10 Percent Nurse 232

Pathophysiology Basics

Understanding these terms is crucial for assessing and managing diseases.

  • Terminology:

    • Etiology – The cause of a disease (e.g., infection, genetics).

    • Pathogenesis – The process by which a disease develops.

    • Clinical Manifestations – Signs and symptoms a patient presents with.

    • Diagnosis – How we confirm a disease (labs, imaging, physical exam).

    • Treatment Implications – How the disease is managed (meds, procedures).

    • Nursing Implications – What the nurse should monitor or do for the patient.

    • Prognosis – Expected outcome or course of a disease.

    • Natural History – How a disease progresses without treatment.

Stress and Adaptation

  • Acute vs. Chronic Stress:

    • Acute stress is short-term (e.g., exam stress); chronic stress is long-term and contributes to disease.

    • Cortisol & Sympathetic Nervous System:

      • Chronic stress increases cortisol, leading to high blood sugar and suppressed immune function.

      • The sympathetic nervous system (SNS) activates the fight-or-flight response, increasing heart rate and blood pressure.

  • Chronic stress is a risk factor for:

    • Type 2 diabetes (from high blood sugar)

    • Hypertension & heart disease (from prolonged SNS activation)

    • Weakened immune system (due to excessive cortisol)

Mechanisms of Disease & Disorders

  • Fluid & Electrolyte Imbalances:

    • Osmotic pressure maintains fluid balance.

    • Acid-Base Imbalance: pH disruptions impact organ function.

  • Basic Metabolic Panel (BMP) – Key Components:

    • Sodium (Na⁺): Affects fluid balance and nerves.

    • Potassium (K⁺): Affects the heart and muscles.

    • Creatinine: Measures kidney function.

    • Glucose: Important for diabetes management.

Cardiovascular Physiology & Pathophysiology

  • Cardiac Output (CO) = Heart Rate (HR) × Stroke Volume (SV)

    • If CO drops to zero, the patient has no circulation = death.

  • Stroke Volume Components:

    • Preload: The amount of blood in the heart before contraction.

    • Afterload: The resistance the heart pumps against.

    • Contractility: The strength of heart contractions.

  • Blood Pressure (BP) = CO × Systemic Vascular Resistance (SVR)

    • Hypertension (High BP) Risks: Heart failure, kidney damage, stroke.

    • Coronary Artery Disease & Myocardial Infarction (Heart Attack): Reduced blood flow to the heart.

Renal & Respiratory Physiology

  • Kidney Function:

    • Pre-renal failure: Decreased blood flow to the kidneys.

    • Intra-renal failure: Damage within the kidney.

    • Post-renal failure: Blockage of urine flow.

  • Lung Function:

    • Elasticity & Recoil: Lungs must stretch and snap back to push air out.

    • Asthma & COPD: Chronic airway diseases affecting oxygenation.

Endocrine System

  • Regulation of Blood Glucose:

    • Insulin lowers blood sugar (treats diabetes).

    • Negative Feedback Loop: Blood glucose is regulated by insulin & glucagon.

Pharmacology Basics

  1. Pharmacokinetics (How Drugs Move Through the Body)

    • Absorption: How drugs enter the bloodstream.

    • Distribution: How drugs reach tissues.

    • Metabolism: Mostly occurs in the liver (CYP450 enzymes).

    • Excretion: Drugs leave the body via the kidneys.

  2. Pharmacodynamics (How Drugs Work)

    • Agonists: Activate receptors (e.g., opioids).

    • Antagonists: Block receptors (e.g., naloxone).

    • Therapeutic Effect: The intended benefit.

    • Adverse Effect: Unwanted side effects.

Antibiotics & Risks

  • Antimicrobials kill infections, but some are risky:

    • Penicillin: Can cause allergic reactions/anaphylaxis.

    • Vancomycin: Risk for kidney damage.

    • Tetracyclines: Cause tooth discoloration in kids.

    • Aminoglycosides: Renal toxicity.

    • Fluoroquinolones: Risk of Achilles tendon rupture.

    • Sulfonamides: Can cause Stevens-Johnson syndrome (severe rash).

    • Isoniazid: Liver toxicity.

    • Amphotericin: Kidney toxicity.

Pain & Inflammation Medications

  • Opioids (e.g., Morphine, Oxycodone)

    • Risk: Respiratory depression → Give naloxone to reverse.

    • Side Effects: Constipation, sedation.

  • NSAIDs (e.g., Ibuprofen, Aspirin)

    • Risk: Stomach ulcers, bleeding.

    • Aspirin: Inhibits platelets (bleeding risk).

    • Reyes’ Syndrome: Fatal in kids with viral infections.

  • Acetaminophen (Tylenol)

    • Max dose = 4,000 mg/day (risk of liver failure).

  • Prednisone (Steroids)

    • Risks: Ulcers, hyperglycemia, suppressed immune function.

Cardiovascular Medications

  • Medications that affect cardiac output are dangerous:

    • Beta blockers (e.g., Metoprolol) → Lower HR and BP.

    • Digoxin → Lowers HR; Check HR before giving (hold if <60 bpm).

  • Medications that affect BP must be used carefully:

    • ACE inhibitors (-pril) & ARBs (-sartan) lower BP but can increase potassium & cause angioedema.

    • Diuretics (e.g., Furosemide) lower BP but can deplete potassium.

Respiratory Medications

  • Most inhaled medications are safe because they act locally in the lungs.

    • Albuterol (Rescue Inhaler): Fast-acting for asthma attacks.

    • Oral steroids: Raise blood sugar.

Endocrine Medications

  • Insulin: Lowers blood sugar.

    • Types: Rapid-acting, short-acting, long-acting.

    • Hypoglycemia risk: Always check blood sugar before giving.

Key Takeaways for a New RN

  1. Monitor vitals before giving meds that affect HR, BP, or respiration.

  2. Always check labs before giving drugs that affect potassium, kidney function, or glucose.

  3. Understand adverse effects to anticipate and prevent complications.

  4. Use caution with antibiotics due to serious side effects.

  5. Educate patients on medication risks (e.g., opioid safety, NSAID ulcers, steroid hyperglycemia).

Would you like more detail on any section? 😊