NURS6501 Advanced Pathophysiology Walden University MSN Program Carol Cough RN MSNc Res...

1. Patho & Etoiology

1.1. Infection and Inflammation: • Pathogen Entry: Pneumonia can be caused by bacteria, viruses, fungi, or parasites. The most common bacterial cause is Streptococcus pneumoniae • Immune Response: Once the pathogen enters the lungs, the body's immune system responds by sending white blood cells to the alveoli (air sacs) to fight the infection. This leads to inflammation and the release of cytokines and other inflammatory mediators

1.1.1. Alveolar Involvement: • Fluid Accumulation: The inflammation causes the alveoli to fill with fluid, pus, and cellular debris. This accumulation impairs gas exchange, leading to symptoms like cough, shortness of breath, and chest pain • Consolidation: The affected lung tissue becomes consolidated, meaning it becomes solid due to the filling of the alveoli with inflammatory exudate

1.1.2. Impaired Gas Exchange: • Hypoxemia: The fluid-filled alveoli cannot effectively exchange oxygen and carbon dioxide, leading to decreased oxygen levels in the blood (hypoxemia) • Respiratory Distress: The impaired gas exchange can cause respiratory distress, characterized by rapid breathing, cyanosis (bluish skin), and fatigue Option

1.1.3. Systemic Effects: • Fever and Malaise: The systemic inflammatory response can cause fever, chills, and general malaise • Sepsis: In severe cases, the infection can spread to the bloodstream, leading to sepsis, a life-threatening condition characterized by widespread inflammation and organ dysfunction Resolution and Healing: • Immune Clearance: The immune system eventually clears the infection, and the inflammatory response subsides • Tissue Repair: The damaged lung tissue begins to heal, and normal lung function is gradually restored

1.1.4. Bacterial Causes • Streptococcus pneumoniae: The most common cause of bacterial pneumonia • Haemophilus influenzae: Another common bacterial cause • Mycoplasma pneumoniae: Causes atypical or "walking" pneumonia, which tends to have milder symptoms • Legionella pneumophila: Causes Legionnaires' disease, a severe form of pneumonia Viral Causes • Influenza Virus: Can lead to viral pneumonia, especially in high-risk groups • Respiratory Syncytial Virus (RSV): Common in infants and young children • SARS-CoV-2: The virus responsible for COVID-19, which can cause severe pneumonia Fungal Causes • Pneumocystis jirovecii: Often affects individuals with weakened immune systems, such as those with HIV/AIDS • Cryptococcus: Can cause pneumonia, particularly in immunocompromised individuals • Histoplasma: Found in soil contaminated with bird or bat droppings Other • Aspiration Pneumonia: Occurs when food, liquid, or vomit is inhaled into the lungs • Hospital-Acquired Pneumonia: Can occur in hospitalized patients, especially those on ventilators (National Heart, Lung, and Blood Institute, 2022)

1.1.5. Risk Factors (genetic/ethnic/physical) • Extended supine position • NPO or NG tube • Age (infants and elderly) • Chronic diseases (e.g., COPD, asthma) • Smoking • Weakened immune system (e.g., HIV/AIDS, cancer-low neutrophil) • Recent respiratory infections (e.g., cold, flu) • Exposure (Mayo Clinic, 2020)

2. Signs & Symp

2.1. Adults: • Cough with sputum • Chills • Fever • Shortness of breath/Tachypnea • Chest /Pleuritic pain • Fatigue • Rhonchi and wheezes • Accessory muscles use • Nausea, vomiting, diarrhea • Loss of appetite • Blue lips/fingernails • Mental status change Pediatrics: • Rapid breathing • Grunting/wheezing • Fussiness/lethargy • Feeding difficulty (National Heart, Lung, and Blood Institute, 2022)

2.1.1. Option

2.1.2. Option

2.1.3. Option

3. Impact & Comp

3.1. Respiratory System • Lungs: Pneumonia causes inflammation of the alveoli (air sacs) in the lungs, which fill with pus and fluid. This impairs gas exchange, leading to symptoms like cough, shortness of breath, and chest pain • Airways: The infection can cause bronchial inflammation, leading to increased mucus production and airway obstruction Cardiovascular System • Heart: Severe pneumonia can lead to increased heart rate (tachycardia) and, in some cases, heart failure due to the increased workload on the heart to pump oxygenated blood • Blood Vessels: The infection can cause systemic inflammation, leading to vasodilation and hypotension (low blood pressure) Immune System • Inflammatory Response: The body's immune response to the infection involves the release of cytokines and other inflammatory mediators, which can cause fever, chills, and fatigue • Sepsis: In severe cases, the infection can spread to the bloodstream, leading to sepsis, a life-threatening systemic inflammatory response Nervous System • Brain: High fever and systemic inflammation can lead to confusion, delirium, and, in severe cases, encephalopathy (brain dysfunction) Musculoskeletal System • Muscles: The systemic inflammatory response can cause muscle aches and weakness • Joints: In some cases, infection can lead to reactive arthritis, causing joint pain and swelling Digestive System • Liver: The infection and systemic inflammation can affect liver function, leading to elevated liver enzymes • Gastrointestinal Tract: Symptoms like nausea, vomiting, and diarrhea can occur due to the body's response to the infection Renal System • Kidneys: Severe pneumonia and sepsis can lead to acute kidney injury due to decreased blood flow and oxygenation Complications: • Shock and respiratory failure • Hypotension • Pleural effusion • Empyema (Mayo Clinic, 2020) Weight: (1-5)

4. Tests

4.1. Chest X-ray: Purpose: To visualize the lungs and identify areas of inflammation or consolidation, which are indicative of pneumonia • Differentials: Helps distinguish pneumonia from other conditions like congestive heart failure (CHF), lung cancer, and pulmonary embolism Blood Tests: • Complete Blood Count (CBC): To check for elevated white blood cell count, indicating an infection • Blood Cultures: To identify the specific pathogen causing the infection and check for bacteremia (bacteria in the blood) Pulse Oximetry: • Purpose: To measure the oxygen level in the blood, which can be decreased in pneumonia • Differentials: Helps assess the severity of respiratory compromise, which can also be seen in conditions like COPD and asthma Sputum Test: • Purpose: To analyze a sample of mucus from the lungs to identify the causative organism • Differentials: Helps differentiate bacterial pneumonia from viral or fungal infections Arterial Blood Gas (ABG): • Purpose: To measure oxygen and carbon dioxide levels in the blood, providing information about lung function • Differentials: Useful in assessing respiratory failure, which can occur in severe pneumonia, COPD exacerbations, and pulmonary embolism CT Scan: • Purpose: To obtain a more detailed image of the lungs if the chest X-ray is inconclusive or if complications are suspected • Differentials: Can help identify lung abscesses, pleural effusions, and other conditions that may mimic pneumonia Bronchoscopy: • Purpose: To directly visualize the airways and collect samples from the lungs for further analysis • Differentials: Useful in cases where the diagnosis is unclear or if there is suspicion of foreign body aspiration or malignancy Additional Testing Electrocardiogram (ECG): • Purpose: To rule out cardiac causes of chest pain and shortness of breath, such as myocardial infarction D-dimer Test: • Purpose: To rule out pulmonary embolism in patients with respiratory symptoms Procalcitonin Levels: • Purpose: To help differentiate bacterial pneumonia from other causes of inflammation, as elevated levels are more specific to bacterial infections (Vaughn, Dickson, & Horowitz, 2024)

5. Diagnosis

5.1. Primary Diagnosis Pneumonia

5.1.1. Medications (Drugs.com, 2025): Antibiotics: Amoxicillin, Azithromycin, Levofloxacin Antiviral Medications: Oseltamivir (Tamiflu) for influenza-related pneumonia Antifungal Medications: Fluconazole, Itraconazole Cough Suppressant: Dextromethorphan Referrals Pulmonologist: Infectious Disease Specialist: Inpatient Admission: Severe cases may require hospitalization for intravenous antibiotics, fluids, and oxygen therapy. Difficulty breathing, low oxygen levels, high fever, or significant comorbidities Self-Care: Rest, hydration, cough, deep breath, and changing position often. Acetaminophen or ibuprofen to reduce fever and alleviate pain and supplemental at home updraft/oxygen if needed. (American Lung Association, 2024)

5.2. Potential Diagnoses

5.2.1. Respiratory • Bronchitis: Inflammation of the bronchial tubes, often presenting with a persistent cough, mucus production, and chest discomfort • Chronic Obstructive Pulmonary Disease (COPD): Includes chronic bronchitis and emphysema, characterized by chronic cough, shortness of breath, and wheezing • Asthma: Chronic inflammatory disease of the airways, leading to wheezing, coughing, and shortness of breath • Tuberculosis: A bacterial infection that primarily affects the lungs, causing a persistent cough, weight loss, night sweats, and fever Cardiovascular • Congestive Heart Failure: Can cause fluid buildup in the lungs (pulmonary edema), leading to symptoms like shortness of breath, cough, and fatigue Infectious Diseases • Influenza: Viral infection that can cause fever, cough, body aches, and fatigue, sometimes leading to secondary bacterial pneumonia • COVID-19: Viral infection with symptoms including fever, cough, shortness of breath, and fatigue, which can progress to pneumonia Other (“Zebra” diagnoses) • Pulmonary Embolism: A blood clot in the lungs that can cause sudden shortness of breath, chest pain, and cough • Lung Cancer: Can present with a persistent cough, chest pain, and weight loss • Interstitial Lung Disease: A group of disorders causing scarring of lung tissue, leading to chronic cough and shortness of breath (American Family Physician, 2020)

5.2.1.1. References: (at least 2 research articles within 5 years) American Family Physician (2020) Community-acquired pheumonia: Updated recommendations from the ATS and IDSA. 102(2): 121-124. https://www.aafp.org/pubs/afp/issues/2020/0715/p121.html American Lung Association (2024) Pneumonia treatment and recovery. ALA Website. https://www.lung.org/lung-health-diseases/lung-disease-lookup/pneumonia/treatment-and-recovery Drugs.com (2025) Medications for pneumonia. Drugs.com: Know More. Be Sure. https://www.lung.org/lung-health-diseases/lung-disease-lookup/pneumonia/treatment-and-recovery Mayo Clinic (2020) Pneumonia: Diagnosis and treatment. https://www.mayoclinic.org/diseases-conditions/pneumonia/diagnosis-treatment/drc-20354210 National Heart, Lung, and Blood Institute (2022) Pneumonia: Diagnosis. NIH Website. https://www.nhlbi.nih.gov/health/pneumonia/diagnosis Vaughn, V.M., Dickson, R.P. & Horowitz, J.K. (2024) Community acquired pneumonia: A review. JAMA, 332(15): 1282-1295. doi:10.1001/jama.2024.14796