Respiratory: Obstructive Airway disease Flashcards
What are key histological markers of airway remodelling in asthma?
Thickened basement membrane
Collagen deposition in the submucosa
Smooth muscle hypertrophy
Which drugs in asthma act to reduce the eosonophillic inflammation?
Corticosteroids
Cromones
Theophylline
Which drugs in asthma target the hyperactivity of the airways?
Bronchodilators (Beta agonist and muscarinin antagonist)
Which drugs in asthma target inflammatory mediators and Th2 cytokines?
Antileukotrienes
Monoclonal antibodies
Anti IgE
Anti interleukin5
What antibody is raised with atopic disease?
IgE
What are the two components of COPD?
Chronic bronchitis and emphysema
What is chronic bronchitis?
Inflammation of the bronchi (large and medium sized airways)
- Chronic neutrophil inflammation
- Mucus hypersectretion
- Mucociliary dysfunction
- Smooth muscle spasm and hypertrophy
What is emphysema?
Alveolar destruction resulting in impaired gas exchange and loss of bronchial support.
What vaccinations are people with COPD given?
Influenza yearly
Pneumococcal
What are the treatment stages in asthma?
SABA
SABA + ICS
SABA + ICS + LABA
SABA + ICS + LABA + Montelukast
Why might inhaled steroids (esp fluticasone) cause pnemonia in COPD?
Local immune supression and impared mucociliary clearance. Fluticasone has a prolonged period of lunge retention
When are inhlaed corticosteroids used in obstructive lung disease?
As monotherapy in asthma
With a LABA in COPD.
How is montelukast given?
Oral tablet, once daily
What is omalizumab and when is it used in obstructive lung disease?
Anti IgE monoclonal antibody.
Inhibits the binding to the high affinity IgE receptors. This inhibits the TH2 response and associated mediator release from basophils and mast cells. It is given as an injection eveery 2 - 4 weeks for patients with severe persistent allergic asthma
What is aminophylline?
IV methylxanthine used in acute attacks. Acts as a phosphodiesterase inhibitor
What is theophylline?
Oral methylxanthine used for maintainence therapy in COPD and asthma.
What is roflumilast?
A PDE4 inhibitor used in OPD where there are frequent exacarbations. It is rarely used due to severe GI side effects.
What is carbocisteine?
A mucolytic used in COPD to reduce sputum viscosity.
What is the treatment for acute COPD?
Nebulised salbutamol + Ipratropium Oral prednisolone 24 - 28 % Oxygen (titrated with SATs) Antibiotics (amoxicillin/doxycyline) IV theophyllines if there is a poor response to neubulised bronchodilators
What investigations are required if you have an infective axacerbation of COPD?
- ABG
- CXR
- ECG
- Theophylline level if on theophylline
- Sputum culture
- Blood cultures
What patients with COPD should be assessed for long term oxygen therapy? What does the assessment comprise?
FEV1 less than 30% predicted Cyanosis Polycythaemia Peripheral oedema Raised JVP Oxygen sats less than 92%
Assessment is measurement of ABG on 2 ocassions at least 3 weeks apart. Offer oxugen therapy to those with a p02 of less than 7.3 or less than 8 with
- Polycythemia
- Nocturnal hypoxia
- Peripheral oedema
- Pulmonary hypertension
What is the most common causitive organism for an infective exacarbation of COPD?
Haemophilus influenzae
Strep pneumonia
Moraxells catarrhalis
Where is the gene for alpha 1 anti trypsin found?
Chromosome 14
How is alpha 1 anti trypsin inherited?
Autosomal recessive/Co domiannt
What is the management for alpha 1 anti trypsin deficiency?
Supportive - bronchodilators
IV alpha 1 anti trypsin deficiency
Surgery - volume reduction or lung transplant
