Mechanism
Indications
Side Effects
Toxicity Management
Bethanechol
Cholinergic agonist
Stimulates bladder contraction
Urinary retention
Nausea, sweating
Atropine (antidote)
Atropine
Anticholinergic
Blocks muscarinic receptors
Bradycardia, pre-anesthesia
Dry mouth, tachycardia
Physostigmine (antidote)
Ipratropium
Anticholinergic
Bronchodilation
COPD, asthma
Dry mouth, cough
Supportive care
Pharmacology of Adrenergic Drugs for Congestive Heart Failure (CHF) and Vasodilators
Introduction
Congestive Heart Failure (CHF) is a condition in which the heart fails to pump blood efficiently, leading to fluid retention, shortness of breath, and fatigue. The goal of treatment is to improve cardiac output, reduce preload and afterload, and enhance myocardial function.
Adrenergic drugs (sympathomimetics) and vasodilators play key roles in managing CHF by stimulating the heart or relaxing blood vessels to improve circulation.
1. Classification of Adrenergic Drugs for CHF and Vasodilators
Severe hypotension, increased intracranial pressure.
Drug Interactions
Severe hypotension with sildenafil (PDE-5 inhibitors).
Side Effects
Headache, dizziness, flushing.
Adverse Effects
Severe hypotension, reflex tachycardia.
Toxicity
Overdose Symptoms: Methemoglobinemia, severe hypotension.
Management: Oxygen therapy, IV fluids, methylene blue (for methemoglobinemia).
4. Hydralazine (Direct Arterial Vasodilator)
Composition
Hydralazine hydrochloride
Action
Dilates arterioles → Reduces afterload and systemic vascular resistance.
Dosage and Route
Oral: 10–50 mg four times daily.
IV (Severe Hypertension/Heart Failure): 10–20 mg IV every 4–6 hours.
Indications
Hypertension, CHF (especially in African American patients with nitrate therapy).
Contraindications
Severe coronary artery disease (risk of angina exacerbation).
Drug Interactions
Enhanced hypotension with diuretics and beta-blockers.
Side Effects
Headache, nausea, tachycardia.
Adverse Effects
Lupus-like syndrome (long-term use).
Toxicity
Overdose Symptoms: Severe hypotension, shock.
Management: IV fluids, vasopressors.
3. Role of Nurse in Adrenergic and Vasodilator Drug Administration
A. Patient Assessment Before Administration
Monitor BP, HR, and ECG before giving adrenergic drugs or vasodilators.
Assess signs of fluid overload in CHF patients.
Check renal function before dopamine administration.
B. Proper Administration and Monitoring
Administer IV adrenergic drugs through central lines (to avoid extravasation).
Titrate vasodilator infusion based on BP and symptoms.
Monitor for headache and dizziness with nitrates.
C. Patient Education
Avoid sudden posture changes after vasodilators (to prevent falls).
Report chest pain or palpitations after adrenergic drug use.
Do not mix nitrates with sildenafil (risk of severe hypotension).
Pharmacology of Anti-Anginal Drugs
Introduction
Angina pectoris is chest pain caused by reduced blood flow (ischemia) to the heart muscle, often due to coronary artery disease (CAD). Anti-anginal drugs reduce myocardial oxygen demand, improve blood flow to the heart, and relieve chest pain.
Antiarrhythmic drugs are used to manage and treat cardiac arrhythmias, which are abnormal heart rhythms resulting from disturbances in the electrical conduction system of the heart. They work by modifying ion channel activity and conduction pathways in cardiac tissue.
1. Classification of Antiarrhythmic Drugs (Vaughan-Williams Classification)
Class
Type
Examples
Mechanism of Action
Class I
Sodium Channel Blockers
Lidocaine, Procainamide, Flecainide
Block sodium channels, reduce excitability, and slow conduction
Class II
Beta-Blockers
Propranolol, Metoprolol, Atenolol
Decrease heart rate, reduce excitability, and inhibit sympathetic stimulation
Class III
Potassium Channel Blockers
Amiodarone, Sotalol, Dofetilide
Prolong repolarization and action potential duration
Class IV
Calcium Channel Blockers
Verapamil, Diltiazem
Slow conduction at the AV node and reduce heart rate
Unclassified
Miscellaneous Agents
Digoxin, Adenosine, Magnesium Sulfate
Affect ion exchange, AV node conduction, or atrial tissue activity
2. Composition of Antiarrhythmic Drugs
Each antiarrhythmic drug has different active ingredients based on its class. Below are a few examples:
Avoid grapefruit juice (interferes with metabolism of some drugs)
Importance of regular ECG and blood tests
Antihypertensives
Antihypertensive drugs are used to manage hypertension (high blood pressure) by targeting different physiological mechanisms to lower blood pressure and reduce the risk of complications such as stroke, heart attack, and kidney disease.
1. Classification of Antihypertensive Drugs
Class
Examples
Mechanism of Action
1. Diuretics
Hydrochlorothiazide, Furosemide, Spironolactone
Increase urine output, reduce blood volume
2. Beta-Blockers
Propranolol, Atenolol, Metoprolol
Block β-receptors, reduce heart rate and cardiac output
3. Calcium Channel Blockers (CCBs)
Amlodipine, Verapamil, Diltiazem
Block calcium channels, relax blood vessels
4. Angiotensin-Converting Enzyme (ACE) Inhibitors
Enalapril, Lisinopril, Ramipril
Block conversion of Angiotensin I to II, reducing vasoconstriction
5. Angiotensin II Receptor Blockers (ARBs)
Losartan, Valsartan, Telmisartan
Block angiotensin II receptors, preventing vasoconstriction
aPTT for heparin therapy (maintain 1.5-2.5 times normal value)
After Administration
✅ Evaluate:
Therapeutic response (controlled bleeding or clot prevention)
Monitor for side effects (bruising, bleeding, hypotension)
Patient Education
Avoid excessive green leafy vegetables (for warfarin users)
Report unusual bleeding, dark stools, or bruising
Regular INR testing for warfarin therapy
Avoid NSAIDs and aspirin unless prescribed
Do not stop anticoagulants suddenly without consulting a doctor.
Antiplatelets & Thrombolytics:
1. Introduction
Antiplatelets are drugs that prevent platelet aggregation and thrombus formation in arteries, reducing the risk of heart attack and stroke.
Thrombolytics (Fibrinolytics) are drugs that dissolve existing blood clots by breaking down fibrin, used in emergency situations like myocardial infarction (MI) and ischemic stroke.
2. Classification of Antiplatelets & Thrombolytics
Blood pressure (for hypotension with thrombolytics)
ECG monitoring in thrombolytic therapy
After Administration
✅ Evaluate:
Therapeutic effect (prevented clot formation or dissolved clot)
Monitor for side effects (GI bleeding, bruising)
Patient Education
Aspirin & Clopidogrel: Take with food to prevent stomach irritation.
Report unusual bleeding, dark stools, or bruising immediately.
Avoid NSAIDs and alcohol while taking antiplatelets.
Thrombolytics: Avoid invasive procedures after administration.
Hypolipidemics (Lipid-Lowering Agents):
1. Introduction
Hypolipidemic drugs are used to lower lipid levels, primarily cholesterol and triglycerides, in order to prevent cardiovascular diseases like atherosclerosis, coronary artery disease (CAD), and stroke.
2. Classification of Hypolipidemic Drugs
Class
Examples
Mechanism of Action
1. HMG-CoA Reductase Inhibitors (Statins)
Atorvastatin, Rosuvastatin, Simvastatin
Inhibit HMG-CoA reductase, reducing cholesterol synthesis in the liver
2. Bile Acid Sequestrants
Cholestyramine, Colesevelam
Bind bile acids in the intestine, promoting excretion and reducing cholesterol
Omega-3: Monitor for bleeding (especially if on anticoagulants).
After Administration
✅ Evaluate:
Lipid levels (LDL ↓, HDL ↑, Triglycerides ↓)
Patient adherence to therapy
Adverse effects (muscle pain, GI issues)
Patient Education
Statins: Take at night (cholesterol synthesis peaks at night).
Avoid grapefruit juice with statins.
Niacin flushing can be reduced by taking aspirin 30 min before.
Increase fiber intake if using bile acid sequestrants.
Regular blood tests to monitor liver function.
Plasma Expanders & Treatment of Shock:
1. Introduction
Plasma expanders are intravenous fluids used to increase blood volume in cases of hypovolemia, such as in shock, severe dehydration, burns, and hemorrhage. They work by drawing fluid into the vascular compartment, maintaining circulatory stability.
Shock: Definition & Types
Shock is a life-threatening condition in which blood flow to organs is inadequate, leading to organ dysfunction and failure. It is classified into:
Hypovolemic Shock: Due to fluid or blood loss (e.g., hemorrhage, burns).
Cardiogenic Shock: Due to heart failure (e.g., myocardial infarction).
Distributive Shock:
Septic Shock: Due to severe infection.
Neurogenic Shock: Due to spinal cord injury.
Anaphylactic Shock: Due to severe allergic reaction.
Obstructive Shock: Due to blockage of blood flow (e.g., pulmonary embolism, cardiac tamponade).
HES Toxicity: Severe renal impairment, coagulation defects.
Management of Toxicity:
Stop infusion immediately.
Administer diuretics for fluid overload.
Provide supportive care (oxygen, dialysis if needed).
11. Treatment of Shock
General Management:
✅ Identify the cause of shock ✅ Maintain airway and oxygenation (O2 therapy, intubation if needed) ✅ Restore circulation using IV fluids & vasopressors
IV fluids (Crystalloids, Albumin), Antibiotics, Vasopressors
Neurogenic Shock
IV fluids, Vasopressors (Norepinephrine)
Anaphylactic Shock
Epinephrine, IV fluids, Antihistamines
12. Role of the Nurse
Before Administration
✅ Assess:
Blood pressure, heart rate
Oxygen saturation
Fluid status (dehydration, edema)
During Administration
✅ Monitor:
Vital signs (BP, HR, RR)
Urine output (kidney function)
Signs of fluid overload (shortness of breath, swelling)
After Administration
✅ Evaluate:
Improved BP & perfusion
Resolution of shock symptoms
Watch for side effects (allergic reactions, overload)
Patient Education
Avoid excessive fluid intake if at risk for overload.
Report swelling or breathing difficulty immediately.
Regular monitoring for electrolyte imbalances.
Nurses’ Role and Responsibilities in Drugs Used for Cardiovascular System and Blood Disorders
1. Introduction
Nurses play a critical role in administering, monitoring, and educating patients about cardiovascular and hematologic medications. Their responsibilities include ensuring safety, preventing complications, and promoting adherence to treatment.
2. Common Drugs Used in Cardiovascular and Blood Disorders
Drug Class
Examples
Indications
1. Antihypertensives
Amlodipine, Lisinopril, Losartan, Metoprolol
Hypertension, heart failure
2. Antiarrhythmics
Amiodarone, Lidocaine, Digoxin
Arrhythmias (AF, VT)
3. Antiplatelets
Aspirin, Clopidogrel, Ticagrelor
MI, Stroke prevention
4. Anticoagulants
Heparin, Warfarin, Dabigatran, Rivaroxaban
DVT, PE, AF, Stroke prevention
5. Thrombolytics
Alteplase (tPA), Streptokinase
MI, Ischemic Stroke, PE
6. Hypolipidemics
Atorvastatin, Rosuvastatin
High cholesterol, CAD prevention
7. Vasodilators
Nitroglycerin, Hydralazine
Angina, Heart failure
8. Diuretics
Furosemide, Hydrochlorothiazide
Hypertension, Edema, CHF
9. Inotropes
Dopamine, Dobutamine
Heart failure, Shock
10. Erythropoiesis-Stimulating Agents
Erythropoietin, Darbepoetin
Anemia due to CKD, Chemotherapy
11. Iron Supplements
Ferrous sulfate, Iron dextran
Iron deficiency anemia
12. Vitamin B12/Folic Acid
Cyanocobalamin, Folic Acid
Pernicious anemia, Megaloblastic anemia
3. Nurses’ Responsibilities in Drug Administration
A. Before Administration
✅ Assess patient’s baseline status:
BP & HR for cardiovascular drugs
Bleeding risk for anticoagulants & antiplatelets
Lipid profile for statins
Kidney/liver function for drug metabolism
✅ Check laboratory values:
PT/INR (Warfarin)
aPTT (Heparin)
Electrolytes (Diuretics, Digoxin)
Renal function (Creatinine, GFR) for ACE inhibitors & diuretics
✅ Ensure correct dose and route:
Antihypertensives: Oral or IV, depending on severity
Diuretics: IV in emergency, Oral for maintenance
Thrombolytics: IV bolus + infusion
Anticoagulants: IV Heparin, Oral Warfarin
✅ Check for contraindications:
Beta-blockers: Avoid in asthma/COPD
ACE inhibitors: Avoid in pregnancy
Thrombolytics: Avoid in recent surgery, bleeding disorders
Statins: Avoid in liver disease
✅ Obtain informed consent (if required for high-risk drugs like thrombolytics).