CHAPTER 22
OBSTRUCTIVE PULMONARY DISORDERS
OBSTRUCTIVE PULMONARY DISORDERS
• Manifested by increased resistance to airflow• Classifications• Obstruction from conditions in the wall of the
lumen• Obstruction resulting from increasing pressure
around the outside of the airway lumen • Obstruction of the airway lumen
OBSTRUCTION FROM CONDITIONS IN THE WALL OF THE LUMEN
Asthma• Etiology• Airway obstruction that is reversible (not
completely in some patients)• Airway inflammation• Increased airway responsiveness to a variety of
stimuli
OBSTRUCTION FROM CONDITIONS IN THE WALL OF THE LUMEN
(CONT.)Asthma• Statistics• Occurs in 5% to 12% of U.S. population• Most common chronic disease of children• High-risk populations• African Americans• Inner-city dwellers• Premature/low-birth-weight children
OBSTRUCTION FROM CONDITIONS IN THE WALL OF THE LUMEN
(CONT.)Asthma• Predisposing factors• Genetic for atopy and structural (smaller airways)• Chromosomes 5, 11, 14
• History of hay fever, eczema• Family history• Positive skin test reactions to allergens
OBSTRUCTION FROM CONDITIONS IN THE WALL OF THE LUMEN
(CONT.)Asthma• Extrinsic (allergic)• 1/3 to ½ of asthma cases• An IgE-mediated response is common• Clinical manifestations• Elevated IgE levels• Allergic rhinitis• Eczema• Positive family history of allergy• Attacks associated with seasonal, environmental or
occupational exposure
OBSTRUCTION FROM CONDITIONS IN THE WALL OF THE LUMEN
(CONT.)Asthma• Extrinsic• Mechanism of action• Immediate phase
• Initiated by exposure to specific antigen that has previously sensitized mast cells in airway mucosa
• Antigen reacts with antibody on surface of mast cell • Mast cell releases packets of chemical mediator
substances
OBSTRUCTION FROM CONDITIONS IN THE WALL OF THE LUMEN
(CONT.)Asthma• Extrinsic• Mechanism of action• Chemical mediators released
• Histamine• Slow-reacting substances of anaphylaxis (leukotrienes)• Prostaglandins• Bradykinins• Eosinophilic chemotactic factor• Serotonin
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Asthma• Extrinsic• Mechanism of action• Normal respiratory epithelium is denuded and
replaced by goblet cells• Alterations in epithelial integrity
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Asthma• Extrinsic• Mechanism of action• Increased microvascular permeability
• Mucosal edema• Inflammatory exudates• Bronchoconstriction• Leakage
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Asthma• Extrinsic • Mechanism of action• Late phase
• Arrival of recruited leukocytes signals initiation• More mediator release causes damage to epithelium
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Asthma• Extrinsic • Mechanism of action• Epithelial damage
• Hypertrophied smooth muscle• Edema• Mucous gland hypertrophy• Mucus in lumen
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Asthma• Inflammation of airway• Causes• Acute bronchospasm (bronchoconstriction)• Mucosal edema• Mucous plug formation• Airway wall remodeling
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Asthma• Pathogenesis• Immunohistopathologic features• Denudation of airway epithelium• Collagen deposition beneath the basement
membrane• Edema• Mast cell activation• Inflammatory cell infiltration by neutrophils,
eosinophils, and lymphocytes
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Asthma• Common symptoms• Wheezing• Feeling of tightness of chest• Dyspnea• Cough (dry or productive)• Increased sputum production (thick, tenacious,
scant, and viscid
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Asthma• Symptoms of severe attack• Use of accessory muscles of respiration• Intercostal retractions• Distant breath sounds with inspiratory wheezing• Orthopnea• Agitation• Tachypnea• Tachycardia
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Asthma• Diagnosis• Physical findings• Cough• Wheezing• Hyperinflated chest• Decreased breath sounds
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Asthma• Diagnosis• Radiographic finding• Hyperinflation with flattening of the diaphragm
• Sputum examination• Charcot-Leyden crystals (formed from crystallized
enzymes from eosinophilic membranes)• Eosinophils• Curschmann spirals (mucous casts of bronchioles)
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Asthma• Diagnosis• Pulmonary function tests• Forced expiratory volumes decrease• Peak expiratory flow rate (PEFR)
• Determines index of airway function• FEV1 measured over 1 second• FVC• Ratio of FEV1/FVC before and after administration of
short-acting bronchodilator • Obstruction indicated by FEV1/FVC <75%
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Asthma• Diagnosis• ABG• Normal during mild attack• Respiratory alkalosis and hypoxemia as
bronchospasm increases in intensity• PaCO2 elevation
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Asthma• Diagnosis • Skin testing • Young patients with extrinsic asthma
• Bronchial provocation testing• Test with histamine or methacholine
• CBC• Elevated WBCs • Elevated eosinophils
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Asthma• Treatment• Avoid triggers• Environmental control • Removal of allergens• Air purifiers• Air conditioners
• Preventive therapy• Desensitization (allergen specific immunotherapy)
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Asthma• Treatment• Medications• O2 therapy• Small-volume nebulizers• B2 agonists• Corticosteroids• Leukotriene modifiers• Mast cell inhibitors
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Acute Bronchitis• Etiology• Acute inflammation of the trachea and bronchi• Causes• Viral
• Influenza virus A or B• Parainfluenza virus• Respiratory syncytial virus• Coronavirus• Rhinovirus• Coxsackievirus• Adenovirus
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Acute Bronchitis• Etiology • Causes• Nonviral
• Streptococcus pneumoniae• Haemophilus influenzae• Mycoplasma• Moraxella• Chlamydia pneumoniae
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Acute Bronchitis• Etiology • Causes • Heat• Smoke inhalation• Inhalation of irritant chemicals• Allergic reactions
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Acute Bronchitis• Pathogenesis• Airways become inflamed and narrowed from
capillary dilation• Swelling from exudation of fluid• Infiltration with inflammatory cells increased
mucus production• Loss of ciliary function• Loss of portions of the ciliated epithelium
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Acute Bronchitis• Clinical manifestations• Cough (productive or nonproductive)• Low-grade fever• Substernal chest discomfort• Sore throat• Postnasal drip• Fatigue
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Acute Bronchitis• Diagnosis• Clinical presentation• Chest x-ray to distinguish acute bronchitis from
pneumonia
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Acute Bronchitis• Treatment• Antibiotic therapy (bacterial)• Codeine-containing medications (for cough)• Increase fluid intake• Avoid smoke• Use a vaporizer in bedroom
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Chronic Bronchitis• Etiology• Type B COPD, “blue bloater”• Chronic or recurrent productive cough >3 months
>2+ successive years• Persistent, irreversible• Typical patient is overweight (1:2 male to female
ratio)• >30-40 years• Commonly associated with emphysema
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Chronic Bronchitis• Cause• Cigarette smoking (90%)• Repeated airway infections• Genetic predisposition• Inhalation of physical or chemical irritants
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Chronic Bronchitis• Pathogenesis• Chronic inflammation and swelling of the bronchial
mucosa resulting in scarring• Elevated IL8 levels recruit neutrophil activation• Elevated CD8 T-lymphocytes• Extend into surrounding alveoli• Prevent proper oxygenation and potentiate airway
obstruction
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Chronic Bronchitis• Pathogenesis• Hyperplasia of bronchial mucous gland/goblet
cells• Increased mucus production• Mucus combines with purulent exudate (bronchial
plugs) to form mucous plug
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Chronic Bronchitis• Pathogenesis • Increased bronchial wall thickness• Resistance increases work of breathing• Increased O2 demands• Produce ventilation-perfusion mismatch with
hypoxemia and hypercarbia• Increases pulmonary artery resistance
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)
OBSTRUCTION FROM CONDITIONS IN THE WALL OF
THE LUMEN (CONT.)Chronic Bronchitis• Pathogenesis• Pulmonary hypertension• Inflammation in bronchial walls with vasoconstriction
of pulmonary blood vessels and pulmonary arteries• Right-sided heart failure may occur r/t high
pulmonary resistance
OBSTRUCTION CONDITIONS IN THE WALL FROM OF THE
LUMEN (CONT.)Chronic Bronchitis• Clinical manifestations• SOB on exertion • Excessive sputum• Chronic cough (more severe in mornings)• Evidence of excess body fluids (edema,
hypervolemia)• Cyanosis (late sign)
OBSTRUCTION CONDITIONS IN THE WALL FROM OF THE
LUMEN (CONT.)
OBSTRUCTION CONDITIONS IN THE WALL FROM OF THE
LUMEN (CONT.)Chronic Bronchitis• Diagnosis• Chest x-ray• Increased bronchial vascular markings• Congested lung fields• Enlarged horizontal cardiac silhouette• Evidence of previous pulmonary infection
OBSTRUCTION CONDITIONS IN THE WALL FROM OF THE
LUMEN (CONT.)Chronic Bronchitis• Diagnosis• Pulmonary function tests• Normal total lung capacity (TLC)• Increased residual volume (RV)• Decreased FEV1
OBSTRUCTION CONDITIONS IN THE WALL FROM OF THE
LUMEN (CONT.)Chronic Bronchitis• Diagnosis • Arterial blood gas (ABG)• Elevated PaCO2• Decreased PO2• Develop early in disease process
OBSTRUCTION CONDITIONS IN THE WALL FROM OF THE
LUMEN (CONT.)Chronic Bronchitis• Diagnosis• ECG• Atrial arrhythmias• Evidence of right ventricular hypertrophy
• Secondary polycythemia• R/t continuous or nocturnal hypoxemia
OBSTRUCTION CONDITIONS IN THE WALL FROM OF THE
LUMEN (CONT.)Chronic Bronchitis• Treatment• Medications• Inhaled short-acting B2 agonists• Inhaled anticholinergic bronchodilators• Cough suppressants• Antimicrobial agents (bacterial infections)• Inhaled/oral corticosteroids• Theophylline products
OBSTRUCTION CONDITIONS IN THE WALL FROM OF THE
LUMEN (CONT.)Chronic Bronchitis• Treatment• Low-dose O2 therapy• Patients with PaO2 levels <55 mm Hg
OBSTRUCTION CONDITIONS IN THE WALL FROM OF THE
LUMEN (CONT.)Chronic Bronchitis• Management• Smoking cessation• Bronchodilator therapy• Reduction to exposure of irritants• Adequate rest• Proper hydration• Physical reconditioning• Treadmill/stationary bike• Alternating rest and exercise
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
Emphysema• Etiology• Type A COPD• “Pink puffer”• Young to middle-age adults <50 years
(uncommon)• Hereditary low α1-antitrypsin activity in lung
• >50 years (develops over time)
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)Emphysema• Etiology• Causes• Smoking >70 pack/year• Air pollution• Certain occupations (mining, welding, working with or
near asbestos)• α1-Antitrypsin deficiency
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)Emphysema• Etiology• Smoking causes alveolar damage• Inflammation in lung tissue leading to release of
proteolytic enzymes• Inactivates α1-antitrypsin (protects lung parenchyma)
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)Emphysema• Pathogenesis• Release of proteolytic enzymes from inflammatory
cells (neutrophils, macrophages) leading to alveolar damage
• Reduction in pulmonary capillary bed• Exchange of O2 and CO2 between alveolar and
capillary blood impaired
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)Emphysema• Pathogenesis• Loss of elastic tissue in lung• Results in decrease in size of smaller bronchioles• Results in loss of radial traction (holds airway open)
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)Emphysema• Classifications• Centriacinar (centrilobular)• Associated with chronic bronchitis, emphysema• Destroys respiratory bronchioles
• Panacinar (panlobular)• Destroys the alveoli
• Paraseptal• Affects the peripheral lobules
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)Emphysema• Clinical manifestations• Progressive, exertional dyspnea• Increased SOB for past 3-4 years• Thin • R/t increased caloric expenditure and decreased
ability to consume adequate calories• Use of accessory muscles• Pursed-lip breathing• Cough (minimal or absent)
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)Emphysema• Diagnosis• Patient history and physical finding• Thin, wasted individual hunched forward• Barrel chest• Digital clubbing• Decreased breath sounds, lack of crackles and
rhonchi with prolonged expiration• Decreased heart sounds• Decreased diaphragmatic excursion
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)Emphysema• Diagnosis • Pulmonary function tests (PFTs)• Increased functional residual capacity• Increased RV• Increased TLC• Decreased FEV• Decreased FVC
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)Emphysema• Diagnosis• Chest x-ray• Hyperventilation• Low, flat diaphragm• Presence of blebs or bullae• Narrow mediastinum• Normal or small “vertical” heart
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)Emphysema• Diagnosis• ABG• Mild increase in PaO2• Normal PaCO2 (elevated in late stages)
• ECG• Normal, show tall P waves• Sinus tachycardia• Supraventricular arrhythmias• Ventricular irregularities
OBSTRUCTION RELATED TO LOSS OF LUNG PARENCHYMA
(CONT.)Emphysema• Treatment• O2 therapy• Medications• Inhaled short-acting B2 agonists• Inhaled anticholinergic bronchodilators• Cough suppressants• Antimicrobial agents (infections)• Inhaled/oral corticosteroids• Theophylline products
OBSTRUCTION OF AIRWAY LUMEN
Bronchiectasis• Etiology• Dilation of bronchial wall• Obstructive and suppurative (pus-forming)
disorder• Increased risk in children• Acquired
• Rare• Congenital
• 50% associated with cystic fibrosis
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Bronchiectasis• Classifications• According to bronchial shape• Saccular
• Cavity-like dilatations• Cylindrical• Fusiform
• Combination of saccular and cylindrical
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Bronchiectasis• Pathogenesis• Recurrent infection and infection of bronchial walls
leads to persistent dilation• Inflammation results in destruction of walls• Destructive process leads to loss of ciliated
epithelium• Transforms to squamous cell and pus formation• Leads to obstruction
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Bronchiectasis• Clinical manifestations• Chronic, productive cough • Purulent, foul-smelling, green, or yellow sputum• Hemoptysis• Fever, night sweats• Moist crackles including bases, rhonchi• Halitosis (bad breath)• Skin pallor• Digital clubbing (infrequent)
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Bronchiectasis• Clubbing• Caused by prolonged, decreased oxygenation• Associated with lymphocytic extravasation,
increased vascularity, and edema• Severity parallels the severity of disease
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Bronchiectasis• Complications• Malnutrition• Recurrent pneumonia• Right ventricular failure• Secondary visceral abscesses
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Bronchiectasis• Diagnosis• History of chronic, productive cough• Chest x-ray• Small cysts, bronchial wall thickening, increased
bronchial markings• PFTs• Decreased airflow and vital capacity
• ABG• Decreased PaO2, Increased PaCO2
• CT• Best choice for diagnosis
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Bronchiectasis• Treatment• Antibiotic therapy• Bronchodilators• Vigorous chest percussion and postural drainage• Proper hydration and nutrition• Bronchoscopy (if severe)• Surgical removal (if severe)
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Bronchiolitis• Widespread inflammation of bronchioles
due to infectious agents• Occasionally related to allergic reactions• Occurs winter to spring• Children <2 years• Adults • Smoking, toxic fumes, immunosuppression
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Bronchiolitis• Common organisms• Viral• RSV, influenzavirus (A, B, C)
• Bacterial• H. influenzae, pneumococci, hemolytic streptococci,
mycoplasma, chlamydia, Pneumocystis jiroveci
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Bronchiolitis• Pathogenesis• Proliferation and necrosis of bronchiolar
epithelium• Production of thick, tenacious mucus• Airway obstruction• Atelectasis• Hyperinflation
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Bronchiolitis• Pathogenesis• Possible mechanisms of airway obstruction• Development of inflammatory exudate• Release of chemical mediators• Inflammation• Goblet cell metaplasia• Increased bronchial muscle mass
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Bronchiolitis• Clinical manifestations• Severity and course range from mild-fatal• Wheezing r/t bronchospasm• Crackles• Decreased breath sounds• Retractions• Increased sputum• Dyspnea• Tachypnea• Low-grade fever
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Bronchiolitis• Diagnosis• Elevated WBC• Chest x-ray• Enlarged air sacs, interstitial infiltrates, atelectasis,
severe hyperinflation• PFT• Severe obstruction to airflow
• Nasal swab
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Bronchiolitis• Treatment• Adequate oxygenation• Bronchodilator agents• Corticosteroids• Sedation (anxiety)• Hydration, administration of medications• Antiviral/antibiotics• Smoking cessation
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Cystic Fibrosis• Etiology• Autosomal recessive disorder of exocrine glands• Dysfunction of CFTR gene (60%-75% of patients)
• 1:2000-3000 Caucasian births• >18 years (35%)• Affects pancreas, intestinal tract, sweat glands,
lungs, infertility (male)• Classified as Airflow or suppurative (pus-forming)
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Cystic Fibrosis• Clinical manifestations• History of cough in young adult or child• Thick, tenacious sputum• Recurrent pulmonary infections• Recurrent episodes of bronchitis
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Cystic Fibrosis• Clinical manifestations• Physical findings• Digital clubbing (late) • Dyspnea, tachypnea• Sternal retractions• Unequal breath sounds• Moist basilar crackles and rhonchi• Barrel chest hyperresonant to percussion
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Cystic Fibrosis• Clinical manifestations• Nutritional assessment• Depleted fat stores• Steatorrhea (fatty stools)• Anorexia• Decreased growth rate in children (wt, ht, head circ)• Decreased mid-arm indices
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Cystic Fibrosis• Diagnosis• ABG• PFT• Decreased VC, airflow, TV• Increased airway resistance, functional residual
capacity• Sputum C&S• Chest x-ray• Patchy atelectasis, bronchiectasis, obstructive
emphysema, cystic lung fields, peribronchial thickening
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Cystic Fibrosis• Diagnosis • 72-hour stool collection• Determine fat absorption and fecal fat excretion
• Sweat test (pilocarpine iontophoresis)• Elevated Na, Cl levels• 98% have levels >60 mEq/L (children) >80 mEq/L
(adult)• Genetic testing• Genetic marker AF-508 confirms diagnosis
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Cystic Fibrosis• Treatment• Postural drainage and chest physiotherapy
(priority)• Medications• Bronchodilators• High dose antibiotics (bacterial infections)• Influenza vaccine
• Heart-lung or lung transplant
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Cystic Fibrosis• Treatment• Nutritional therapy• Unrestricted fat consumption
• 30% of caloric intake• High protein• Vitamin supplements• Pancreatic enzymes• Intake of 150% normal caloric intake
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Acute Tracheobronchial Obstruction• Etiology• Causes• Aspiration of foreign body (most often in left lung)• Malpositioned endotracheal tube• Laryngospasm• Epiglottitis• Trauma• Swelling (smoke inhalation)• Postsurgical blood clot• Compression of bronchus/trache (tumor, enlarged
lymph nodes
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Acute Tracheobronchial Obstruction• Clinical manifestations• Partial obstruction• Stridor• Sternal and intercostal retractions• Wheezing• Nasal flaring• Tachypnea, dyspnea• Tachycardia• Use of accessory muscles
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Acute Tracheobronchial Obstruction• Clinical manifestations• Complete obstruction• No air movement heard with auscultation (complete
obstruction)• Inability to talk• Tachycardia• Cyanosis• Rapid progression to unconsciousness
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Acute Tracheobronchial Obstruction• Diagnosis• Based on clinical features• ABG• Hypoxemia, hypercarbia
• Chest x-ray• Location of obstruction
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Acute Tracheobronchial Obstruction• Treatment• Open obstructed airway as soon as possible• Heimlich to expel foreign body• Suction• Emergency tracheostomy (obstruction in
subglottic region or above)
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Epiglottitis• Etiology• Rapidly, progressive cellulitis of epiglottis and
adjacent soft tissues• Subtype of croup• Children 2 to 4 years• Common organisms• Pneumococci, streptococci, staphylococci
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Epiglottitis• Pathogenesis• Infecting agent localizes in epiglottis and
pharyngeal structures• Causes rapid and potentially fatal inflammation • Swelling • Airway obstruction
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Epiglottitis• Clinical manifestations• Drooling• Dysphagia, dysphonia• Rapid onset of fever• Inspiratory stridor and retractions• Oropharynx edematous and cherry red• Child sits in “sniffing dog” position• Provides best airway patency
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Epiglottitis• Diagnosis• Direct or fiberoptic visualization of epiglottis• Lateral neck x-ray• Classic “thumbprint sign”
• CBC• Leukocytosis with shift to left
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Epiglottitis• Treatment• True medical emergency• May necessitate intubation• Antibiotic therapy• Preventative• Hib vaccine
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Croup Syndrome• Etiology• A number of acute, viral inflammatory diseases of
larynx, trachea, and bronchi• Laryngotracheobronchitis (viral croup)• Epiglottitis• Bacterial tracheitis
• Occurs in fall and early winter• Children 6 months to 3 years
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Croup Syndrome• Etiology• Causes• Parainfluenza virus type 2 and 3• RSV• Influenzavirus• Adenovirus• Mycoplasma pneumoniae
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Croup Syndrome• Pathogenesis• Viral agent of subglottic area• Infectious agent causes inflammation along entire
airway• Leads to edema in subglottic area
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Croup Syndrome• Clinical manifestations• History of upper respiratory infection or cold• Barking cough with stridor• Low-grade fever (may be absent)• Severe cases• Stridor at rest• Retractions• Cyanosis
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Croup Syndrome• Diagnosis• Clinical signs and symptoms• Lateral neck films• Subglottic narrowing and normal epiglottis
• Laryngoscopy• Confirm presence or rule out epiglottitis
OBSTRUCTION OF AIRWAY LUMEN (CONT.)
Croup Syndrome• Treatment• Mist therapy• Oral hydration• Avoidance of stimulation• O2 therapy, pulse oximetry (hospitalized)• Nebulized epinephrine (relieves airway
obstruction)• Endotracheal intubation (respiratory failure)
DIAGNOSTIC TESTSPulmonary Function Testing (PFT)• Demonstrates obstruction of airflow in
lungs• Spirometry• Determines severity and diagnosis of COPD• Patient inhales deeply and exhales as quickly as
possible until maximal air is exhaled
DIAGNOSTIC TESTS (CONT.)Pulmonary Function Testing (PFT)• Spirometry• Forced vital capacity• Total volume of air exhaled• Time required for exhaling the air is also measured
• Forced expiratory volume in 1 second• Volume exhaled in 1st second is reliable and index of
obstructive airway disease
DIAGNOSTIC TESTS (CONT.)
DIAGNOSTIC TESTS (CONT.)Pulmonary Function Testing (PFT)• Spirometry• Airflow obstruction• FEV1/FVC ratio >75%
• No significant obstruction • FEV1/FVC ratio between 60% and 70%
• Mild obstruction• FEV1/FVC ratio 50% to 60%
• Moderate obstruction• FEV1/FVC ratio <50%
• Severe obstruction
DIAGNOSTIC TESTS (CONT.)
DIAGNOSTIC TESTS (CONT.)Spirometry• Inhaled bronchodilator given, repeat test in
15-20 minutes• Positive bronchodilator response• FEV1 improves >15% = positive bronchodilator
response• Partially reversible bronchospasm of smooth muscle
(asthma, asthmatic bronchitis)
DIAGNOSTIC TESTS (CONT.)Spirometry• Diffusion capacity• Measures ability of alveolar gases to diffuse into
capillary blood• Valuable for determining fibrosis or destruction of
membrane
DIAGNOSTIC TESTS (CONT.)Spirometry• Total lung capacity• Normal RV/TLC 30% to 35%• Breathing mixtures of inert gas (helium)• Volume composed of FVC and RV (residual volume• Volume voluntarily exhaled all of the air from lungs
• ABG• Assesses oxygenation and acid-base status
DIAGNOSTIC TESTS (CONT.)
DIAGNOSTIC TESTS (CONT.)Spirometry• Diagnosis of obstructive disorder• Decreased FEV1• Low FEV1/FVC ratio (<70%)• Improvement in FEV1 after use of bronchodilator
(asthma)• Increased residual volume• Increased functional residual capacity
DIAGNOSTIC TESTS (CONT.)Bronchial Provocation Tests• Induction of bronchospasm by inhalation of
various agents• Series of ventilations administered• Identify hyper-reactive airways and identify source
of bronchospasm• Done only with emergency support services• Hyperactivity = fall >20%