PANCE Blueprint Pulmonary (9%)

ReelDx Virtual Rounds (asthma)

Asthma is a chronic, reversible inflammatory airway disease characterized by episodic bronchoconstriction, airway hyperresponsiveness, and mucus production

• Common triggers include allergens, exercise, cold air, respiratory infections, and irritants like smoke or pollution
• Presents with episodic wheezing, cough (especially at night), chest tightness, and dyspnea
• Physical exam may show prolonged expiration, wheezing, and accessory muscle use during exacerbations

Diagnosis and Monitoring

• Monitor with peak flow
  • PFTs: Greater than 12% increase in FEV1 after bronchodilator therapy
  • FEV1 to FVC ratio <80% (reflects obstruction due to inflammation)
    • In asthma, since there is an obstruction (inflammation), you will have a decreased FEV1 and, therefore, a reduced FEV1 to FVC ratio
• In a patient with asthma, a chest X-ray may show hyperinflation (a flattened diaphragm and increased lung volume), peribronchial thickening, or atelectasis due to mucus plugging during an exacerbation.

Treatment Guidelines

Previously, asthma was labeled 'mild intermittent' or 'severe persistent,' but GINA now recommends a treatment-based approach (Step 1–5) based on both symptom control and exacerbation risk.

The Global Initiative for Asthma (GINA) strategy divides asthma treatment into two tracks for adults and adolescents:

• Track 1: The preferred treatment option is an as-needed combination of low-dose ICS-formoterol
• Track 2: An alternative option that uses SABA as the reliever, along with a separate preventer inhaler. This track may be used if ICS-formoterol is not available or if patients have no risk factors for exacerbations

Table 1: GINA Track 1

• Preferred initial treatment for most patients
• Suitable for patients who respond well to ICS and have a low risk of side effects

Table 2: GINA Track 2

• Alternative for patients concerned about ICS side effects, or if ICS + LABA isn't preferred
• Can also be used for quick relief of symptoms, streamlining treatment

Acute Treatment

• Oxygen, nebulized SABA, ipratropium bromide, and oral corticosteroids

Chronic obstructive pulmonary disease

Chronic Obstructive Pulmonary Disease (COPD) is a progressive, irreversible airway disease characterized by airflow limitation due to chronic bronchitis, emphysema, or both

• Chronic cough: Persistent cough for 3+ months/year for 2 years
• Sputum production: Lots of mucus, often daily
• Smokers: Mostly caused by smoking
• "Blue Bloaters": Cyanosis (blue) and edema (bloating) from low oxygen
• Stocky build: Often stocky, not always overweight
• Pneumonia: Frequent lung infections
• ↓ FEV1/FVC (<0.7): Obstructive pattern on spirometry
• Bronchial markings: Thickened airway walls on imaging
• ↑ Hemoglobin/Hematocrit: Higher due to low oxygen
• Crackles and wheezes: Lung sounds from mucus and narrowing

• Minimal cough/sputum, lots of shortness of breath: Less mucus, more lung damage
• "Pink Puffers": Pink skin, heavy breathing: Hyperventilation keeps oxygen up
• Smokers: Mostly caused by smoking: Smoking destroys alveoli
• Thin and underweight: Breathing burns calories
• Loss of lung markings on imaging: Fewer vessels from alveolar loss
• Hyperinflation and flattened diaphragm: Trapped air expands lungs
• Barrel chest: Chest widens from air trapping
• Small, thin-looking heart on X-ray: Lungs compress heart
• ↓ FEV1/FVC (<0.7): Airways collapse
• Bullae in lung tissue: Air pockets from damage
• Quiet breath sounds and long exhales: Less tissue, slow airflow
• Faint heart sounds: Lungs muffle heart
• Chronic hyperventilation, usually no CO2 buildup: Fast breathing clears CO2
• Normal HCT and Hb (unless end-stage with low oxygen): Oxygen stays normal

Chronic bronchitis is defined as a chronic cough that is productive of phlegm occurring on most days for 3 months of the year for two or more consecutive years without an otherwise defined acute cause

• Chronic Bronchitis = Blue Bloaters (2º to chronic hypoxia)
• Common in smokers (80% of COPD patients)
• Frequent cough and expectoration are typical (compared to emphysema)
• Stocky, overweight
• Increased HCT and Hb due to chronic hypoxemia

"The common organisms causing pneumonia in patients with COPD are Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Patients who smoke are often colonized with Haemophilus influenza."

DX:

Board bottom line: spirometry makes the diagnosis — a post-bronchodilator FEV1/FVC <0.70 — and GOLD 1–4 grades how severe.

• Diagnosis (spirometry): post-bronchodilator FEV1/FVC <0.70 = persistent airflow limitation that is not fully reversible (the key contrast with asthma)
• Severity — GOLD 1–4 by FEV1 % predicted (the “80–50–30” cutoffs): 1 mild ≥80 · 2 moderate 50–79 · 3 severe 30–49 · 4 very severe <30
• CXR: hyperinflation + flattened diaphragm (emphysema); increased bronchial markings (chronic bronchitis)
• Chronic hypoxia → ↑ Hgb/Hct; advanced disease → cor pulmonale (RVH, distended neck veins, hepatomegaly, edema)
• ↓ DLCO in emphysema (normal in chronic bronchitis); exam: prolonged expiration, wheezes/crackles, hyperresonant percussion in emphysema

TX:

Board pearl: only smoking cessation and long-term oxygen reduce mortality — everything else treats symptoms and exacerbations.

• Smoking cessation = the single most important step (slows lung-function decline; lowers mortality)
• Bronchodilators = backbone: short-acting albuterol (SABA) / ipratropium (SAMA) = rescue; long-acting LAMA (tiotropium) ± LABA = maintenance (ipratropium is short-acting, not a maintenance inhaler)
• Step up by GOLD group (A / B / E): A → one long-acting bronchodilator; B & E → LABA + LAMA; add ICS only if eosinophils ≥300 (avoid <100 — pneumonia risk)

GOLD A / B / E groups — initial maintenance therapy

• Long-term oxygen if resting SpO2 ≤88% → improves survival
• Prevent: pulmonary rehab + influenza, pneumococcal, COVID-19 vaccines
• Exacerbation = “ABC”: Antibiotics (↑ sputum purulence/volume) + Bronchodilators (SABA) + Corticosteroids (systemic, e.g., prednisone)
• Recurrent exacerbations: roflumilast (PDE-4 inhibitor; chronic-bronchitis phenotype, FEV1 <50%), chronic azithromycin, or dupilumab (eosinophilic/type 2)

Chest X-ray of chronic bronchitis showing increased bronchial markings and perivascular haziness from airway inflammation.

Emphysema is a condition in which air spaces are enlarged due to destruction of the alveolar septa

• The body's natural response to ↓ lung function is chronic hyperventilation, also known as Pink Puffers. CO2 Retainers - the body must increase ventilation to blow off CO2
• Minimal cough (compared to chronic bronchitis), quiet lungs
• Minimal sputum (compared to chronic bronchitis)
• Thin, underweight, and barrel-chested
• Normal HCT and Hb in most cases, unless end-stage disease leads to severe hypoxemia

DX:

• PFTs: FEV1/FVC ratio of less than 0.7
• Destruction of alveoli (air sacs) reduces lung elasticity. Without elastic recoil, airways collapse during exhalation, trapping air and blocking outflow. FEV1 decreases due to poor airflow, while FVC can be near normal or slightly reduced, yielding a ratio <0.7
• Chest X-ray shows hyperinflation, flattened diaphragm, reduced lung markings, bullae, and a small, thin-appearing heart
  • Parenchymal bullae and subpleural blebs are pathognomonic:
    • Bullae are larger air spaces (>1 cm) in the lung parenchyma, common in emphysema from merged, broken alveoli
    • Subpleural blebs are smaller air pockets (<1 cm) under the pleura, also from alveolar damage, but more superficial
• Normal hematocrit (HCT)
• Auscultation: Diminished breath/heart sounds
• Percussion: hyperresonance

TX: Management is the same as Chronic Bronchitis

• Ipratropium (also albuterol inhaler)
• O2
• Oral steroids
• Antibiotics (see Chronic Bronchitis)

Chest X-ray of bullous emphysema showing large bullae (air pockets from alveolar destruction) (arrow), hyperinflation, reduced lung markings, a small, thin appearing heart, and a flattened diaphragm.

Cystic fibrosis (CF) affects secretions — they become thick and sticky → block airways and ducts

• Etiology: Autosomal recessive CFTR gene mutation

Presentation:

• Pulmonary: chronic cough, recurrent infections (esp. Pseudomonas), bronchiectasis, nasal polyps
• GI: meconium ileus, pancreatic insufficiency, fat-soluble vitamin deficiencies, failure to thrive (FTT)
• Infertility in males due to congenital bilateral absence of the vas deferens

DX:

• Sweat chloride test (↑ chloride) + CFTR mutation
• CXR: hyperinflation, bronchial thickening, mucus plugging (see images)

TX:

• • Airway clearance: chest physiotherapy, mucolytics (e.g., dornase alfa)
  • Inhaled antibiotics, pancreatic enzymes
  • High-fat diet + fat-soluble vitamins (A, D, E, K)
  • CFTR modulators: ivacaftor, lumacaftor
  • Acute exacerbations: oral or IV antibiotics for Pseudomonas & Staph
  • Chronic suppression: inhaled tobramycin or aztreonam
  • Lung transplant for advanced disease

• Complications include respiratory failure, diabetes, cirrhosis, and pneumothorax

Meconium ileus in preterm twins revealing a novel cystic fibrosis mutation. Image by Department of Pediatrics, Albert-Ludwigs-University of Freiburg, Mathildenstrasse 1, D 79106 Freiburg, Germany. [email protected]. License: CC BY 2.0