Diseases Flashcards
(158 cards)
What is ACOS?
Asthma / COPD overlap syndrome
Define asthma
A chronic inflammatory disease of both large and small airways. Airway inflammation is the basic underlying process
What is the asthma triad?
- reversible airflow obstruction
- airway inflammation
- airway hyperresponsiveness
What are the hallmarks of remodelling in asthma?
- thickening of the basement membrane
- collagen deposition in the submucosa
- hypertrophy in the smooth muscle
Describe the inflammatory cascade in asthma
- inherited or acquired factors; viral, allergen or chemical
- eosinophilic inflammation
- mediators - TH2 cytokines
- twitch smooth muscle (hyper reactivity)
What would be prescribed for twitchy smooth muscle (hyper reactivity) ? (asthma)
- bronchodilators
- beta 2 agonists
- muscarinic antagonists
What would be prescribed for mediators / TH2 cytokines? (asthma)
- antileukotrienes or antihistamines
- anti IgE
- anti interleukin 5
What would be prescribed for eosinophilic inflammation? (asthma)
- anti-inflammatory medication
- corticosteroids
- cromones
- theophylline
Describe the triggers of asthma
- allergens
- others such as exercise, viral infection, smoke, cold, chemicals, drugs (NSAIDs, beta blockers0
Describe the clinical signs of asthma
- episodic symptoms and signs
- diurinal variability - nocturnal/ early morning
- non productive cough, wheeze
- triggers
- associated atopy, increased IgE (rhinitis, conjunctivitis, eczema)
- blood eosinophilia >4%
- responsive to steroid or beta-agonists
- family history of asthma
- wheezing due to turbulent airflow
Describe the diagnosis of asthma
- history and examination
- diruninal variation of peak flow rate
- reduced forced expiratory ratio (FEV.FVC <75%)
- reversibility to inhaled salbutamol
- provocation testing = bronchospasm
Describe COPD
- a multi-component disease process
- mucociliary dysfunction
- inflammation
- tissue damage
- leads to obstruction of airflow
Describe chronic bronchitis
- chronic neutrophilic inflammation
- mucus hypersecretion
- mucociliary dysfunction
- altered lung microbiome
- smooth muscle spasm hypertrophy
- partially reversible
Describe emphysema
- alveolar destruction
- impaired gas exchange
- loss of bronchial support
- irreversible
Describe the COPD clinical syndrome
- chronic symptoms, not episodic
- smoking
- non atopic
- daily productive cough
- progressive breathlessness
- frequent infective exacerbations
- chronic bronchitis, wheezing
- emphysema, reduced breath sounds
Describe the chronic cascade in COPD
- progressive fixed airflow obstruction
- impaired alveolar gas exchange
- respiratory failure ; decrease PaO2 and increased PaCO2
- pulmonary hypertension
- right ventricular hypertrophy / failure
- death
- stopping smoking arrests further decline in lung volume
Describe ACOS
- COPD with blood eosinophilia >4%
- responds better to ICS with exacerbation reductions
- more reversible to salbutamol
- difficult from asthmatic smokers who have airway remodelling (reduced FVC)
The physiology of hypoventilation leads to what?
Hypoxaemia and then to hypercarbia
What guidelines are used in the treatment of asthma?
Sign guidelines
Describe the challenge test
- use mannitol or histamine
- airways will narrow to a certain extent
Describe the benefit of flu vaccines
- reduce flu rates
- reduce admissions
- reduce severity of flu
- opportunistic vaccination
What are the challenges in primary care of asthma
- non-attendance
- SABA overuse
- who to refer to secondary care
When would you refer for additional investigation and specialist advice for asthma?
- diagnosis unclear
- suspected occupational asthma (symptoms that improve when patient is not at-work, adult onset asthma and workers in high risk occupations)
- poor response to asthma treatment
- severe / life threatening asthma attack
Describe the ‘red flags’ and indicators of other diagnoses in reference to asthma
- prominent systemic features (myalgia, fever, weight loss)
- unexpected clinical findings (eg. crackles, clubbing, cyanosis, cardiac disease, monophonic wheeze or stridor)
- present non-variable breathlessness
- chronic sputum production
- unexplained restrictive spirometry
- chest x-ray shadowing
- marked blood eosinophilia