RT Flashcards
What are the causes of type 1 respiratory failure?
hypoxaemia thickening in alveolar barrier Diffusion abnormality or V/Q mismatch PaO2 of below 8kPa SaO2 of below 90% on air =GAS EXCHANGE PROBLEM
What are the causes of type 2 respiratory failure?
poor alveolar ventilation
diffusion abnormality
V/Q mismatch eg pulmonary embolism
=VENTILATION PROBLEM
What are the causes of type 1 respiratory failure?
increased airway resistance
reduced breathing effort
decreased area of lung available for gas exchange
=GAS EXCHANGE PROBLEM
What is the effect of asthma on the bronchioles?
Muscle contraction
Inflamed & swollen mucosa
Increased mucous secreton
What is wheeze?
Expiratory noise affecting the bronchioles
What is stridor?
Inspiratory noise affecting airways around the trachea
What is dyspnoea?
Shortness of breath, breathlessness
What are the signs of respiratory conditions?
Chest movement
Respiration rate changes (should be 12-15 breaths per minute)
Air entry: is it symmetrical? is it reduced?
Vocal resonance: solid medium in lung conducts sound better than air would do
Percussion note: resonant/dull
What are the causes of type 2 respiratory failure?
hypercapnia ventilation failure airway blocking or narrowing ventilation problems - muscles acute on chronic infections PaCO2 of greater than 6.7kPa =VENTILATION PROBLEM
What is the Tx for COPD?
Smoking cessation is advised to alleviate the damage smoking causes
Anticholingerics are given to reduce basal muscle tone
Steroids are given to reduce airway inflammation
Home oxygen therapy where required is also given.
Pulmonary rehabilitation therapy can also be given.
How is cystic fibrosis managed?
CF management is given by:
Physiotherapy to improve mucus clearance from the lungs (up to an hour daily)
Exercise to improve lung efficiency and help build up bulk
Bronchodilators to open the airways
Steroids to reduce airway inflammation
DNAse to break down mucus
Antibiotics to reduce lung infections
Pancreatic Enzyme Replacement to alleviate problems posed by pancreatitis
High Calorie Diet to allow weight gain- this has dental relevance as it increases caries risk
What is the system for Tx of asthma?
- Occasional beta agonist only
- Low dose inhaled steroid or sodium cromoglycate/nedocromil (mast cell stabiliser)
- High dose inhaled steroid (brown inhaler - beclomethasone or budesonide)
- Long acting beta agonist (salmeterol), theophylline, anti-muscarinic cells
- Oral steroid (hospitalised)
What is beclometasone?
A corticosteroid in a brown inhaler
What are the inhaler colours?
SA B2 Agonist- Blue (salbutamol)
LA B2 Agonist- Green
Anticholingerics- Grey (impatropium)
Combinations- Purple
What are the corticosteroid inhaler colours?
Beclometasone- Brown
Budesonide- Brown
Fluticosone- Orange
Momentasone- Pink
What investigations can be carried out for obstructive airway diseases?
Sputum examination - colour, microscopy, bacteria Chest X-ray Pulmonary function tests (FEV1) Bronchoscopy VQ scan
What is asthma?
Reversible airflow obstruction
What are the symptoms of asthma?
Cough Wheeze SOB Problem with breathing out - hyperinflated chest Triggers - dust, smoke, environment
What are the different respiratory drugs used?
B-adrenergic agonists Anticholinergic Corticosteroids Leukotriene inhibitors Chromones Theophyllines
What are the causes of type 2 respiratory failure?
hypercapnia ventilation failure airway blocking or narrowing ventilation problems - muscles acute or chronic infections PaCO2 > 6.7kPa chronic - renal compensation for acidosis =VENTILATION PROBLEM
What are theophyllines?
Immunostimulatory drugs
Immunomodulatory drugs
Used in severe asthma as a last resort due to adverse side effects - adenosine inhibition
What is emphysema?
Loss of alveoli for gas exchange, resulting in dilation of the others to fill space - smaller number of bigger airway sacs
How is COPD classified?
Gold’s classification
Gold 1 or 2 - mild/moderate, FEV1 50-80%
Gold 3 - severe, FEV1 30-50%, cough & sputum, SOB on exertion
Gold 4 - v severe, FEV1 30%, wheeze, cough, SOB on mild exertion, overinflated lungs
What is COPD?
Combination of bronchitis and emphysema resulting in poor ventilation
Can progress to respiratory failure
What causes COPD?
smoking
environmental lung damage - coal, asbestos, lung cancer
occupational lung disease
hereditary - emphysema
What is occupational lung disease?
small airways are still present but have become thickened & less elastic
can lead to respiratory failure
fibrosis - dust related
tumours - asbestos (mesothelioma)
