Alterations of Pulmonary Function: Signs and Symptoms of Pulmonary Disease

Alterations of Pulmonary Function

Introduction

This section covers the major signs and symptoms associated with pulmonary (lung) diseases, focusing on the physiological changes and clinical manifestations that help in diagnosis and management. Understanding these symptoms is essential for recognizing and treating respiratory disorders.

Signs and Symptoms of Pulmonary Disease

Dyspnea

Dyspnea is the subjective sensation of uncomfortable or difficult breathing. It is a common symptom in many pulmonary diseases and can vary in severity and presentation.

• Severe dyspnea:

  • Flaring of the nostrils

  • Use of accessory muscles of respiration (such as neck and chest muscles)

  • Retraction of the intercostal spaces (the spaces between the ribs are pulled inward)

• Dyspnea on exertion: Shortness of breath that occurs with physical activity.

• Orthopnea: Dyspnea that occurs when lying down, often relieved by sitting or standing up. Common in heart failure.

• Paroxysmal nocturnal dyspnea: Sudden episodes of shortness of breath at night, causing the person to awaken and need to sit or stand up to breathe comfortably.

Cough

Cough is a protective reflex that helps clear the airways by an explosive expiration. It is a common symptom in respiratory diseases.

• Acute cough: Resolves within 2–3 weeks.

• Chronic cough: Lasts longer than 3 weeks and may indicate chronic respiratory or cardiac disease.

Abnormal Sputum

Sputum is the mucus and other matter brought up from the lungs by coughing. Changes in the amount, consistency, color, and odor of sputum can provide important information about the progression of disease and the effectiveness of therapy.

Hemoptysis

Hemoptysis is the coughing up of blood or bloody secretions from the lower respiratory tract. It is a serious symptom that may indicate infection, malignancy, or vascular problems in the lungs.

Breathing Patterns

• Eupnea: Normal, unlabored breathing pattern.

• Abnormal breathing patterns: Adjustments made by the body to minimize the work of respiratory muscles. Examples include:

  • Kussmaul respirations (hyperpnea): Slightly increased ventilatory rate, very large tidal volume, and no expiratory pause. Often seen in metabolic acidosis (e.g., diabetic ketoacidosis).

  • Labored breathing: Increased work of breathing, often seen in airway obstruction.

Restricted Breathing

Occurs in disorders that stiffen the lungs or chest wall and decrease compliance, making it harder to expand the lungs.

Cheyne-Stokes Respirations

Characterized by alternating periods of deep and shallow breathing. Apnea (no breathing) lasts 15–60 seconds, followed by ventilations that increase in volume until a peak is reached, then decrease again to apnea. Seen in severe heart failure, stroke, or brain injury.

Hypoventilation and Hyperventilation

Hypoventilation	Hyperventilation
Alveolar ventilation is inadequate in relation to metabolic demands. Leads to respiratory acidosis from hypercapnia (increased CO2). Caused by alterations in pulmonary mechanics or neurologic control of breathing.	Alveolar ventilation exceeds metabolic demands. Leads to respiratory alkalosis from hypocapnia (decreased CO2). Caused by anxiety, head injury, or severe hypoxemia.

Key Equations:

• Respiratory acidosis: $CO_2 \uparrow \rightarrow pH \downarrow$

• Respiratory alkalosis: $CO_2 \downarrow \rightarrow pH \uparrow$

Summary Table: Common Signs and Symptoms of Pulmonary Disease

Symptom	Definition	Clinical Significance
Dyspnea	Subjective sensation of uncomfortable breathing	Indicates respiratory or cardiac dysfunction
Cough	Protective reflex to clear airways	Acute or chronic; may indicate infection or chronic disease
Hemoptysis	Coughing up blood	May indicate infection, malignancy, or vascular disorder
Abnormal sputum	Changes in mucus from lungs	Helps assess disease progression and therapy effectiveness
Abnormal breathing patterns	Altered rate, depth, or rhythm of breathing	Seen in various pulmonary and systemic diseases

Additional info: These notes are based on textbook slides and are suitable for college-level Anatomy & Physiology students studying respiratory system pathophysiology.