Restrictive thoracic disease Flashcards
What are the causes of restrictive thoracic disease outside of the lung?
Skeletal- scoliosis of the spine, rib fractures, ankylosing spondylitis
Muscle weakness- Myopathy, neuropathy, myelopathy
Abdominal obesity- compression of thoracic content
Pregnancy
What causes restrictive thoracic disease within the lung?
Diffuse Parenchymal Lung Disease DPLD
Also know as Interstitial lung disease- ILD
WHat are the 5 different types of DPLD?
1) Acute
2) Episodic
3) Chronic due to occupational or environmental exposure
4) CHhronic with evidence of systemic disease
5) Chronic with no evidence of systemic disease
What is the pathophysiology of DPLD?
Disease of the alveolar structures.
Impaired alveolar gas exchange involving the alveolar arteriolar barrier.
Is carbon dioxide exchange impaired in DPLD and why?
No because ventilation is normal and carbondioxide is very soluble in the membranes
What are the causes of DPLD? (6 things)
Fluid in the alveolar air spaces Consolidation in alveolar air spaces Inflammatory infiltration of alveolar walls Pneumoconiosis Carcinomatosis Type 1/3 hypersensitivity response
What are causes of fluid in the air spaces?
Cardiac pulmonary oedema due to left ventricular failure leading to back pressure in the left atrium, pulmonary veins and capillaries
Non cardiac pulmonary oedema. Leaky capillaries due to dysfunctional tight junctions from trauma or sepsis
What are the causes of consolidation in alveolar air spaces?
Infective pneumonia
Infarction due to PE or vasculitis
BOOP- bronchiolitis obliterons organising pneumonia
What causes alveolitis?
Extrinsic allergic alveolitis due to extrinsic antigen (type 3 hypersensitivity- IgG mediated)
Sarcoidosis- multisystem swelling of lymph nodes, inflammation of nerves and heart and erythema nodosum
Drug induced- Methatrexate, aminodarone, bleomycin
Toxic fumes- chlorine
Pulmonary fibrosis
Autoimmune- SLE
What are the 2 types of pneumoconiosis?
Fibrogenic- asbestosis, silicosis
Non fibrogenic- Iron, Tin Barium
Which adenocarcinomas are most likely to metastasise in the lung and cause carcinomatosis?
Broncho, breast, prostate, colon and stomach
What is the difference between asthma and eosinophilic DPLD?
In asthma, eosinophils infiltrate the bronchial tree whereas in eosinophilic DPLD the eosinophils infiltrate the alveolar tissue
What are the clinical signs of DPLD?
Breathless on exertion Cough but no wheeze Finger clubbing Inspiratory lung crackles Central cyanosis Pulmonary fibrosis
What would you expect to find with spirometry in DPLD?
Restrictive pattern
Decreases FEV1 and FVC
Normal FEV1:FVC ratio of >75%
Normal peak flow
What test would you do to assess gas diffusion?
DLCO
