Pharmacology for Nurses

💊Pharmacology for Nurses Unit 6 – Immune System and Inflammation Basics

The immune system is our body's defense against harmful invaders. It's a complex network of cells, tissues, and organs working together to protect us from pathogens and foreign substances. Understanding its components and functions is crucial for nurses to provide effective care. Inflammation is a key process in the immune response, helping to fight infections and heal injuries. However, when inflammation becomes chronic, it can lead to various disorders. Nurses must recognize signs of inflammation, understand its causes, and be familiar with treatment options to manage inflammatory conditions effectively.

Key Concepts and Terminology

  • Innate immunity provides immediate, non-specific defense against pathogens and foreign substances
  • Adaptive immunity develops over time, providing specific and long-lasting protection against specific antigens
  • Antigens are substances that trigger an immune response (bacteria, viruses, allergens)
  • Antibodies are proteins produced by B cells that neutralize or mark antigens for destruction
  • Cytokines are signaling molecules that regulate immune responses and inflammation (interleukins, interferons, tumor necrosis factors)
    • Proinflammatory cytokines promote inflammation (IL-1, IL-6, TNF-α)
    • Anti-inflammatory cytokines suppress inflammation (IL-4, IL-10, TGF-β)
  • Leukocytes are white blood cells involved in immune responses (neutrophils, lymphocytes, monocytes, eosinophils, basophils)
  • Complement system consists of proteins that enhance the immune response and promote inflammation

Anatomy of the Immune System

  • Lymphoid organs are tissues that produce, mature, and store lymphocytes
    • Primary lymphoid organs include the bone marrow and thymus
    • Secondary lymphoid organs include lymph nodes, spleen, and mucosa-associated lymphoid tissue (MALT)
  • Lymphatic system transports lymph fluid, immune cells, and antigens throughout the body
  • Bone marrow is the site of hematopoiesis, producing all blood cells, including immune cells
  • Thymus is the site of T cell maturation and selection
  • Lymph nodes filter lymph fluid and provide a site for antigen presentation and lymphocyte activation
  • Spleen filters blood, removes aged or damaged blood cells, and stores platelets and immune cells
  • MALT is found in mucosal surfaces (respiratory, gastrointestinal, urogenital tracts) and provides local immune protection

Types of Immune Responses

  • Cell-mediated immunity involves T cells directly attacking infected or abnormal cells
    • Cytotoxic T cells (CD8+) destroy infected or cancerous cells
    • Helper T cells (CD4+) coordinate immune responses by secreting cytokines and activating other immune cells
    • Regulatory T cells (Tregs) suppress immune responses to prevent autoimmunity and excessive inflammation
  • Humoral immunity involves B cells producing antibodies that neutralize or mark antigens for destruction
    • Plasma cells are differentiated B cells that secrete large amounts of antibodies
    • Memory B cells provide long-lasting immunity and rapid antibody production upon re-exposure to an antigen
  • Innate immune responses are immediate and non-specific, involving physical and chemical barriers, phagocytic cells, and inflammation
    • Physical barriers include skin, mucous membranes, and cilia
    • Chemical barriers include enzymes (lysozyme), antimicrobial peptides (defensins), and acidic pH
    • Phagocytic cells (neutrophils, macrophages) engulf and destroy pathogens
  • Adaptive immune responses are specific and develop over time, involving T cells and B cells
    • Antigen presentation by dendritic cells and macrophages activates T cells and B cells
    • Clonal expansion of activated lymphocytes produces large numbers of antigen-specific cells
    • Memory cells provide long-lasting immunity and rapid response upon re-exposure to an antigen

Inflammation Process and Mediators

  • Inflammation is a protective response to tissue injury or infection, characterized by redness, swelling, heat, pain, and loss of function
  • Acute inflammation is a short-term response that promotes healing and resolves within days to weeks
    • Vasodilation increases blood flow to the affected area, causing redness and heat
    • Increased vascular permeability allows fluid and immune cells to enter the tissue, causing swelling
    • Pain results from the release of prostaglandins and other inflammatory mediators
  • Chronic inflammation is a prolonged response that can lead to tissue damage and contribute to various diseases (atherosclerosis, cancer, autoimmune disorders)
  • Inflammatory mediators are substances that initiate, amplify, and regulate the inflammatory response
    • Histamine is released by mast cells and basophils, causing vasodilation and increased vascular permeability
    • Prostaglandins are lipid mediators that promote vasodilation, pain, and fever
    • Leukotrienes are lipid mediators that promote bronchoconstriction, increased vascular permeability, and leukocyte recruitment
    • Cytokines (IL-1, IL-6, TNF-α) promote the acute phase response, leukocyte activation, and fever
  • Resolution of inflammation involves the clearance of inflammatory mediators, apoptosis of immune cells, and tissue repair
    • Lipoxins, resolvins, and protectins are lipid mediators that promote the resolution of inflammation
    • Anti-inflammatory cytokines (IL-4, IL-10, TGF-β) suppress immune responses and promote tissue repair

Common Inflammatory Disorders

  • Rheumatoid arthritis is an autoimmune disorder characterized by chronic inflammation of the joints, leading to pain, stiffness, and deformity
  • Inflammatory bowel diseases (Crohn's disease, ulcerative colitis) involve chronic inflammation of the gastrointestinal tract, causing abdominal pain, diarrhea, and weight loss
  • Asthma is a chronic inflammatory disorder of the airways, characterized by bronchoconstriction, mucus production, and airway hyperresponsiveness
  • Psoriasis is a chronic inflammatory skin disorder characterized by the formation of scaly, itchy, and painful plaques
  • Allergic reactions involve an exaggerated immune response to harmless substances (allergens), leading to inflammation and symptoms such as itching, swelling, and difficulty breathing
    • Type I hypersensitivity reactions are mediated by IgE antibodies and mast cell degranulation (anaphylaxis, allergic rhinitis, asthma)
    • Type IV hypersensitivity reactions are mediated by T cells and delayed inflammation (contact dermatitis)
  • Sepsis is a life-threatening condition caused by an overwhelming inflammatory response to infection, leading to organ dysfunction and shock

Pharmacological Interventions

  • Nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit cyclooxygenase (COX) enzymes, reducing the production of prostaglandins and inflammation
    • Examples include ibuprofen, naproxen, and celecoxib
    • Adverse effects may include gastrointestinal irritation, bleeding, and renal impairment
  • Corticosteroids are potent anti-inflammatory drugs that suppress the immune response by inhibiting the production of cytokines and other inflammatory mediators
    • Examples include prednisone, methylprednisolone, and dexamethasone
    • Adverse effects may include immunosuppression, osteoporosis, and metabolic disturbances
  • Disease-modifying antirheumatic drugs (DMARDs) are used to slow the progression of rheumatoid arthritis by suppressing the immune response
    • Examples include methotrexate, sulfasalazine, and hydroxychloroquine
    • Adverse effects may include hepatotoxicity, bone marrow suppression, and gastrointestinal disturbances
  • Biologic agents are targeted therapies that inhibit specific inflammatory mediators or pathways
    • Examples include TNF-α inhibitors (etanercept, infliximab), IL-6 inhibitors (tocilizumab), and IL-1 inhibitors (anakinra)
    • Adverse effects may include increased risk of infections, injection site reactions, and rarely, malignancies
  • Antihistamines block the effects of histamine, reducing symptoms of allergic reactions
    • Examples include diphenhydramine, loratadine, and cetirizine
    • Adverse effects may include sedation, dry mouth, and urinary retention
  • Leukotriene modifiers (montelukast, zafirlukast) inhibit the effects of leukotrienes, reducing inflammation in asthma and allergic rhinitis

Nursing Considerations and Patient Education

  • Assess patients for signs and symptoms of inflammation, such as redness, swelling, pain, and fever
  • Monitor patients for adverse effects of anti-inflammatory medications, such as gastrointestinal irritation, bleeding, and immunosuppression
  • Educate patients about the proper use and potential side effects of their medications
    • Encourage patients to take NSAIDs with food or milk to reduce gastrointestinal irritation
    • Advise patients to report any signs of infection, such as fever, chills, or persistent cough, when taking immunosuppressive medications
  • Promote lifestyle modifications that may reduce inflammation and improve overall health
    • Encourage a balanced diet rich in fruits, vegetables, whole grains, and omega-3 fatty acids
    • Recommend regular exercise and stress management techniques
    • Advise patients to avoid smoking and limit alcohol consumption
  • Provide emotional support and resources for patients with chronic inflammatory disorders
    • Refer patients to support groups or counseling services
    • Encourage patients to communicate openly with their healthcare team about their concerns and treatment goals
  • Collaborate with other healthcare professionals, such as physicians, pharmacists, and physical therapists, to provide comprehensive care for patients with inflammatory disorders

Clinical Applications and Case Studies

  • Case 1: A 45-year-old woman presents with joint pain, stiffness, and swelling in her hands and wrists. She is diagnosed with rheumatoid arthritis and started on methotrexate and low-dose prednisone.
    • Nursing considerations: Monitor for adverse effects of medications, provide patient education on proper medication use and lifestyle modifications, and assess for improvement in symptoms and quality of life.
  • Case 2: A 28-year-old man with a history of asthma presents to the emergency department with shortness of breath, wheezing, and chest tightness. He is treated with nebulized albuterol and oral prednisone.
    • Nursing considerations: Assess for improvement in respiratory symptoms, monitor for adverse effects of medications, and provide patient education on proper inhaler technique and avoidance of asthma triggers.
  • Case 3: A 60-year-old woman with a history of osteoarthritis presents with worsening knee pain and swelling. She is prescribed ibuprofen and referred to physical therapy.
    • Nursing considerations: Educate the patient on proper use of NSAIDs, encourage adherence to physical therapy exercises, and assess for improvement in pain and mobility.
  • Case 4: A 35-year-old man with a history of psoriasis presents with new, painful, and scaly plaques on his elbows and knees. He is started on topical corticosteroids and referred to a dermatologist for further evaluation.
    • Nursing considerations: Provide patient education on proper application of topical medications, encourage adherence to treatment plan, and assess for improvement in skin lesions and quality of life.
  • Case 5: A 50-year-old woman with a history of allergic rhinitis presents with sneezing, nasal congestion, and itchy eyes during the spring season. She is prescribed an intranasal corticosteroid and an oral antihistamine.
    • Nursing considerations: Educate the patient on proper use of intranasal sprays and oral medications, encourage avoidance of allergens, and assess for improvement in symptoms and quality of life.


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© 2024 Fiveable Inc. All rights reserved.
AP® and SAT® are trademarks registered by the College Board, which is not affiliated with, and does not endorse this website.
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