Pathophysiological Concepts Chapter 28: Developmental Alterations of Pulmonary Function

Chest Trauma

• Open Pneumothorax: Air accumulates in the pleural space due to an open chest wound, leading to lung collapse.
• Tension Pneumothorax: Life-threatening condition where air is trapped under positive pressure, displacing mediastinal structures such as the heart and trachea, resulting in tracheal deviation.

Pneumothorax: Manifestations, Diagnosis & Treatment

• Clinical Manifestations: Includes sudden pleural pain, tachypnea, dyspnea, decreased breath sounds, hyperresonance on percussion, severe hypoxemia, tracheal deviation (in tension), and hypotension (in tension).
• Diagnosis: Utilizes chest X-ray, ultrasound, and CT scans for confirmation.
• Treatment Options: May involve aspiration, chest tube insertion to a water-seal drainage system with suction, and removal of the chest tube after resolution.

Pleural Effusion

• Definition: Accumulation of fluid in the pleural space; types include empyema (pus), hemothorax (blood), and chylothorax (chyle).
• Clinical Manifestations: Symptoms include dyspnea, pleural pain, decreased breath sounds, or pleural friction rub.
• Diagnostic Tests: Chest X-ray and thoracentesis for fluid testing.
• Treatment: Chest tube drainage for large effusions and symptom management.

Empyema

• Definition: Infected pleural effusion characterized by pus, commonly caused by bacteria like Staphylococcus aureus and E. coli.
• Etiology: Often a complication of pneumonia, surgery, trauma, or tumors.

Signs & Symptoms of Pulmonary Disease

• Dyspnea: Experience of breathing discomfort, including breathlessness and labored breathing.
• Orthopnea: Dyspnea occurring when lying flat, associated with heart failure.
• Paroxysmal Nocturnal Dyspnea: Sudden nighttime breathlessness requiring sitting or standing to breathe.

Cough and Sputum

• Cough: Protective reflex to clear airways; can be acute or chronic.
• Abnormal Sputum: Changes indicate disease progression; sputum samples help identify microorganisms.
• Hemoptysis: Presence of blood in sputum, usually diagnosed with bronchoscopy and chest CT.

Abnormal Breathing Patterns

• Kussmaul Respirations: Increased rate and depth, often from metabolic acidosis or exercise.
• Labored Breathing: Increased work of breathing typically due to obstruction.
• Restricted Breathing: Resulting from lung stiffening leading to decreased lung compliance.
• Cheyne-Stokes Respiration: Cycles of deep and shallow breaths, may indicate brain stem issues.

Hypoventilation and Hyperventilation

• Hypoventilation: Inadequate ventilation causing respiratory acidosis; diagnosed through ABG.
• Hyperventilation: Excessive ventilation leading to respiratory alkalosis; often found in anxiety or pain.

Gas Exchange Issues: V/Q Mismatch

• Low V/Q: Indicates shunting due to inadequate ventilation in well-perfused areas (e.g., atelectasis).
• High V/Q: Indicates dead space due to inadequate perfusion in well-ventilated areas (e.g., pulmonary embolism).

Acute Respiratory Failure

• Definition: Inadequate gas exchange due to lung or airway injury, indirect conditions (like brain/spinal cord injury), or surgery.
• Causes: Include trauma, opioid overdose, and pre-existing conditions.
• Treatment Strategies: Depends on hypercapnia (ventilatory support) or hypoxemia (supplemental oxygen), with Narcan for overdose cases.

Postoperative Respiratory Failure

• Risks: Commonly associated with major surgery; includes complications like atelectasis, pneumonia, and pulmonary emboli.
• Prevention: Emphasizes turning, deep-breathing exercises, and early ambulation.

Chest Wall Restriction

• Causes: Resulting from deformities, trauma, or obesity, leading to increased work of breathing and hypoventilation.
• Flail Chest: Consequence of fractured consecutive ribs, leading to paradoxical chest movements.
• Treatment: Focuses on symptom support and mechanical ventilation if severe.

Pneumothorax Types

• Primary Pneumothorax: Sudden onset without apparent cause, usually benign.
• Secondary Pneumothorax: Results from underlying lung conditions.

Pulmonary Fibrosis

• Definition: Excessive connective tissue in the lung, leading to scarring; often idiopathic.
• Clinical Manifestations: Dyspnea on exertion, inspiratory crackles.
• Diagnostic Tests: Include pulmonary function tests, CT scans, and lung biopsy.
• Treatment Options: Include oxygen therapy, corticosteroids, cytotoxic medications, or lung transplant.

Pulmonary Edema

• Definition: Excess fluid in the lung; most commonly caused by left-sided heart disease.
• Clinical Manifestations: Dyspnea, hypoxemia, increased work of breathing, and frothy sputum in severe cases.
• Treatment Strategies: Varies based on underlying cause; treatments for heart failure include diuretics and oxygen therapy.

Acute Lung Injury / ARDS

• Definition: Serious condition of lung inflammation and injury, often due to sepsis or trauma.
• Phases: Progresses from inflammation to resolution and potential remodeling/fibrosis.
• Clinical Manifestations: Range from dyspnea and hyperventilation to organ dysfunction and hypoxemia.

Respiratory Tract Infections

• Upper Respiratory Tract Infections (URTI): Include common cold, pharyngitis, laryngitis.
• Lower Respiratory Tract Infections (LRTI): Primarily pneumonia, affecting vulnerable populations like the young, elderly, or immunocompromised.

Acute Bronchitis

• Definition: Inflammation of airways, typically viral and self-limiting.
• Clinical Manifestations: Similar to pneumonia, including fever and cough.
• Treatment: Rest, humidity, cough suppressants, and antibiotics if bacterial.

Pneumonia

• Definition: Infection of the lower respiratory tract from various pathogens including bacteria and viruses.
• Types: Classified as healthcare-associated, community-acquired, hospital-acquired, and ventilator-associated pneumonia.
• Clinical Manifestations: Includes fever, cough, malaise, and pleural pain.
• Diagnosis: Based on WBC count, chest X-ray, sputum/blood cultures.
• Prevention: Key focus in management strategies.