Human Respiratory Diseases

Lung Diseases

Obstructive Diseases of the Lungs

Neonatal Respiratory Distress Syndrome (nRDS)

• Premature infants get this when their respiratory system is not well developed
• They lack surfactant and the system that produces it
• This causes poor O2 intake and possible collapsing of the lungs
• Can be treated by giving the infant surfactant until the system is developed on its own

Asthma

• Smooth muscles in airways are in spasm
• This obstructs the lungs function

Chronic Bronchitis

• The respiratory system is filled with mucus
• Inflammation and mucus obstruct the air flow into and out of the lung
• This inhibits the air intake of the lungs

Emphysema

• Destruction of the alveolar walls
• Decreased lung compliance = obstruction of gas exchange and decreased tidal volume of the lungs

Chronic Obstructive Pulmonary Disease (COPD)

• Obstructed airflow into and out of the lungs
• Caused by long term exposure to irritating gases and particulates
• Chronic bronchitis and emphysema lead to COPD

Cystic Fibrosis

• Decreased gas exchange caused by thick, dry mucus layer
• Caused by genetic mutations affecting chloride and water transport

Restrictive Diseases of the Lungs

Pulmonary Fibrosis

• Scar tissue caused by inhalation of pollution
• Decreases the compliance of the lungs (scar tissue is not stretchy --> poor elasticity)

Respiratory Disease Diagnostic & Treatment Strategies

Diagnosing Respiratory Disease

Pulmonary Function Tests

• Spirometry
• Patient breaths into a tube while performing breathing exercises to measure tidal volume, vital capacity and total lung capacity
• Peak Flow Meter Tests
• Not as accurate as spirometry
• Measures the volume of air that can be exhaled
• Challenge Tests
• If dealing with asthma, exercise or particulate exposure can be done in the presence of a doctor to see what is causing the bronchial spasms

Imaging Tests

• Chest X-rays
• The images can show obstructive and restrictive respiratory disease

• CT scans (Computed Tomography)
• The images can show obstructive and restrictive respiratory disease

• Bronchoscopy
• A small, flexible tube is put down the trachea to observe lung tissue through a camera and to take lung tissue samples

Treating Respiratory Disease

• Bronchodilators
• Medicine that encourages the bronchi to relax and open to allow more air through
• Used to treat obstructive respiratory disease
• Corticosteroids
• Decreases inflammation to open and relax bronchi
• Used to treat obstructive and restrictive respiratory disease
• Oxygen therapy
• Delivering high concentrations of oxygen to the lungs through tubes or a face mask
• Used to treat obstructive and restrictive respiratory disease

Drugs & Respiration

Alcohol & Respiration

• While drinking
• Alcohol is a type of sedative so decreases coughing and gagging reflexes
• Reducing these reflexes increases chance of bacteria, viruses, and dust entering your lungs
• Over a long period
• Increased incidence of pneumonia and acute respiratory distress syndrome
• Prolonged alcohol use alters the good bacteria in your mouth and throat, opening up a breeding ground for bad bacteria

Nicotine & Respiration

• Smoking tobacco
• Contains nicotine and additional harmful chemicals
• Causes irritation and swelling of the trachea and bronchi, and damages alveolar sacs
• Causes cancer, chronic bronchitis, emphysema and eventually chronic obstructive pulmonary disease
• Increased risk of lung cancer (even if nicotine is not inhaled through a cigarette)
• Nicotine reduces the protein elastin in the lungs
• Causes restrictive lung disease
• Nicotine affects the nervous system by telling the body to constrict the bronchi and cause rapid, shallow breathing

Marijuana & Respiration

• Smoking marijuana
• Contains the same harmful chemicals found in smoking pure tobacco
• Any inhalation of a burned substance is harmful to the lungs
• Causes acute bronchitis, chronic coughing, a lung/airway inflammation
• THC (the active ingredient that makes someone feel "high") is an immunosuppressive
• Studies suggest that long term marijuana use may increase risk of lung infections