#20 - Restrictive lung diseases Flashcards
List the 4 categories of diseases which cause restrictive thoracic disease
- pleural (eg asbestosis, pleural effusion)
- interstitial (eg, idiopathic pulmonary fibrosis.)
- neuromuscular (eg, myasthenia gravis)
- Thoracic / extrathoracic (kyphoscoliosis, obesity, ascites)
Symptoms associated with pleural effusion
Symptoms
- dyspnea
- chest pain (if parietal pleura inflamed)
- can be asymptomatic if small
For which thoracic disorders is therapy helpful ?
- pneumothorax
- sarcoidosis (steroids)
- Wegener’s granulomatosis
For which thoracic disorders is therapy NOT helpful ?
Idiopathic pulmonary fibrosis
-asbestosis (mesothelioma)
Spirometry for restrictive disorders
normal FEV1, reduces FVC.
Also, Low total lung capacity (as measured by helium gas dilution)
innervation of the pleura
parietal surface - pain fibers
diaphragmatic surface - phrenic nerve
visceral surface - no pain fibers.
T/F:
pleural pressure is positive at the functional residual capacity.
False. It is negative.
What causes a transudate in the pleural space?
changes in hydrostatic forces .
- volume overload (renal failure)
- r. atrial hypertension (CHF)
- cirrhosis
What causes an exudate in the pleural space ?
increased leak across capillaries (active secretion of fluid!!!)
- infection (pneumonia)
- inflammation (rheumatoid arthritis)
- infiltration - cancer
NOTE: These things (3I’s) obstruct the lymphatic duct, meaning that fluid normally excreted into the pleural space cannot drain.
First step in evaluation of a pleural effusion
-determine trasudate vs. exudate
Transudate vs. Exudate in terms of
- protein
- cell count
Transudate = protein poor, low cell count
Exudate = protein rich, cellular
Physical exam signs associated with pleural effusion
- percussion dullness
- absent breath sounds
- egophony (nasally voice sound)
how do you tell if there is fluid vs. consolidation in the lung on X ray?
Meniscus = clear cut border. When meniscus is present, you know it is fluid, not consolidation.
How do you determine if there is enough fluid in the pleural space to tap.
- ultrasound
- decubitus x ray with layering effusion (fluid moves when they lay on their side)
When is aspiration of fluid from pleural cavity NOT indicated?
- rarely
- very small effusions
- CHF effusions
Should the aspiration needle hug the bottom or the top of the rib??
the top - neurovascular bundle on the bottom.
List LIGHT’s criteria - what are the criteria for
Any of these criteria define an exudate
- pleural fluid protein / serum protein >0.5
- pleural fluid LDH/ serum LDH >0.6
- pleural fluid LDH >2/3 upper limit of normal serum LDH
If none of these criteria are met, it is a transudate.
If none of Light’s criteria are met. It is a transudate. What is the next step.
No need for further invasive evaluation.
Treat underlying disease (diuretics, dialysis, for renal/heart failure, etc)
LDH=
lactate dehydrogenase. a general indicator of tissue and cellular damage.
If light’s criteria are met, what is the probable diagnosis/ next step?
probable diagnosis = infection or malignancy
Pneumothorax symptoms
sudden onset chest pain and dyspnea
Pneumothorax =
air in the pleural space
Physical exam for pneumothorax
- no breath sounds
- hyperresonance
Primary pneumothorax is due to
rupture of apical subpleural blebs (no underlying disease, but common in smokers and thin people)
Secondary pneumothorax is due to
pre-existing lung disease (COPD, CF, tuberculosis, etc)
When should you suspect tension pneumothorax and what should you do?
-suspect when you see sudden deterioration on a ventilator, after a biopsy or central line placement.
Give 100% oxygen and immediate pleural decompression, without waiting for x ray confirmation.
Pneumothorax therapy
-they can be observed if small (
Which is more common - mesothelioma or metastasis to pleura?
metastasis to pleura. - lung, breast, lymphoid most common.
Most common cause of mesothelioma. how to diagnose?
asbestos exposure. diagnose with a biopsy.
Treatment/ prognosis for mesothelioma
pallative care - deadly disease w/ little response to chemo.
T/F: Whether spontaneous or traumatic, a pneumothorax usually needs chest tube drainage
true
What happens to compliance and elasticity in interstitial restrictive diseases ??
compliance goes down, elasticity goes down.
Physical exam in interstitial restrictive diseases
- clubbing
- rales/crackles heard at bases of both lungs
4 categories of disease which cause interstitial lung disease (restrictive)
idiopathic - idiopathic pulmonary fibrosis.
- occupational exposures - silicosis, asbestosis.
- medications (chemotherapy)
- autoimmune (rheumatoid arthritis)
Reserve volume, total lung capacity, and diffusing capacity in restrictive diseases.
they are all low! Contrast w/ COPD - volumes high, diffusing capacity low
Where does occupational lung disease usually occur? Why?
upper lobe, due to inhalational properties
idiopathic pulmonary fibrosis usually targets which part of the lung?
lower lobe
x ray for interstitial lung disease
decreased lung volume
Workup of interstitial lung disease
CT is almost always done
honeycombing happens in what disease
idiopathic pulmonary fibrosis.
Granulomas in the lung suggest?
sarcoidosis or a foreign body exposure.
Usual interstitial pneumonitis (fibrosis) occurs in which conditions?
it occurs in all interstitial conditions in late stages - “final common pathway”
T/F - pulmonary fibrosis is usually unresponsive to therapy
True.
CXR for sarcoidosis
hilar adenopathy
upper lobe predominance
Treatment for sarcoid
steroids are effective treatment.
T/F : Collagen vascular disease is as lethal as idiopathic pulmonary fibrosis
False - it has generally better prognosis, more benign
symptoms for sarcoid
- often asymptomatic
- rash preceding symptoms
Calcification along the pleura
asbestosis (pathognomonic)
If you suspect interstitial lung disease, you should test for c-ANCA and PR3-ANCA, to test for which disease?
wegener’s granulomatosis.
3 primary characteristics of interstitial lung disease
- lung scarring
- reduced lung volumes
- reduced compliance of the lung.
most common treatment for interstitial lung disease
corticosteroids (may not work)
Lung disease + Birifringent bodies in a polarizing microscope
silica
talc
lung disease + bodies that look like a brown dumbell under microscopy
asbestos bodies
Presentation of neuromuscular lung disease
- paradoxical inward movement of abdomen (due to diaphragm weakness)
- shallow breathing (due to diaphragm weakness)
- recurrent infections due to reduced cough strength
treatment for neuromuscular lung disease
oxygen, assisted cough.
How is restrictive lung disease defined?
low total lung capacity.
