Prognosis: death usu. caused by medical complication (acute respiratory failure, severe pneumonia, pneumothorax, cardiac arrhythmia, pulmonary embolism) / survival with severe disease is from several up to 15 yrs
Alpha-1-antitrypsin deficiency (see liver disease)
specific type of emphysema / panacinar versus basilar
Presentation: may present as bronchiectasis
Treatment: can give a-1 AT infusions (once weekly; to maintain target level > 80 mg/dL
Cystic Fibrosis
mutations in cystic fibrosis transmembrane regulator (CFTR) / ΔF508 most common
Presentation: bronchiectasis, chronic airway inflammation, pancreatic insufficiency, male infertility (absence of vas deferens)
Childhood: H influenzae, S. aureus
Adult: Pseudomonas, Aspergillus (50% colonized; occasionally cause disease), Burkholderia (always pathogenic), atypical mycobacteria (usu. colonizers)
Diagnosis: sweat chloride test (chloride > 70 meq/L positive; 1-2% false negative) / biopsies and imaging may show chronic tissue changes but not diagnostic
Treatment: patients do much better when followed by CF specializing centers
Bronchitis
Acute bronchitis (infectious) [NEJM]
Causes:
viral URI: influenza A, parainfluenza, adenovirus, RSV, rhinovirus, human metapneumonia virus
bacterial: Mycoplasma, B. pertussis, Chlamydia, B. dermatitidis
Pathology: hyperemia then desquamation, edema, leukocytic infiltration, production of sticky or mucopurulent exudate / hypertrophy of smooth muscle and secretory epithelium / mucous plugging, resonant breath sounds, VQ mismatch from shunting, periodic exacerbations
Presentation: preceded by URI: coryza, malaise, chilliness, slight fever, back and muscle pain, and sore throat / dry cough, nonproductive or mucopurulent sputum (frankly purulent sputum suggests superimposed bacterial infection) / can have burning substernal chest pain (aggravated by coughing) / fever of 38.3 to 38.8° up to 3-5 days (cough may continue for weeks) / persistent fever suggests complicating pneumonia / dyspnea (from airway obstruction), cyanosis, cor pulmonale and edema (late), blue bloaters
Findings: scattered rhonchi, wheezing, occasional crackling or moist rales at the bases
Diagnosis:
influenza assay if indicated
sputum culture likely unrevealing or showing underlying pulmonary disease (COPD, etc.)
CXR if pneumonia suspected
multiplex PCR testing being developed (for major causative bacteria)
Treatment:
cough suppressants / B2 agonists can be considered with bronchial hyperreactivity and steroids can be considered in patients with persistent cough
ABG as needed
antibiotics when there is concomitant COPD, purulent sputum, or persistent high fever
PO macrolide or tetracycline or ampicillin 250 mg q 6 h
trimethoprim-sulfamethoxazole 160/800 mg po bid may be given
antivirals if influenza A tests positive or if testing unavailable but during epidemic or clinically suspected or children with severe RSV (no antivirals yet effective for other players 11/06)
Acute irritative bronchitis
may be caused by various mineral and vegetable dusts; fumes from strong acids, ammonia, certain volatile organic solvents, chlorine, hydrogen sulfide, sulfur dioxide, or bromine; the environmental irritants ozone and nitrogen dioxide; and tobacco or other smoke.
Chronic bronchitis
definition: chronic productive cough at least 3 months in each of 2 successive yrs for which other causes, such as infection with Mycobacterium tuberculosis, carcinoma of the lung, or chronic heart failure, have been excluded
Cough-variant asthma
in which the degree of bronchoconstriction is not sufficient to produce overt wheezing, may be caused by allergen inhalation in an atopic person or chronic exposure to an irritant in a person with relatively mild airway hyperreactivity. Management is similar to that of ordinary asthma.
Restrictive lung disease
decreased VC and TLC
poor mechanics / chronic enlarged tonsils and adenoids in young children
alveolar or interstitial fibrosis (FEV1/FVC > 90%, leads to cor pulmonale, bleomycin toxicity, gradual progressive dyspnea, cough)
Note: overbagging can stop circulation
X-ray may appear normal [pic]
ARDS – Mendelssohn’s syndrome
Diffuse Alveolar Damage
exudative stage
proliferative stage - may follow exudative - honeycomb lung - may only take 10 days
UIP - shorter course - fatal
DIP - longer course - amenable to steroid treatment - desquamation is actually histiocytes
Pneumoconiosis
acute silicosis (quartz) CWP, pulmonary tuberculosis
talcosis birefringent talc particles
CWP
dust macules
coal nodules palpable
Caplan’s syndrome fibrotic nodules
Asbestosis
ferruginous body - amphibole fiber (big) / chrysotile fiber (small) / hemosiderin accretions
associated with malignant mesothelioma of pleural surface
Obstructive Sleep Apnea (OSA)
Epidemiology: 18 million Americans / EDS in 4% of men 2% women (30-65) / 82% of men and 93% of women with moderate to severe OSA are undiagnosed / 90% of men and 98% of women with mild to severe OSA and EDS are undiagnosed
prevalence comparable to asthma
Symptoms: daytime sleepiness (accidents, problems at work, etc.) / stentorian (loud) snoring / personality changes, impotence
Mechanism: 87.5% - arousal threshold in NREM sleep / 79.5% - arousal threshold in REM sleep / other causes of REM apnea – loss of tone in tongue and pharynx, loss of coordinated intercostal function, relative bradycardia
Causes:
HTN, change in voice, nasal obstruction, micrognathia,
retrognathia, macroglossia (cleft palate), tonsillar hypertrophy, uvulopalatal enlargement/elongation, submucosal infiltration
Note: tonsillar hypertrophy is most common cause of OSA in normal children (often misdiagnosed as ADHD) / snoring may increase risk of OSA (not proven)
Obesity-hypoventilation syndrome (Pickwickian syndrome): obesity causes decreased compliance of chest wall / O2 decreased all the time (not just when sleeping) (OSA may or may not be concurrently present) / screen for hypothyroid / usefulness of progesterone debated
Allergic rhinitis: 40% present (20% incidence in general population)
Hypothyroidism: 5% present (decreased response to CO2, deposition of material increases obstruction)
Diagnosis: polysomnography > 5 episodes/hour + daytime sleepiness / hypopnea (mild/sub apnea) / 1/07 current trend is to just begin therapy with positive ambulatory nighttime pulse oximetry testing (90% likely to achieve correct diagnosis; recheck in 2 weeks for clinical improvement and then get full sleep study if uncertain)
Complications:
HTN, LVH and heart failure, dilated cardiomyopathy and CHF, MI
nocturnal cardiac disrhythmias (usu. bradycardia), sudden nocturnal death
nocturnal pulmonary HTN, early sustained pulmonary HTN and RV failure with diurnal decreased paO2 and increased paCO2 (10% incidence) / Note: rarely causes RV dysfunction without underlying COPD
association with renal disorders
Treatment:
CPAP (continuous positive airway pressure) [80% effective, eliminates mortality: treatment of choice; BIPAP is more expensive, doesn’t improve compliance, not shown to be more efficacious]
uvulopalatopharyngoplasty, tonsillectomy, other nasal and airway surgeries (40-50% effective), protriptyline 20-30 mg qhs, tracheostomy
Central Sleep Apnea (CSA)
Presentation: frequent awakenings, daytime sleepiness
Causes:
defect in respiratory muscle or metabolic control mechanism
decreased respiratory drive: sleep onset, hyperventilation (idiopathic, hypoxic, pulmonary edema of CHF, CNS), prolonged circulation time of heart failure [CNS over-corrects before chemoreceptors appreciate signals]
upper airway reflex inhibition: esophageal reflux, aspiration, upper airway collapse
Diagnosis: polysomnography
Treatment:
nocturnal supplemental oxygen
acidification with acetazolamide
CPAP (under investigation, effective in CSA secondary to CHF, may increase paCO2)
Bronchiectasis
Acquired bronchiectasis
Presentation: any age / starts early (childhood), symptomatic later / chronic cough/sputum production or sometimes asymptomatic / worsens over years / coughing boughts occur several times a day / sputum like bronchitis or more multi-layered / hemoptysis from capillary erosion (sometimes bronchial/pulmonary anastomoses) / recurrent fever or pleuritic pain (+/- pneumonia) / wheezing, SOB, etc and cor pulmonale with advanced cases (with bronchitis/emphysema)
Specifics:
severe pneumonia: Klebsiella, Staphylococci, influenza A virus, fungi, mycobacteria, mycoplasma (rarely) / pneumonia complicating measles, pertussis, or certain adenovirus
bronchial obstruction from any cause (foreign body, adenopathy, mucus inspissations, lung tumors)
chronic fibrosing lung diseases (e.g., aspiration pneumonia, injurious gases or particles (e.g., silica, talc, or bakelite)
AIDS and other immunocompromised (less common cause)
Aspergillus fumigatus has more central pattern
Associations: RA, Sjögren’s, Hashimoto’s, and UC is unexplained
Pathophysiology: may be unilateral or bilateral / lower lobes >> right middle lobe and lingula > others / reduced lung volumes and airflow rates, VQ mismatch, hypoxemia / extensive anastomoses and enlargement of bronchial/pulmonary a. and v. can cause R to L shunt PHTN cor pulmonale
Mechanism: bacterial endotoxins, proteases (bacterial/host), increased elastase, cathepsin G, and neutrophil matrix metalloproteinase (MMP-8), superoxide radicals, immune-complexes / IL-1B, IL-8, TNF-a and NO / depressed 1-antitrypsin and antichymotrypsin
direct bronchial wall destruction
infection, inhalation of noxious chemicals, immunologic, vascular abnormalities interfere with bronchial nutrition
atelectasis or loss of parenchyma with increased traction on airways, leading to bronchial dilation and secondary infection) / Note: post-obstructive decrease in mucociliary clearance (poor ciliary motility) often promotes infection (does not require complete obstruction)
Exam: persistent crackles, airflow obstruction (decreased breath sounds, prolonged expiration, or wheezing) / more pronounced in smokers / clubbing in severe, long-standing cases
Diagnosis
CXR: may show increased bronchovascular markings from peribronchial fibrosis and intrabronchial secretions, crowding from an atelectatic lung, tram lines (parallel lines outlining dilated bronchi due to peribronchial inflammation and fibrosis), areas of honeycombing, or cystic areas with or without fluid levels, but occasionally x-rays are normal
HRCT (with or without contrast): dilated airways, indicated by tram lines, by a signet ring appearance with a luminal diameter > 1.5 times that of the adjacent vessel in cross section, or by grapelike clusters in more severely affected areas. These dilated medium-sized bronchi may extend almost to the pleura because of the destruction of lung parenchyma. Thickening of the bronchial walls, obstruction of airways (evidenced by opacification--e.g., from a mucus plug--or by air trapping), and, sometimes, consolidation are other findings.
Bronchoscopy: rule out tumor, foreign body, or other localized endobronchial abnormality.
Ddx: cystic fibrosis, immune deficiencies, bronchitis, mycobacterial, fungal, Mycobacterium avium-intracellulare, Young syndrome (men, sinopulmonary symptoms and infertility), PCD syndromes, immunoglobulin deficiencies (even when total levels of IgG or IgA are normal, some IgG subclass deficiencies have been associated with sinopulmonary infections), 1-Antitrypsin (1-antiprotease inhibitor) deficiency, other congenital syndromes, yellow nail syndrome, allergic bronchopulmonary aspergillosis
Treatment:
treat active infections or underlying disorders / prophylactic or suppressive antimicrobial regimens (talk to pulmonologist)
avoid smoking and irritants
surgical resection – rarely necessary but can be considered
Congenital bronchiectasis
failure to develop proper bronchi is a rare disease / Mounier-Kuhn syndrome, Williams-Campbell syndrome
Kartagener’s syndrome
bronchiectasis, situs inversus and sinusitis / accounts for 50% of a subgroup of primary ciliary dyskinesia (PCD) syndromes (defective mucociliary clearance) / chronic rhinitis, serous otitis media, male sterility, corneal abnormalities, sinus headaches, and a poor sense of smell
Young syndrome
obstructive azoospermia, chronic sinopulmonary infections, normal spermatogenesis, a dilated epididymal head filled with spermatozoa, and amorphous material without spermatozoa in the region of the corpus / does not have ciliary defect as in PCD
Atelectasis
usually basilar, acute or chronic
Causes: O2, drug, or chemical toxicity; pulmonary edema; the adult or neonatal respiratory distress syndrome, pulmonary embolism, general anesthesia, mechanical ventilation, intraluminal bronchial obstruction, often due to plugs of tenacious bronchial exudate, endobronchial tumors, granulomas, or foreign bodies, bronchial strictures, distortion, or kinking; external bronchial compression by enlarged lymph nodes, a tumor, or an aneurysm; external pulmonary compression by pleural fluid or gas (e.g., due to pleural effusion or pneumothorax); and surfactant deficiency
Diffuse microatelectasis (seen with early ARDS)
not visible initially on CXR progresses to a patchy or diffuse reticular granular pattern, then to a pulmonary edema-like pattern, and finally to bilateral opacification in severe cases
Rounded atelectasis (folded lung syndrome)
often mistaken for a tumor / "comet tail"
complication of asbestos-induced or other pleuropulmonary disease.
Ddx: large effusion, pneumothorax
Treatment (for acute):
CPAP at 5 to 15 cm H2O
PEEP
bronchoscopy
patients with established atelectasis should lie with the affected side uppermost to promote drainage (postural drainage)
chest physical therapy – encouraged to cough –IPPB or an incentive spirometer
Aspiration
Chemical pneumonitis (aspiration pneumonitis) (Mendelson’s syndrome)
Presentation: acute dyspnea, tachypnea, tachycardia usu. 4-6 hours after aspiration of (usu.) gastric content (required sizeable aspiration)
Findings: cyanosis, bronchospasm, fever, sputum often pink and frothy
CXR: infiltrates (one or both (usu.) lower lobes)
Treatment:
Course: rapid recovery ( < 48hrs) or progression to ARDS or bacterial superinfection / mortality 30-50%
Aspiration pneumonia (see other)
Mechanical obstruction
aspiration of inert fluids or particulate matter
children: vegetal (e.g., peanuts) esp. in
adults: meat
high obstruction is obvious, but more distal can present more insidiously, clues to diagnosis:
CXR (taken during exhalation) may show atelectasis or hyperinflation of the affected lung partial obstruction with air trapping causes the cardiac shadow to shift away from the abnormal lung during this phase of respiration
recurrent parenchymal infections in the same segment of lung
Treatment: extract object, usually by bronchoscopy
Lung Abscess
Lung abscess: A localized cavity (usu. < 2 cm) with pus, resulting from necrosis of lung tissue, with surrounding pneumonitis
putrid (due to anaerobic bacteria) or nonputrid (due to anaerobes or aerobes).
Single > multiple (usu. unilateral; S. aureus becoming more common, esp. IVDA; suppurative venous thrombophlebitis due to aerobic or anaerobic bacteria)
Causes:
aspiration (alcohol, other drugs, CNS disease, general anesthesia, coma, or excessive sedation)
usually anaerobes (esp. if periodontal disease) but can be variety of organisms (Klebsiella, Staphylococcus aureus, Actinomyces israelii, B-hemolytic strep, S. milleri (and other aerobic or microaerophilic streptococci), Legionella, or H. influenzae is sometimes complicated by abscess formation)
immunocompromised (Nocardia, Cryptococcus, Aspergillus, Phycomycetes, atypical mycobacteria (primarily Mycobacterium avium-intracellulare or M. kansasii), or gram-negative bacilli, blastomycosis, histoplasmosis, coccidioidomycosis)
septic pulmonary emboli, secondary infection of pulmonary infarcts, and direct extension of amebic or bacterial abscesses from the liver through the diaphragm into the lower lobe of the lung
bronchogenic carcinoma
cavitary TB
Complications: bronchopleural fistula, ARDS
Diagnosis
CXR, CT, sputum (usu. only useful if transtracheal aspiration, transthoracic aspiration, or bronchoscopy with a protected brush)
Ddx: cavitating bronchogenic carcinoma, bronchiectasis, empyema secondary to a bronchopleural fistula, TB, coccidioidomycosis and other mycotic lung infections, infected pulmonary bulla or air cyst, pulmonary sequestration, silicotic nodule with central necrosis, subphrenic or hepatic (amebic or hydatid) abscess with perforation into bronchus, Wegener’s
Treatment
antibiotics (clindamycin or metronidazole) and/or as per suspected organisms / continue until pneumonitis has resolved and cavity has disappeared, leaving only a small stable residual lesion, a thin-walled cyst, or clear lung fields (usu. requires several weeks or months of treatment, much of which is given oral/outpatient)
postural drainage, bronchoscopy and/or surgical drainage as indicated (always drain if empyema suspected)
pulmonary resection if resistant to drugs, particularly if bronchogenic carcinoma is suspected / lobectomy versus segmental resection versus pneumonectomy (if really needed; mortality 5-10%)
Pleurisy
mechanism: underlying lung process (e.g., pneumonia, infarction, TB) / direct entry of infectious agent or irritating substance into the pleural space (e.g., with a ruptured esophagus, amebic empyema, or pancreatic pleurisy) / entry of infectious, noxious agent or neoplastic cells via the bloodstream or lymphatics / parietal pleural injury (e.g., trauma, especially rib fracture, or epidemic pleurodynia [due to coxsackievirus B]) / asbestos-related pleural disease / pleural effusion related to drug ingestion (rarely)
Presentation:
sudden pain is dominant symptom (usu. only when patient breathes deeply or coughs) / visceral pleura is insensitive (pain from inflammation of the parietal pleura innervated by intercostal nerves; usu. felt over pleuritic site but may be referred to distant regions; irritation of posterior and peripheral portions of the diaphragmatic pleura, supplied by the lower six intercostal nerves, may cause pain referred to the lower chest wall or abdomen and may simulate intra-abdominal disease; irritation of the central portion of the diaphragmatic pleura, innervated by the phrenic nerves, causes pain referred to the neck and shoulder)
respiration is usually rapid and shallow / motion of the affected side may be limited / breath sounds may be diminished
pleural friction rub, although infrequent, is characteristic sign (varies from a few intermittent sounds that may simulate crackles to a fully developed harsh grating, creaking, or leathery sound synchronous with respiration, heard on inspiration and expiration. Friction sounds due to pleuritis adjacent to the heart (pleuropericardial rub) may vary with the heartbeat as well
pleural effusion (usu. occurs along with decrease in pleuritic pain) / larger effusion with all attendant clinical implications
Diagnosis:
clinical findings and picture (may get relief by pressure on chest wall by mechanical factors) / rule out other causes (many)
CXR: cannot show pleurisy but may elucidate any underlying pulmonary infection, process
Treatment: treat underlying process (antibiotics, etc) / try to avoid impairing respiration in patient with limited pulmonary function or mental status; encourage deep breathing and cough, but balance with desire to reduce pain with pain medication and/or if appropriate, wrapping chest in elastic bandages to reduce motion / bronchodilators may help
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