Respi Flashcards
Why is there pulmonary hypertension secondary to COPD?
The structural basis of PH in COPD:
- Remodelling
- Reduction in pulmonary vessels
- Pulmonary thrombis
Pulmonary vascular remodelling pathology
1. Muscularisation of pulmonary arterioles. This part of the pre-capillary vascular bed, <80 μm in diameter, is without muscular layer in normal subjects. In transverse section, pulmonary arterioles in severe COPD patients have distinct media of circularly oriented smooth muscle bounded on its outer and inner aspects by elastic laminae. This is due to hypertrophy, proliferation and transformation pericytes (contractile cells) which are precursors of smooth muscle cell, or transformation of intermediate cells. Muscularisation also occurs in the post-capillary vessels of patients with COPD 35 with a more important amount of extracellular matrix in veins and venules than in pulmonary arteries.
- Changes in intima
Pathophysiology
1. Inhaled noxious particles and gases in smokers lead to an inflammatory process with an increased number of CD8+ T-lymphocytes in the wall of central and peripheral airways of smokers and patients with COPD. Interestingly, the same infiltrate of inflammatory cells is present in pulmonary vascular lesions.
Pulmonary vascular remodelling in COPD is the main cause of increase in pulmonary artery pressure and is thought to result from the combined effects of hypoxia, inflammation and loss of capillaries in severe emphysema.
What worsens pulmonary hypertension?
Exercise, sleep and exacerbation
Give examples of URTI and LRTIs.
URTI
Otitis
Severe sore throat
Rhinopharyngitis
LRTI
Pneumonia
Bronchopneumonia
Bronchitis
Why would there be dull or resonant sounds upon auscultation?
Dullness
Fluid
Consolidation
Fibrosis
Scars
*Resonance* Decreased density (pneumothorax) => decreased breath sounds, decreased whispering pectoriloquy
Why would there be increased or decreased
whispering pectoriloquy?
Increased whispering pectoriloquy
Fluid mass (consolidation etc)
Solid mass
Decreased whispering pectoriloquy
Decreased density due to pneumothorax
What causes increased or decreased breath sounds?
Increased breath sounds
Due to the presence of more ‘material’
Usually presents with bronchial sounds
Decreased breath sounds
Lung collapse
Causes of fine and coarse inspiratory crackles?
Fine inspiratory crackles
Pulmonary fibrosis
Interstitial tissue
Coarse inspiratory crackles
What would you expect upon examination of a patient with COPD and interstitial lung disease?
Tachypnia
Obstruction upon expiration =>??
What is the difference between a monophonic wheeze and a polyphonic wheeze?
Monophonic wheeze
One obstruction in one airway
The more central it is, the louder it will be
Usually presents with stridol
Polyphonic wheeze
At least two obstructions in multiple airways
What is stridor?
High pitched wheezing sound caused by disrupted airflow
Why are bronchial sounds heard?
Bronchial sounds are generated by turbulent air flow in large airways, such as the trachea in healthy patients. In healthy patients, these sounds are not conducted to the chest wall since they are attenuated by air filled alveoli and lung parenchyma.
Consolidation or fibrosis => sound of air flow in the bronchi is conducted more effectively to the chest wall and bronchial rather than vesicular breath sounds are heard.
What is the vocal fremitus in patients with consolidation and pleural effusion. And why?
Consolidation
Increased tissue density due to consolidation => Increased transmission of low frequency sounds => Increased vocal fremitus
Pleural effusion
Fluid collects between the visceral and parietal pleura => Lung parenchyma pushed away from chest wall => Decreased vocal fremitus
https://knowledge.statpearls.com/chapter/0/31243?utm_source=pubmed
Spirometry is an essential part of the diagnosis of COPD. In addition to recording spirometry (a volume/time curve), flow volume curves may also be performed. The shape of these sometimes helps differentiate asthma from COPD. If a flow volume curve shows a sharp but reduced peak of expiratory flow, after which, the flow proceeds at a very low rate twoards residual volume, it indicates COPD. True or false?
True. If a flow volume curve shows a sharp but reduced peak of expiratory flow, after which the flow proceeds at a very low rate towards residual volume, it indicates COPD.
