Lectures 1-3 Flashcards
What is the pulmonary interstitium?
Network of tissue that extends throughout both lungs, including alveolar epithelium, basement membrane, pulmonary capillary endothelium
What does the pulmonary interstitium proved support to?
The alveoli and capillary beds for gas exchange
Can the pulmonary interstitium normally be seen on CXR or CT?
No, because it is so thin
What happens to the alveoli in idiopathic pulmonary fibrosis?
There is fibrosis between alveoli which greatly decreases gas exchange
What is restrictive lung disease?
Abnormalities along the interstitium
What is a PFT or pulmonary function test?
Non-invasive tests that measure how well the lungs are expanding and contracting and how efficient the exchange of CO2 and oxygen are between the blood and air within the lungs
What are some different types of PFTs?
Lung volumes, spirometry, spirometry before and after a bronchodilator, and diffusion capacity for carbon monoxide (DLCO)
What is the lung volume?
A measure of air in L or mL
What is the total lung capacity?
The volume of air in the lungs after maximal inspiration (includes residual volume)
What is the lungs vital capacity mean?
The maximum volume of air that can be exhaled after a maximal inspiration
What is the tidal volume?
The volume of air moved in and out during each breath
What is the residual volume?
Volume of air remaining in the lungs after a maximal expiration
“Measure of breath”
Spirometry
Spirometer
An instrument for measuring the air capacity of lungs
What is the most common type of PFT?
Spirometry
Spirometry measure the volume of air exhaled (after max inhalation) at specific time points during a forceful and complete _____
Exhalation
What are the three important variables generated by spirometry?
FVC, FEV1, and their ratio: FEV1/FVC
The value found from spirometry are graded against what?
A predicted value
What are the predicted values from spirometry pooled from?
Data on a large number of “normal” individuals: no hx of lung disease, no respiratory symptoms, normal CXR, normal EKG
What can help diagnose and differentiate between obstructive lung disease and restrictive lung disease?
Spirometry
Spirometry is an important tool is assessing what?
Asthma, COPD, cystic fibrosis, pulmonary fibrosis
FVC is what?
Maximum amount of air exhaled after a maximal inhalation
What if the FVC is low?
THe problem may be a restrictive disorder
FEV1 is what?
The amount of air exhaled in the 1st second
What may a reduced FEV1 indicate?
Obstructed or narrowed airways
Most people are able to expel __% of their vital capacity in one second
70%
The FEV1/FVC ratio is used to identify what?
Airflow obstruction (if <70% of predicted)
What can flow volume loops be used for?
Strider or unexplained dyspnea
What does a flow volume loop consist of?
Forced inspiratory and expiratory maneuver
If the FEV1/FVC ratio is less than 70%, what can that indicate?
Obstructive pattern
What diseases are considered obstructive?
COPD, asthma
If the FEV1/FVC ratio is >70%, what does that mean?
Could be normal or restrictive disease
FEV1 over 70% predicted is (ATS criteria)
Mild obstruction
FEV1 60-70%
Moderate obstruction
FEV1 50-60%
Moderately severe obstruction
FEV1 35-50%
Severe obstruction
FEV1 <35% predicted
Very severe obstruction
If the DLCO is decreased, what type of obstructive disease can that signify?
Emphysema
If the DLCO is normal, which obstructive disease can it be?
Chronic bronchitis
If the DLCO is normal or increased, what type of obstructive disease can it be?
Asthma
If the DLCO is decreased, what type of restrictive disease can it be?
Parenchyma disease
If the DLCO if normal, what type of restrictive disease can it be?
Non-parenchymal (chest wall) restriction
the FEV1/FVS ratio will be decreased in which type of lung disease?
Obstructive lung disease
THe FVC will be decreased in what type of lung disease?
Restrictive lung disease
The DLCO measure what?
The overall function of the alveolar-capillary membrane
DLCO can be used to differentiate the etiology of what?
Restrictive lung disease
If the DLCO is low it could be due to what?
Interstitial lung disease
If the DLCO is normal, can be due to what?
Extrathoracic cause of restriction-obesity, chest wall disorder, neuromuscular disorder
Restrictive disease will show what results from a PFT?
FEV1/FVC ratio: normal
TLC: low
DLCO: Low
Obstructive disease will show what results from a PFT?
FEV1/FVC ratio: Low
FEV1: 46%
Pre vs Post BD: 12% increase
DCLO: Low
The inability to completely fill lungs with air
Restrictive pulmonary disease
What is restrictive pulmonary disease characterized by?
Reduced lung volumes
Unlike obstructive lung disease, restricted disease are associated with what?
A decreased total lung capacity
What are the two divisions of restrictive pulmonary disease?
Intrinsic and extrinsic
What are intrinsic restrictive pulmonary diseases?
Disease of the lung parenchyma, inflammation or scarring of lung tissue
What are some examples of intrinsic restrictive pulmonary disease?
Idiopathic fibrotic disease, pneumoconioses, and sarcoidosis
What are extrinsic restrictive pulmonary diseases?
Extra-pulmonary disease involving the chest wall, pleura, and respiratory muscles
What are some examples of extrinsic restrictive pulmonary disease?
Obesity, myasthenia gravis , ALS, kyphoscoliosis
What medications can induce interstitial lung disease?
Amiodarone, Methotrexate, and Nitrofurantoin
What is the most common diagnosis amount patients with interstitial lung disease?
Idiopathic fibrosing interstitial pneumonia
What is the overall prognosis for idiopathic fibrosing interstitial pneumonia?
Poor
Potential risk factors for idiopathic fibrosis interstitial pneumonia
Smoking, occupational exposure (stone, metal, wood, organic dusts), GERD (due to micro-aspiration)
Clinical features of idiopathic fibrosing interesting pneumonia
Insidious dry cough, extensional dyspnea, fatigue, tachypnea
What can be found on physical exam for idiopathic fibrosing interstitial pneumonia
Clubbing and inspiratory rales (crackles)
What other pulmonary disease is clubbing common in?
Cystic fibrosis, AV fistula, idiopathic pulmonary fibrosis, asbestosis, and malignancies of the lung and pleura
What GI diseases can clubbing be seen in?
Chron’s, cirrhosis, ulcerative colitis, and esophageal cancer
What will the PFTs show for idiopathic fibrosing interstitial pneumonia
Reduced FVC
Normal or elevated FEV1/FVC ratio
Reduced DLCO
Impaired 6 min walk
Radiographic findings for idiopathic fibrosing interistitial pneumonia
CXR: increased reticular markings (IPF, CHF)
CT: diffuse patchy fibrosis with pleural based honeycombing
The diagnosis for idiopathic fibrosing interstitial penumonia can be made based on what?
Basis of a characteristic presentation (symptomatology in combo with CT imaging)
What is a more definitive way to diagnose idiopathic fibrosing interstitial pneumonia?
Lung biopsy, can help rule out other possible causes as well
What types of supportive care can be given to someone with idiopathic fibrosing interstitial pneumonia?
Supplemental home oxygen, vaccinations (flu and pneumo), OP pulmonary rehab programs
What are some medication options for patients with idiopathic fibrosing interstitial pneumonia?
Nintedanib: a tyrosine kinase inhibitor
Pirfenidone (Esbriet): an anti-fibrotic drug
What are some surgical options for pts with idiopathic fibrosing interstitial pneumonia?
Lung transplant
What are the qualifications for a lung transplant?
Age <65
Free of substance abuse (smoking, drugs)
Acceptable BMI range of 20-29
“Occupational lung disease”
Pneumoconioses
What is pneumoconioses?
Groups of interstitial lung diseases caused by the inhalation and deposition of inorganic particles and mineral dust with subsequent reaction of the lung
Clinically important pneumoconiosis include:
- Coal worker’s pneumoconiosis
- Silicosis
- Asbestosis
“Black lung disease”
Coal workers pneumoconioses
What is the milder form of coal workers pneumoconioses?
Anthracosis
What is coal workers pneumoconioses caused by?
Prolonged exposure to coal dust, which is inert and cannot be removed by the body
Leads to inflammation, fibrosis, and sometimes necrosis
Coal worker’s pneumoconisoes
What are some symptoms for coal workers pneumoconioses?
Chronic cough, fever, and dyspnea on exertion usually develop 10-15 years after exposure
Radiographic findings for coal worker’s pneumoconioses
Small, rounded, modular opacities with a preference for the upper lobes
The nodular opacities in coal workers pneumoconioses tend to go where?
Upper lobes
What is coal workers pneumoconioses irreversible
When larger opacities with progressive massive fibrosis start to occur
What is silica?
Silicon dioxide (SiO2)
Silica is commonly found in nature as what?
Quartz
What are some uses for silica?
Glass, optical fibers porcelain, sand casting
Silicosis
Spectrum of pulmonary disease caused by inhalation of crystalline silica
What occupations are commonly effected by silicosis?
Mining, masonry, glass manufacturing, foundry work, and sandblasting
What are the various clinical stages of silicosis?
Acute chronic, and accelerated silicosis
What is the clinical presentation of silicosis?
Cough, dyspnea, sometimes fever or pleuritic chest pain
Evaluation of silicosis consists of what?
PFTs:
FEV1: decreased
DLCO: decreased
FEV1/FVC ratio: normal
Radiographic findings of acute silicosis
CXR/CT: bilateral, diffuse, ground glass opacities
Radiographic findings of chronic silicosis
CXR/CT: small, innumerable, rounded densities
The clinical diagnosis of silicosis is based on 3 key elements:
- History of silica exposure
- Chest imaging consisting with silicosis
- Absence of any other diagnosis
What else can be done to diagnose silicosis?
Lung biopsy if the diagnosis cannot be made clinically
What are some treatment options for silicosis?
Avoid further exposure and supportive care, steroid therapy? Lung transplant
What are some associated complications with silicosis?
Mycobacterium infection, aspergillosis, lung cancer, chronic kidney disease
Asbestos
Group of naturally occurring fibrous composed of hydrated magnesium silicates used for variety of construction and insulating purposes
Asbestosis
Pneumoconiosis caused by inhalational asbestos fibers
What occupations can be effected by asbestosis?
Plumbers, construction, shipbuilding, railways, laborers, carpenters, electricians
Clinical presentation of asbestosis
Dyspnea on exertion, cough, weight loss
How long are you asymptomatic with asbestosis?
Atleast 20-30 years after initial exposure
What can be seen on physical exam for asbestosis?
Inspiratory crackles, clubbing
What will the PFTs show for asbestosis?
Vital capacity: reduced
Total lung capacity: reduced
DLCO: low
Radiographic findings of asbestosis
CXR: thickened pleural and calcified pleural plaques
CT: course honeycombing (in advanced disease), hazy ground glass appearance of peripheral pleural surface
What is needed to diagnose asbestosis?
Hx of exposure, chest imaging consistent with asbestosis, absence of any other diagnosis, bronchoalveolar lavage
What are some treatment options for asbestosis?
Avoid further exposure, supportive care, steroid therapy, smoking cessation
What is a complication of asbestosis?
Malignant mesothelioma
Sarcoidosis
Multisystem granulomatous disorder of unknown etiology
What systems are effected with sarcoidosis?
Lungs, lymph nodes, eyes, skin, liver, spleen, heart, nervous system, but approximately 90% of pts have lung involvement