restrictive lung diseases and PH Flashcards
pulmonary function tests
- noninvasive way to measure how well lungs are expanding and contracting
- measures gas exchange
- differentiate obstructive vs. restrictive lung diseases
types of PFT
- spirometry- most common and takes into account age, gender, heigh, race
- spirometry before and after bronchodilator
- diffuse capacity for carbon monoxide (DLCO)
tidal volume
- amount of air moved in and out during each breath with normal respiration
vital capacity
- max amount of air that can be moved after max inhale and max exhale
residual volume
- volume of air remaining in lungs after max expiration
total lung capacity
- volume of air in lungs after max inspiration
- includes residual volume
FVC
- max amount of air exhaled after max inhale
- if low= restrictive disorder
FEV1
- amount of air exhaled in 1 sec
- normal > 70%
- if less than 70%= obstructive disorder
FEV1/FVC ratio
- ID airflow obstruction
- if < 70%= obstructive disorder
steps to interpreting PFTs
- FEV1- FVC ratio: less than 70%= obstructive
- rate severity of obstruction
- bronchodilator response
- TLC- < 80%= restrictive
- RV/TLC ratio- not commonly used
- DLCO
what does DLCO measure
- overall function of alveolar capillary membrane
- used to assess gas exchange
- good to differentiate eitiology of restrictive lung diseases
- low DLCO can indicate ILD
- normal DLCO can indicate extrathroacic restrictions
what is the pulmonary interstitium?
- network of tissue that extends through alveolar epithelium, basement membrane, and pulm capillary endothelium
- supports alveoli and capillary beds for gas exchange
- very thin- should not see on xray
restrictive pulmonary diseases
- inability to fill lungs with air
- reduced lung volume and total lung capacity
- can be intrinsic, extrinsic, or medication induced
medications that can cause ILD
- amiodarone
- mtx
- nitrofurantoin
intrinsic causes of restrictive lung disease
- diseases of lung parenchyma
- inflammation or scarring of lung tissue
- idiopathic fibrotic disease
- pneumoconiosis
- sarcoidosis
extrinsic causes of restrictive lung disease
- extra-pulm diseases involving chest wall
- obesity
- myasthenia gravis
- ALS
- kyphoscoliosis
idiopathic fibrosing interstitial pneumonia
- aka idiopathic pulm fibrosis (IPF)
- most common dx of pts with ILD
- poor prognosis
- mean survival- 2-5 years from time of dx
risk factors for IPF
- smoking
- occupational exposures
- GERD d/t micro-aspirations
clinical presentation if IPF
- insidious dry cough
- exertional dyspnea
- fatigue
- tachypnea
- clubbing
- inspiratory rales/ crackles
diagnosis of IPF
- PFTs- reduced FVC, reduced DLCO
- CXR- reticular markings
- CT- patchy fibrosis with pleural based honeycombing
- lung biopsy if need to r/o other causes
treatment for IPF
- supportive care
- nitedanib- tyrosine kinase inhibitor
- pirfenidone (esbriet)- antifibrotic drug
- lung transplant if < 65, no substance abuse, and BMI 20-29
supportive care for restrictive lung diseases
- home oxygen
- vaccines- flu and pneumococcal
- outpatient pulmonary rehab
pneumoconioses
- “occupational lung disease”
- ILD d/t inhalation and deposition of inorganic particles and mineral dust in lungs
- coal workers pneumoconiosis, silicosis, asbestosis
coal workers pneumoconiosis
- aka black lung disease
- d/t coal deposition in lungs that cannot be removed
what is the name for mild coal workers pneumoconiosis
- anthracosis
where is coal workers pneumoconiosis prevalent
- wyoming*
- west virginia
- pennsylvania
- illinois
- kentucky
clinical presentation of coal workers pneuoconiosis
- early- asymptomatic
- chronic cough
- fever
- DOE
- sx usually dev 10-15 years after exposure
- irreversible and progressive despite cessation of exposure
CXR findings for coal workers pneumoconiosis
- small rounded nodular opacities at first
- eventually dev larger opacities with progressive fibrosis
treatment for coal workers pneumoconiosis
- supportive care
- minimize exposure
silicosis
- d/t inhalation of crystalline silica
- silica found in glass, optical fibers, porcelain, sand casting
occupations at risk for silicosis
- mining
- masonry
- glass manufacturing
- foundry work
- sandblasting
clinical presentation of silicosis
- cough
- dyspnea
- sometimes fever or pleuritic chest pain
dx of silicosis
- decreased FEV1, decreased DLCO, normal FEV1/FVC ratio
- CXR- bilateral diffuse ground glass opacities early, small innumerable rounded densities later
- dx of exclusion
- get Tb test
treatment for silicosis
- supportive care
- avoid further exposure
- steroid therapy to minimize sequelae
- lung transplant
complications of silicosis
- Tb*
- aspergillosis
- lung cancer
- CKD
asbestosis
- pneumoconiosis d/t asbestos inhalation
- asbestos found in construction and inhalation
occupations at risk for asbestosis
- plumbers, pipefitters
- steamfitters
- biolermakers
- electricians
- insulation workers
- carpenters
- laborers
- welders
- janitors
clinical presentation of asbestosis
- usually asymptomatic for 20-30 years after exposure
- DOE
- cough
- weight loss
- clubbing
diagnosis of asbestosis
- inspiratory crackles
- reduced vital capacity, total lung capacity, and low DLCO
- CXR- thickened pleura or calcific plaques
- CCT- coarse honeycombing, hazy ground glass of peripheral pleura
- need to r/o other causes
treatment of asbestosis
- supportive care
- avoid further exposure
- steroid therapy- limited
- smoking cessation
complications of asbestosis
- malignant mesothelioma
sacroidosis
- multisystem granulomatosis disorder
- affects lungs in 90% of pts
- can also affect LN, eyes, skin, liver, spleen, heart, NS
- non-caeseating granulomas*
who is sarcoidosis common in
- young black women
- northern european whites
clinical presentation of sarcoidosis
- cough- dry and hacking
- progressive dyspnea
- atypical chest pain
- fever/ night sweats
- weighht loss
diagnosis of sarcoidosis
- CXR- bilat hilar adenopathy
- CT- right paratracheal lymphadenopathy with diffuse reticular infiltrates, galaxy sign
- dx often includes biopsy
treatment of sarcoidosis
- close observation if asymptomatic
- 90% of pts respond to PO steroids X 4-6 weeks
pulmonary hypertension (PH)
- pulmonary arterial pressure > 25 mmHg
- generally is a feature of advanced disease and need to det underlying cause
- most common cause= lung disease
causes of PH
- increased pulm vasc resistance (in pulm arteries)- most common
- elevated LA pressure
- increased pulmonary BF- limited significance
diagnosis of PH
- TTE good screening but not definitive
- gold std= R heart catheterization
TTE findings for PH
- if PH > 50 and tricuspid valve regurg velocity > 3.4 m/sec suggests PH
- if PH < 36 and tricuspid regurg < 2.8 m/sec likely NOT PH
what is the pulmonary capillary wedge pressure (PCWP)
- indirect measure of L heart pressure by inflating balloon in pulmonary artery
WHO functional classifications for PH
- I- no limit on physical activity
- II, slightly limited, comfortable at rest
- III- marked limitation, comfortable at rest
- IV- inability to do any physical activity without sx, sx at rest
cor pulmonale
- right heart disease secondary to PH
- RV hypertophy d/t pulmonary pressure -> decreased contractility
- low CO and BP -> decreased perfusion to vital organs and syncope
what is the most common cause of death in cor pulmonale
- circulatory collapse
what is the worst prognosis for cor pulmonale
- pulmonary artery hypetension
si/sx of PH
- initially asymptomatic
- DOE
- dyspnea at rest in advanced disease
- fatigue
- often goes undiagnosed or misdiagnosed
- sx of RHF
physical exam findings for PH
- initially increased intensity of S2 split
- widened S2 split
- R ventricular S3
- tricuspid regurg
- elevated JVP
- hepatomegaly
- peripheral edema/ ascites
diagnostic tests for PH
- CXR- usually normal but may see cardiomegaly
- EKG
- echo
- need to ID cause
EKG findings for PH
- R axis deviation
- poor r wave progression
- RV hypertrophy
V/Q scan
- sensitive for multiple small PE
group 1 PH
- intrinsic issue with arteries
- impacts all 3 layers of vessel wall
- dx of exclusion
possible causes of group 1 PH
- idiopathic
- hereditary
- drugs or toxins
- CT disorders
- HIV
- portal HTN
- congenital heart diseases- VSD or ASD
treatment for group 1 PH
- no effective primary tx
- requires advanced therapy
group 2 PH
- L heart disease
- LA HTN -> increased pulmonary pressure
treatment for group 2 PH
- HF treatment
- advanced therapy can be harmful
group 3 PH
- generally d/t severe lung disease and hypoxemia
- most common type
- COPD, ILD, obstructive sleep apnea
treatment for group 3 PH
- O2- only modality to improve mortality
- digoxin may improve RVEF and control HR
- advanced therapy is generally not recommended
group 4 PH
- chronic thromboemblic disease
- multiple small PE that accumulate over time
treatment for group 4 PH
- anticoagulation
- advanced therapy consideration
group 5 PH
- unclear mechanism
- may be hematologic, systemic disorders, metabolic disorders
treatment for group 5 PH
- target specific cause
- advanced therapy does have favorable response esp if d/t sarcoidosis
primary therapy for PH
- address underlying cause
advanced therapy for PH
- address PH itself
- CCB
- endothelin receptor blockers
- PDE-5 inhibitors
- lung transplant
- used in class II, III and IV despite adequate primary therapy
vasoreactive tests
- used to det if pt wil benefit from CCB
- admin short acting vasodil and measure hemodynamic response with R catheterization
- if pos admin CCB, if neg use other agents
vasoreactive agents used in testing
- enepoprostenol
- adenosine
- inhaled NO
prostanoid formulations
- improve hemodynamics, functional capacity, and survival in IPAH
- continuous infusion with implantable central venous catheter and portable pump
- only therapy to prolong survival
- epoprostenol*, treprostinil, iloprost
endothelin receptor antagonists
- improve exs capacity, dyspnea, and hemodynamics
- drugs end in “-entan”
PDE-5 inhibitors
- prolong vasodilatory effect of NO
- improves pulm hemodynamics and exs capacity
- end in “-fil”
guanylate cyclase stimulants
- stimulate NO receptor
- increase sensitivity of receptor to NO
- directly stimulates receptor to mimic action of NO
- Drug- riociguat
