Restrictive lung disease

Chest Condition RLD

1. RESTRICTIVE LUNG DISEASERESTRICTIVE LUNG DISEASE
ssharma.comssharma.com
By Sat Sharma By Sat Sharma
Assistant ProfessorAssistant Professor
University of ManitobaUniversity of Manitoba

2. BackgroundBackground
The lung volumes are reduced either because of:The lung volumes are reduced either because of:
1.1.Alteration in lung parenchyma.Alteration in lung parenchyma.
2.2.Diseases of the pleura, chest wall or neuromuscular Diseases of the pleura, chest wall or neuromuscular
apparatus.apparatus.
Physiologically restrictive lung diseases are Physiologically restrictive lung diseases are
defined by reduced total lung capacity, vital defined by reduced total lung capacity, vital
capacity and functional residual capacity, but capacity and functional residual capacity, but
with preserved air flow.with preserved air flow.

3. Restrictive lung diseases may be divided into the Restrictive lung diseases may be divided into the
following groups:following groups:
nIntrinsic lung diseases (diseases of the lung Intrinsic lung diseases (diseases of the lung
parenchyma)parenchyma)
nExtrinsic disorders (extra-parenchymal Extrinsic disorders (extra-parenchymal
diseases)diseases)

4. Intrinsic Lung DiseasesIntrinsic Lung Diseases
These diseases cause either:These diseases cause either:
nInflammation and/or scarring of lung tissue Inflammation and/or scarring of lung tissue
(interstitial lung disease)(interstitial lung disease)
oror
nFill the air spaces with exudate and debris Fill the air spaces with exudate and debris
(pneumonitis).(pneumonitis).
nThese diseases are classified further according These diseases are classified further according
to the etiological factor.to the etiological factor.

5. Extrinsic DisordersExtrinsic Disorders
The chest wall, pleura and respiratory muscles The chest wall, pleura and respiratory muscles
are the components of respiratory pump.are the components of respiratory pump.
Disorders of these structures will cause lung Disorders of these structures will cause lung
restriction and impair ventilatory function.restriction and impair ventilatory function.
These are grouped as:These are grouped as:
nNon-muscular diseases of the chest wall.Non-muscular diseases of the chest wall.
nNeuromuscular disorders.Neuromuscular disorders.

6. PathophysiologyPathophysiology
Intrinsic lung diseases:Intrinsic lung diseases:
nDiffuse parenchymal disorders cause reduction in all Diffuse parenchymal disorders cause reduction in all
lung volumes.lung volumes.
nThis is produced by excessive elastic recoil of the This is produced by excessive elastic recoil of the
lungs.lungs.
nExpiratory flows are reduced in proportion to lung Expiratory flows are reduced in proportion to lung
volumes.volumes.
nArterial hypoxemia is caused by ventilation/perfusion Arterial hypoxemia is caused by ventilation/perfusion
mismatch.mismatch.
nImpaired diffusion of oxygen will cause exercise-Impaired diffusion of oxygen will cause exercise-
induced desaturation.induced desaturation.
nHyperventilation at rest secondary to reflex Hyperventilation at rest secondary to reflex
stimulation.stimulation.

7. Extrinsic DisordersExtrinsic Disorders
nDiseases of the pleura, thoracic cage, decrease Diseases of the pleura, thoracic cage, decrease
compliance of respiratory system.compliance of respiratory system.
nThere is reduction in lung volumes.There is reduction in lung volumes.
nSecondarily, atelectasis occurs leading to V/Q Secondarily, atelectasis occurs leading to V/Q
mismatch mismatch ÜÜ hypoxemia. hypoxemia.
nThe thoracic cage and neuromuscular The thoracic cage and neuromuscular
structures are a part of respiratory system.structures are a part of respiratory system.
nAny disease of these structures will cause Any disease of these structures will cause
restrictive disease and ventilatory dysfunction.restrictive disease and ventilatory dysfunction.

8. Diseases of the Lung Diseases of the Lung
ParenchymaParenchyma

9. Structure of the Alveolar WallStructure of the Alveolar Wall

10. EM in Pulmonary FibrosisEM in Pulmonary Fibrosis

11. InterstitiumInterstitium

12. Diffuse Interstitial Pulmonary Diffuse Interstitial Pulmonary
FibrosisFibrosis
nSynonyms: idiopathic pulmonary fibrosis, interstitial Synonyms: idiopathic pulmonary fibrosis, interstitial
pneumonia, cryptogenic fibrosing alveolitis.pneumonia, cryptogenic fibrosing alveolitis.
PathologyPathology
nThickening of interstitium.Thickening of interstitium.
nInitially, infiltration with lymphocytes and plasma cells.Initially, infiltration with lymphocytes and plasma cells.
nLater fibroblasts lay down thick collagen bundles.Later fibroblasts lay down thick collagen bundles.
nThese changes occur irregularly within the lung.These changes occur irregularly within the lung.
nEventually alveolar architecture is destroyed – Eventually alveolar architecture is destroyed –
honeycomb lunghoneycomb lung

13. EtiologyEtiology
Unknown, may be immunological reaction.Unknown, may be immunological reaction.
Clinical FeaturesClinical Features
nUncommon disease, affects adults in late Uncommon disease, affects adults in late
middle age.middle age.
nProgressive exertional dyspnea, later at rest.Progressive exertional dyspnea, later at rest.
nNon-productive cough.Non-productive cough.
nPhysical examination shows finger clubbing, Physical examination shows finger clubbing,
fine inspiratory crackles throughout both lungs.fine inspiratory crackles throughout both lungs.
nPatient may develop respiratory failure Patient may develop respiratory failure
terminally.terminally.
nThe disease progresses insidiously, median The disease progresses insidiously, median
survival 4-6 years.survival 4-6 years.

18. Pulmonary FunctionPulmonary Function
nSpirometry reveals a Spirometry reveals a
restrictive pattern. FVC is restrictive pattern. FVC is
reduced, but FEVreduced, but FEV
11/FVC /FVC
supernormal.supernormal.
nAll lung volumes – TLC, All lung volumes – TLC,
FRC, RV – are reduced.FRC, RV – are reduced.
nPressure volume curve of Pressure volume curve of
the lung is displaced the lung is displaced
downward and flattened.downward and flattened.

19. Gas ExchangeGas Exchange
nArterial PaOArterial PaO
22 and PaCO and PaCO
22 are reduced, pH are reduced, pH
normal.normal.
nOn exercise PaOOn exercise PaO
22 decreases dramatically. decreases dramatically.
nPhysiologic dead space and physiologic shunt Physiologic dead space and physiologic shunt
and VQ mismatch are increased.and VQ mismatch are increased.
nDiffuse impairment contributes to hypoxemia Diffuse impairment contributes to hypoxemia
on exercise.on exercise.
nThere is marked reduction in diffusing capacity There is marked reduction in diffusing capacity
due to thickening of blood gas barrier and VQ due to thickening of blood gas barrier and VQ
mismatch.mismatch.

20. DiagnosisDiagnosis
nDiagnosis is often suggested by history, chest Diagnosis is often suggested by history, chest
radiograph and high resolution CT scan of the radiograph and high resolution CT scan of the
lungs.lungs.
nIf old chest x-rays show classical disease, If old chest x-rays show classical disease,
absence of other disease processes on history absence of other disease processes on history
and no occupational or environmental and no occupational or environmental
exposure – clinical diagnosis can be made.exposure – clinical diagnosis can be made.
nIn other cases a surgical lung biopsy is In other cases a surgical lung biopsy is
obtained.obtained.

21. TreatmentTreatment
nEach patient is individually assessed.Each patient is individually assessed.
nPatients are treated if they have symptoms or Patients are treated if they have symptoms or
progressive dysfunction on pulmonary function tests.progressive dysfunction on pulmonary function tests.
nCorticosteroids (Prednisone 1 mg/kg) is standard Corticosteroids (Prednisone 1 mg/kg) is standard
therapy.therapy.
nPrednisone dose is lowered over 6-8 weeks and Prednisone dose is lowered over 6-8 weeks and
continued at 15 mg for 1-2 years.continued at 15 mg for 1-2 years.
nAddition of Imuran may benefit survival.Addition of Imuran may benefit survival.
nCyclophosphamide occasionally used.Cyclophosphamide occasionally used.
nAntifibrotics such as colchicine may be used.Antifibrotics such as colchicine may be used.
nAncillary therapies such as oxygen, rehabilitation, Ancillary therapies such as oxygen, rehabilitation,
psychosocial aspects are helpful.psychosocial aspects are helpful.

22. SarcoidosisSarcoidosis
nA disease characterized by the presence of A disease characterized by the presence of
granulomatous tissue.granulomatous tissue.
nThis is a systemic disease which involves eyes, This is a systemic disease which involves eyes,
brain, heart, lungs, bones and kidneys, skin, brain, heart, lungs, bones and kidneys, skin,
liver and spleen.liver and spleen.
nOn pathology a non-caseating granuloma On pathology a non-caseating granuloma
composed of histiocytes, giant cells and composed of histiocytes, giant cells and
lymphocytes.lymphocytes.
nIn advanced lung disease fibrotic changes are In advanced lung disease fibrotic changes are
seen.seen.

23. EtiologyEtiology
nUnknown, likely immunological basis.Unknown, likely immunological basis.
Clinical FeaturesClinical Features
Four stages are identified:Four stages are identified:
nStage 0: No obvious intrathoracic involvementStage 0: No obvious intrathoracic involvement
nStage 1: Bilateral hilar lymphadenopathy, often Stage 1: Bilateral hilar lymphadenopathy, often
accompanied by arthritis, uveitis and erythema accompanied by arthritis, uveitis and erythema
nodosum.nodosum.
nStage 2: Pulmonary parenchyma is also involved, Stage 2: Pulmonary parenchyma is also involved,
changes in mid and upper zones.changes in mid and upper zones.
nStage 3: Pulmonary infiltrates and fibrosis without Stage 3: Pulmonary infiltrates and fibrosis without
adenopathy.adenopathy.

24. Non-caseating granulomasNon-caseating granulomas
in Sarcoidosisin Sarcoidosis

25. Stage I Stage I
(bilateral hilar adenopathy)(bilateral hilar adenopathy)

26. Stage IIStage II
Reticular nodules and BHLReticular nodules and BHL

27. HRCT – subpleural nodulesHRCT – subpleural nodules

28. Pulmonary FunctionPulmonary Function
nNo impairment occurs in stages 0 and 1.No impairment occurs in stages 0 and 1.
nIn stages 2 and 3 restrictive changes are seen.In stages 2 and 3 restrictive changes are seen.
Treatment and PrognosisTreatment and Prognosis
n85% of these patients improve spontaneously, 85% of these patients improve spontaneously,
but 15% may develop progressive fibrosis and but 15% may develop progressive fibrosis and
respiratory failure.respiratory failure.
nTreatment is other observation, but in Treatment is other observation, but in
symptomatic patients or deteriorating PFT’s – symptomatic patients or deteriorating PFT’s –
treatment recommended.treatment recommended.
nPrednisone 0.5- 1 mg/kg initially, then tapered Prednisone 0.5- 1 mg/kg initially, then tapered
and continued for 6 months to 1 year.and continued for 6 months to 1 year.

29. Hypersensitivity PneumonitisHypersensitivity Pneumonitis
nAlso known as extrinsic allergic alveolitis.Also known as extrinsic allergic alveolitis.
nHypersensitivity reaction in the lung occurs in Hypersensitivity reaction in the lung occurs in
response to inhaled organic dust.response to inhaled organic dust.
nExample is farmer’s lung.Example is farmer’s lung.
nThe exposure may be occupational or The exposure may be occupational or
environmental.environmental.
nThe disease occurs from type III and type IV The disease occurs from type III and type IV
hypersensitivity reactions.hypersensitivity reactions.
nFarmer’s lung is due to thermophilic Farmer’s lung is due to thermophilic
actinomyces in moldy hay.actinomyces in moldy hay.
nBird fancier’s lung is caused by avian antigen.Bird fancier’s lung is caused by avian antigen.

30. PathologyPathology
nThere is infiltration of alveolar walls with There is infiltration of alveolar walls with
lymphocytes, plasma cells and histiocytes.lymphocytes, plasma cells and histiocytes.
nThere are loosely formed granulomas.There are loosely formed granulomas.
nFibrotic changes occur in advanced disease.Fibrotic changes occur in advanced disease.

32. Clinical FeaturesClinical Features
nThe disease may occur in acute or chronic forms.The disease may occur in acute or chronic forms.
Acute HPAcute HP
nDyspnea, fever, malaise and cough appear 4-6 hours Dyspnea, fever, malaise and cough appear 4-6 hours
after exposure.after exposure.
nThese symptoms continue for 24-48 hours.These symptoms continue for 24-48 hours.
nPhysical examination shows fine crackles throughout Physical examination shows fine crackles throughout
the lungs.the lungs.
nThese patients present with progressive dyspnea over These patients present with progressive dyspnea over
a period of years.a period of years.
nChest radiograph may be normal, but may show Chest radiograph may be normal, but may show
reticular nodular infiltration.reticular nodular infiltration.

33. HRCT in Acute HPHRCT in Acute HP

34. Chronic HPChronic HP
nThese patients present with progressive These patients present with progressive
dyspnea.dyspnea.
nPhysical examination shows bilateral inspiratory Physical examination shows bilateral inspiratory
crackles.crackles.
nChest x-ray shows reticular nodular infiltration Chest x-ray shows reticular nodular infiltration
and fibrosis predominantly in upper lobes.and fibrosis predominantly in upper lobes.
nPulmonary function tests – restrictive pattern. Pulmonary function tests – restrictive pattern.
nGas exchange shows hypoxemia which worsens Gas exchange shows hypoxemia which worsens
on exercise.on exercise.

35. Interstitial Disease Caused by Interstitial Disease Caused by
Drugs, Poisons and RadiationDrugs, Poisons and Radiation
nVarious drugs cause acute pulmonary reaction Various drugs cause acute pulmonary reaction
– proceeding to interstitial fibrosis.– proceeding to interstitial fibrosis.
nThese drugs are busulfan, nitrofurantoin, These drugs are busulfan, nitrofurantoin,
amiodarone, bleomycin.amiodarone, bleomycin.
nHigh oxygen concentration – interstitial High oxygen concentration – interstitial
fibrosis.fibrosis.
nRadiation exposure – acute pneumonitis – Radiation exposure – acute pneumonitis –
fibrosis.fibrosis.

36. Collagen Vascular DiseasesCollagen Vascular Diseases
nSeveral collagen vascular diseases particularly Several collagen vascular diseases particularly
systemic sclerosis and lupus and rheumatoid systemic sclerosis and lupus and rheumatoid
arthritis may lead to systemic sclerosis.arthritis may lead to systemic sclerosis.
nDyspnea is often severe.Dyspnea is often severe.
nA definite diagnosis requires surgical lung A definite diagnosis requires surgical lung
biopsy.biopsy.
nTreatment is corticosteroids plus cytotoxic Treatment is corticosteroids plus cytotoxic
therapy.therapy.

37. Pleural DiseasesPleural Diseases
nPneumothorax could be either primary or Pneumothorax could be either primary or
secondary.secondary.
nPleural effusion can be acute or chronic.Pleural effusion can be acute or chronic.
nPleural effusion is divided into exudate and Pleural effusion is divided into exudate and
transudate.transudate.
nPleural thickening – longstanding pleural Pleural thickening – longstanding pleural
effusion results in fibrotic pleura which splints effusion results in fibrotic pleura which splints
the lung and prevents its expansion.the lung and prevents its expansion.
nIf the disease is bilateral – may cause If the disease is bilateral – may cause
restrictive lung diease.restrictive lung diease.
nTreatment may be decortication.Treatment may be decortication.

38. Diseases of the Chest WallDiseases of the Chest Wall
nDeformity of thoracic cage such as kyphoscoliosis and Deformity of thoracic cage such as kyphoscoliosis and
ankylosing spondylitis.ankylosing spondylitis.
nScoliosis – lateral curvature of spine, kyphosis – Scoliosis – lateral curvature of spine, kyphosis –
posterior curvature.posterior curvature.
nCause is unknown, polio and previous tuberculosis.Cause is unknown, polio and previous tuberculosis.
nPatients develop exertional dyspnea, rapid shallow Patients develop exertional dyspnea, rapid shallow
breathing.breathing.
nHypoxemia, hypercapnia and cor-pulmonale supervene.Hypoxemia, hypercapnia and cor-pulmonale supervene.
nPulmonary function tests show RVP with normal Pulmonary function tests show RVP with normal
diffusion.diffusion.
nCause of death is respiratory failure or intracurrent Cause of death is respiratory failure or intracurrent
pulmonary infection.pulmonary infection.
nTreatment is non-invasive or invasive chronic Treatment is non-invasive or invasive chronic
ventilation.ventilation.

40. Neuromuscular DisordersNeuromuscular Disorders
nDiseases affecting muscles of respiration or their nerve Diseases affecting muscles of respiration or their nerve
supply.supply.
nPoliomyelitis, Guillain-Barre syndrome, ALS, Poliomyelitis, Guillain-Barre syndrome, ALS,
myasthenia gravis, muscular dystrophies.myasthenia gravis, muscular dystrophies.
nAll these lead to dyspnea and respiratory failure.All these lead to dyspnea and respiratory failure.
nPFT’s show reduced FVC, TLC and FEVPFT’s show reduced FVC, TLC and FEV
11..
nThe progress of disease can be monitored by FVC and The progress of disease can be monitored by FVC and
blood gases.blood gases.
nMaximal inspiratory and expiratory pressures are Maximal inspiratory and expiratory pressures are
reduced.reduced.
nTreatment is either treating the underlying cause or Treatment is either treating the underlying cause or
assisted ventilation.assisted ventilation.

41. RESTRICTIVE LUNG DISEASERESTRICTIVE LUNG DISEASE
ssharma.comssharma.com
By Sat Sharma By Sat Sharma
Assistant ProfessorAssistant Professor
University of ManitobaUniversity of Manitoba