Congestive Heart Failure Overview

Congestive Heart Failure (CHF)

• Hypertrophy (muscle enlargement) is a feature of CHF
• Preload is pressure in the right atrium
• Afterload is resistance left ventricle faces to push oxygenated blood
• Right-sided CHF: fluid backs up in periphery (e.g., liver, feet)
• Left-sided CHF: fluid backs up in lungs causing dyspnea and pulmonary edema
• CHF symptoms include: fluid overload, dyspnea, pulmonary congestion, orthopnea, cyanosis, tripod positioning, peripheral venous pressure, ascites, enlarged liver/spleen, distended jugular veins, and weight gain/dependent edema
• Four stages of CHF
• Non-pharmacologic treatment includes limiting salt, alcohol, saturated fat, and encouraging exercise
• Diagnostic tests: BNP (<100) or echocardiogram (EF <50%)
• Digoxin (Lanoxin) is a cardiac glycoside that increases contractility, decreases heart rate, decreases conduction, and increases stroke volume
• Check heart rate before digoxin administration
• Diuretics interact with digoxin, leading to hypokalemia
• Digoxin toxicity symptoms: GI symptoms, bradycardia, visual disturbances (yellow halos)
• Digibind is the antidote for digoxin toxicity
• Milrinone (Primacor) is a phosphodiesterase inhibitor for short-term CHF
• Primacor is administered IV in ICU and has fatal ventricular dysrhythmias as potential adverse effects
• Nesiritide (Natrecor) is a natriuretic peptide for acute heart failure, common adverse effect is hypotension
• ACE inhibitors, diuretics and potassium are nephrotoxic, monitor BUN & creatinine
• Atherosclerosis is a cause of coronary artery disease & high lipid intake
• Lipid build-up from high dietary lipids is a major cause of coronary artery disease
• Treat CHF by unloading the patient quickly

Angina (Chest Pain)

• Angina is a major symptom of coronary artery disease
• Nitroglycerin is an antianginal drug. Adverse effects include hypotension and headache
• Nitroglycerin relaxes coronary arteries, a vasodilator
• Important to check blood pressure before administering Nitroglycerin
• Nitroglycerin should be taken via oral or topical route avoiding sunlight
• Atenolol is a beta blocker reducing oxygen need & anginal pain
• P wave = atrial activation; QRS = ventricular activation; T wave = recovery
• Class 3 antidysrhythmics like amiodarone & dronedarone prolong repolarization and are used to treat ventricular dysrhythmias
• Diltiazem treats atrial fibrillation
• Emergency drugs for cardiac disorders: MONA (Morphine, Oxygen, Nitroglycerin, Aspirin)

Respiratory Agents

• Three lobes in the right lung, two in the left due to the heart's presence
• Ventilation is the process of oxygen passing through the airways
• Perfusion is the blood flow to the alveolar capillaries
• Ventilation/perfusion ratio (V/Q ratio) is ideally equal
• Diffusion involves gas exchange between oxygen and carbon dioxide
• Common cold symptoms include sneezing, nasal congestion, cough, and sore throat; use nonpharmacologic remedies.
• Decongestants (e.g., pseudoephedrine or oxymetazoline) stimulate alpha-adrenergic receptors for nasal mucosa shrinkage. Adrenergic medications should be used with caution.
• Antihistamines treat allergic reactions, induce sleep, help with common cold symptoms, and treat motion sickness/Nausea
• Antihistamines block the histamine 1 receptor.
• Intranasal glucocorticoids are used to control inflammation, and can cause nasal dryness
• Obstructive pulmonary diseases: Emphysema, COPD, Asthma
• Restrictive pulmonary diseases: Fluid accumulation or elasticity loss, e.g., tumors or Scoliosis
• Chronic obstructive pulmonary disease (COPD) reduces airflow reversibly.
• Emphysema permanently enlarges alveoli and destroys alveolar walls.
• Chronic bronchitis involves mucus hypersecretion and continuous productive cough.
• Asthma involves airway inflammation, often related to allergens or irritants, causing constriction and increased mucus.
• Albuterol is a beta2-agonist bronchodilator used in acute attacks (rescue inhaler)
• Ipratropium bromide helps decrease bronchoconstriction and mucus secretion
• Xanthines such as theophylline enhance bronchodilation/decrease bronchospasm.
• Corticosteroids such as beclomethasone reduce inflammation in asthma or COPD.
• Leukotriene modifiers like montelukast reduce inflammatory symptoms of asthma
• Cromolyn prevents histamine release, used prophylactically in asthma

UTI Infections

• Acute pyelonephritis is a kidney infection (often E.coli in females). Symptoms include chills, fever, flank pain, urinary symptoms (dysuria, frequency, urgency).
• Acute cystitis is a bladder infection (often E.coli or other bacteria). Symptoms are similar to pyelonephritis, but without flank pain.
• Bactrim, Nitrofurantoin, Ciprofloxacin are antibiotics used to treat UTIs. Specific advice regarding individual drugs is provided in a separate study section.

Immunizations

• Active immunity involves the body's immune response to an antigen; creating its own antibodies (from vaccines).
• Passive immunity involves receiving pre-formed antibodies(via breastmilk, plasma transfusion, etc)
• Vaccination is an example of active immunity.
• Many vaccines are contraindicated during pregnancy.
• Influenza IM shots are acceptable during pregnancy
• Common bacterial illnesses, like smallpox and anthrax; some infections can be caused through bioterrorism