Pulmonary pearls

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Obstructive Lung Disease:

PFTs show decrease FEV1/FVC and increased TLC

COPD: components of emphysema (destruction of alveolar walls) and chronic bronchitis (mucus plugging and inflammation of airways)

Risks: smoking, alpha 1 antitrypsin deficiency, environmental factors

Clinically: productive cough, dyspnea, tachypnea, possible hemoptysis

Dx: PFTs, CXR shows hyperinflation and flat diaphragms

Rx: STOP SMOKING, inhaled albuterol + ipratoprium, low dose steroids, O2 with chronic hypoxemia, and inhaled albuterol + ipratoprium + IV steroids + antibiotics for acute COPD exacerbation

Complications: exacerbations (usually infections), pulmonary HTN and cor pulmonale, polycythemia

Asthma: reversible airflow obstruction due to inflammation and hyperresponsiveness

Clinically: intermittent SOB, chest tightness, wheezing, cough usually within 30 mins of environmental trigger

Dx: peak expiratory flow rate for quick diagnosis in ER, PFTs show 12% increase in FEV1/FVC with albuterol (obstruction is reversible), ABG shows hypocarbia unless acute exacerbation is severe

Rx: inhaled B2 agonists, inhaled steroids

Bronchiectasis: impaired cilia action allows infection precipitating dilation and destruction of bronchioles

Causes: usually idiopathic, cystic fibrosis, immune deficiency

Clinically: chronic cough with foul mucopurulent sputum, dyspnea, hemoptysis, recurrent pneumonia

Dx: CT is diagnostic, PFTs will show obstructive pattern

Rx: Abx for exacerbations, chest physiotherapy, bronchodilators

Lung Cancer

Risks: smoking, asbestos, COPD

Clinically

Nonspecific sx: cough, hemoptysis, SOB, etc

Others: Horner’s syndrome, SIADH, hyperparathyroidism, etc and other paraneoplastics

Dx: CXR may detect, CT to stage, biopsy for definitive diagnosis

Small cell lung cancer

Essentially considered metastatic at presentation

Usually a central tumor

Rx: chemo and radiation, no surgery

Non-small cell lung cancer

Squamous cell: usually central

Adenocarcinoma: usually peripheral, seen in non-smokers

Large cell: usually peripheral

Rx: surgery is best if not metastatic, chemo and radiation as adjuncts

Pleural Disease

Pleural effusion

Transudative: CHF, cirrhosis, PE, nephritic syndrome

Exudative: pleural/serum protein > 0.5 + LDH > 0.6; pneumonia, malignancy, collagen vascular diseases

Clinical: DOA, PND, orthopnea, dullness to percussion, decreased breath sounds and tactile fremitus

Dx: CXR, CT, thoracocentesis

Rx: diuretics, sodium restriction for transudates, treat underlying cause for exudates; therapeutic thoracocentesis

Pneumothorax

Traumatic (chest tube, transthoracid needle) vs Spontaneous

Clinically: sudden onset ipsilateral chest pain, dyspnea, cough, decreased breath sounds and hyperresonance over affected side

Dx: CXR  midline shift towards affected side

Rx: chest tube

Tension: barotraumas, penetrating trauma

Clinically: hypotension, distended neck veins, decreased breath sounds and hyperresonance over affected side

Rx immediately: decompress with large bore needle or chest tube

CXR shows midline shift away from affected lung, but treat before CXR if tension pneumothorax suspected

Interstitial Lung Disease: restrictive lung disease PFTs with low diffusing capacity

Sarcoidosis

Clinically: Usually African-american <40yo with constitutional sx, dry cough, DOA, possible erythema nodosum, anterior uveitis, arrhythmias, arthralgias, bell’s palsy, etc

Dx: Bilateral hilar adenopathy on CXR, elevated ACE, non caseating granuloma on biopsy

Rx: systemic corticosteroids, methotrexate

Wegener’s granulomatosis: necrotizing granulomatous vasculitis of lung and kidney

Clinically: hemoptysis, resp infections, glomerulonephritis

Dx, c-anca, gold standard is biopsy

Rx: immunosuppressive therapy and glucocorticoids

Churg-Strauss: granulomatous vasculitis in asthma patients

Clinically: rash, asthma, sinusitis

Dx: eosinophilia, p-anca, but gold standard is biopsy

Rx: systemic glucocorticoids

Coal worker’s pneumoconiosis: ranges from asymptomatic dust deposition in lungs to development of interstitial fibrosis and significant restrictive disease

Asbestosis

Diffuse interstitial fibrosis of insidious onset; prediliction for lower lobes

Increased risk for bronchogenic carcinoma (synergistic with smoking)

Increased risk for mesothelioma

Goodpasture’s syndrome

Auto IgG deposition against glomerular/alveolar basement membrane

Clinically: hemoptysis, glomerulonephritis, dyspnea

Dx: tissue biopsy (linear deposition IgG), serology

Rx: plasmapheresis, cyclophosphamide, corticosteroids

Idiopathic pulmonary fibrosis

More common in smokers

Clinically: gradual onset of progressive dyspnea, nonproductive cough, devastating lung disease

Dx: CXR shows ground glass opacity or honeycombing, definitive dx with biopsy

Rx: O2, steroids, cyclophosphamide, lung transplant (poor prognosis)

Other ILD: radiation pneumonitis, cryptogenic organizing pneumonitis, pulmonary alveolar proteinosis, hypersensitivity pneumonitis, silicosis, berylliosis

Respiratory Failure

Acute respiratory failure: PaO2 < 60, PaCO2 > 50

Causes: CNS (drugs, trauma), neuromuscular (myasthenia, guillain barre, ALS), upper airway (stenosis, spasm), mechanical (kyphoscoliosis, hemothorax), lower airway (asthma, COPD, pneumonia, ARDS)

Hypoxemic: low PaO2 with any level PaCO2

Problem with lung itself: ARDS, pneumonia

V/Q mismatch and pulmonary shunting

Hypercarbic: failure of alveolar ventilation leading to retained CO2 from lung pathology like COPD, asthma or extrapulmonary like CNS disease

V/Q mismatch: hypoxemia without hypercarbia (intrinsic lung disease)

Responds to supplemental O2

Shunting: little or no ventilation to perfused areas (eg atelectasis)

Not responsive to supplemental O2

Adult Respiratory Distress Syndrome: neutrophil activation causes inflammatory destruction of lungs

Pathophys: essentially total pulmonary atelectasis causing massive shunt

Causes: sepsis, aspiration, acute pancreatitis, trauma, toxins

Clinically: dyspnea, tachypnea, tachycardia, hypoxemia not responsive to oxygen

Dx: CXR shows diffuse bilateral pulmonary infiltrates, ABG shows hypoxemia and initially respiratory alkalosis (hyperventilation) but eventually respiratory acidosis due to respiratory fatigue, PCWP is low

Rx: O2, mechanical ventilation with PEEP, treat underlying cause

Disease of Pulmonary Vasculature

Primary Pulmonary HTN:

pulm HTN in absence of heart and lung disease

Idiopathic, usually in middle aged women

Clinically: DOA, fatigue, exertional chest pain and syncope; prominent P2

Dx: Cardiac cath to establish dx, PFTs show restrictive disease

Rx: pulmonary vasodilators (prostocyclins, CCB), warfarin due to venous stasis

Cor Pulmonale: RVF due to pulm HTN from lung etiology (no LHF)

Causes: most common is COPD, others are PE, ILD, asthma, CF, OSA

Clinically: cyanosis, clubbing, JVD, hepatomegaly, dependant edema

Dx: CXR, EKG, echo

Rx: treat underlying disorder, diuretics for volume overload, and O2

Pulmonary Embolus

From DVT of legs, pelvis, arms

Clinically: dyspnea, pleuritic chest pain, cough, hemoptysis, tachycardia, tachypnea, shock if PE is massive

Dx: ABG is NOT diagnostic (but will show low PO2, PCO2, and high pH), Helical CT is test of choice, V/Q scan (increased dead space) with contraindication to CT, angiography is gold standard but rarely used.

Rx: O2, Heparin on day 1, IVC filter if contraindication to anticoagulation

Pneumonia

Typical Pneumonia

Clinically: acute onset fevers, chills, productive cough, dyspnea, pleuritic chest pain, dullness to percussion, increased tactile fremitus

Dx: CXR shows consolidation, sputum gram stain and cultures

Community acquired (usually S. pneumo) vs Nosocomial (GNRs and S. aureus)

Atypical Pneumonia: mycoplasma pneumoniae, chlamydia pneumoniae, Chlamydia psittaci, legionella, coxiella, viruses

Clinically: insidious onset prodromal sx, dry cough, fever, no chills, normal pulse

Dx: CXR shows diffuse reticulonodular infiltrates, no consolidation

Rx: Appropriate antimicrobials

Lung Abscess: most commonly due to aspiration of GI microorganisms

Clinically: like pneumonia sometimes with foul smelling sputum and hemoptysis

Dx: CXR reveals thick walled cavitation, CT to differentiate from empyema, throat swab occasionally done but usually non-specific

Rx: drainage, augmentin/vancomycin, clindamycin/metronidazole, fluoroquinolone/ceftriaxone

Tuberculosis

Consider in immunocompromised pts (HIV, steroids, transplant, cancer) or pts from developing countries

Primary TB: granulomas wall off inhaled organisms, asymptomatic

Secondary TB: reactivation in the immunocompromised, constitutional symptoms, dry cough to purulent cough and hemoptysis

Extrapulmonary TB: lymph nodes, pleura, GU tract, spine, meninges, adrenals, etc

Dx: CXR (upper lobe cavitations, ghon complex), Sputum (cultures, AFB stain), PPD test for exposure (>15 mm induration or if immunocompromised >5mm