10 percent

Pathophysiology (Patho)

Terminology

  • Etiology: The cause of a disease (e.g., smoking causes lung cancer).

  • Pathogenesis: How the disease develops (e.g., smoking damages lung cells, leading to cancer).

  • Clinical Manifestations: Signs and symptoms of the disease (e.g., cough, shortness of breath).

  • Diagnosis: How the disease is identified (e.g., chest X-ray, biopsy).

  • Treatment Implications: What treatments are used (e.g., chemotherapy, surgery).

  • Nursing Implications: What nurses need to monitor or do (e.g., assess lung function, educate on smoking cessation).

  • Prognosis: The likely outcome of the disease (e.g., good prognosis if caught early).

  • Natural History: How the disease progresses without treatment (e.g., lung cancer may spread if untreated).

Acute Stress vs. Chronic Stress

  • Acute Stress: Short-term stress (e.g., running late for work). The body releases adrenaline and cortisol, but it’s temporary.

  • Chronic Stress: Long-term stress (e.g., ongoing financial problems). This keeps cortisol levels high, which can lead to health problems like diabetes, hypertension, and heart disease.

Cortisol & the Sympathetic Nervous System

  • Cortisol is a stress hormone. Chronic high levels can:

    • Increase blood sugar (risk for Type 2 Diabetes).

    • Raise blood pressure (risk for Hypertension/Heart Disease).

Inflammatory Response/Immunity

  • When the body is injured or infected, it triggers inflammation to heal itself. Chronic inflammation can harm tissues (e.g., in arthritis).

Fluid and Electrolyte Imbalance

  • Sodium (Na+): Controls fluid balance. Too high (hypernatremia) or too low (hyponatremia) can cause brain swelling or dehydration.

  • Potassium (K+): Important for heart and muscle function. Too high (hyperkalemia) can cause heart arrhythmias; too low (hypokalemia) can cause muscle weakness.

  • Creatinine: A waste product from muscles. High levels may indicate kidney problems.

  • Glucose: Blood sugar. High levels (hyperglycemia) can indicate diabetes.

Cardiovascular Physiology/Pathophysiology

Cardiac Output (CO)

  • CO = Heart Rate (HR) × Stroke Volume (SV). If CO is too low, organs don’t get enough blood (e.g., shock).

Stroke Volume (SV)

  • The amount of blood the heart pumps per beat. It depends on:

    • Preload: How much blood fills the heart before it contracts (like stretching a rubber band).

    • Afterload: The resistance the heart must pump against (like pushing against a heavy door).

    • Contractility: How strong the heart muscle contracts.

Blood Pressure (BP)

  • BP = Cardiac Output × Systemic Vascular Resistance (SVR). High BP (hypertension) can damage blood vessels and organs.

Coronary Artery Disease (CAD)

  • Plaque builds up in the arteries, reducing blood flow to the heart. Can lead to chest pain (angina) or heart attack.

Acute Myocardial Infarction (AMI)

  • A heart attack! Part of the heart muscle dies due to lack of blood flow.

Renal Physiology/Pathophysiology

  • Pre-renal: Problem before the kidney (e.g., low blood flow).

  • Intra-renal: Problem inside the kidney (e.g., damage from toxins).

  • Post-renal: Problem after the kidney (e.g., blocked urine flow).

Respiratory Physiology/Pathophysiology

  • Elasticity: How well the lungs stretch.

  • Recoil: How well the lungs return to normal after stretching.

  • Asthma: Airways narrow, making it hard to breathe.

  • COPD: Chronic lung disease (e.g., emphysema, chronic bronchitis).

Endocrine Physiology/Pathophysiology

  • Hypothalamus-Pituitary Axis: Controls hormones like cortisol, thyroid, and growth hormones.

  • Negative Feedback: Hormone levels are regulated by feedback loops (e.g., high blood sugar triggers insulin release).

  • Diabetes: High blood sugar due to lack of insulin or insulin resistance.

Pharmacology (Pharm)

Pharmacokinetics

  • Absorption: How the drug gets into the bloodstream (e.g., oral, IV).

  • Distribution: How the drug spreads through the body.

  • Metabolism: How the drug is broken down (often in the liver).

  • Excretion: How the drug leaves the body (often through kidneys).

Pharmacodynamics

  • Agonist: Activates a receptor (e.g., morphine activates pain receptors).

  • Antagonist: Blocks a receptor (e.g., naloxone blocks opioid receptors).

Antibiotics

  • Penicillin: Can cause allergic reactions (anaphylaxis).

  • Vancomycin: Can harm kidneys.

  • Tetracyclines: Can stain teeth.

  • Aminoglycosides: Can cause kidney damage.

  • Fluoroquinolones: Can cause tendon rupture.

  • Sulfonamides: Can cause Stevens-Johnson syndrome (a severe skin reaction).

Pain & Inflammation Medications

  • Opioids: Can cause respiratory depression (slowed breathing). Reversed by Naloxone.

  • NSAIDs: Can cause stomach ulcers and bleeding.

  • Aspirin: Can increase bleeding risk. Avoid in kids (risk of Reyes’ syndrome).

  • Acetaminophen: Safe in normal doses, but high doses can damage the liver.

Cardiovascular Medications

  • Beta Blockers: Lower heart rate and blood pressure. Hold if HR < 60 bpm.

  • Digoxin: Slows heart rate. Monitor for toxicity (nausea, vision changes).

  • ACE Inhibitors/ARBs: Lower blood pressure but can raise potassium levels and cause angioedema (swelling of lips/tongue).

  • Diuretics: Remove excess fluid. Some can lower potassium (e.g., furosemide), while others can raise it (e.g., spironolactone).

Respiratory Medications

  • Albuterol: A quick-acting inhaler for asthma attacks.

  • Oral Steroids: Can raise blood sugar and cause other systemic effects.

Endocrine Medications

  • Insulin: Lowers blood sugar. Different types work at different speeds (rapid-acting, long-acting, etc.).

  • Hypoglycemia: Low blood sugar. Can be dangerous—always monitor glucose levels.