Obstructive Airway Disease Flashcards
List the symptoms of respiratory disease.
Cough: dry or sputum producing. (Can sometimes contain blood)
Wheeze - expiratory noise
Stridor - inspiratory noise
Dyspnoea - distress when breathing
Pain - general or on inspiration
List the sign of reparatory disease.
Respiratory rate: > 12-15 ppm.
Chest movement: Should have bilateral expansion
Percussion
Vocal resonance:
Ask patient to speak whilst listening to their chest.
If voice is clear = abnormality
If voice is muffled = healthy
List some respiratory investigations.
Sputum examination.
Radiographs
FEV1
FEV1/VC
Peak expiratory flow rate
What test is used to diagnose and monitor asthma?
Describe how this is carried out.
peak flow test/PEFR (peak expiratory flow rate):
Breathe in as much as you can and force out as much air as you can in 1 second.
3 readings are recorded and an average is taken.
This is carried out before treatment and after treatment using b2 agonists.
List the possible respiratory diseases.
Infection e.g. pneumonia
Tumour
Airflow obstruction e.g. COPD - asthma, emphysema. Restrictive pulmonary change.
Gas exchange failure e.g. fibrosis (scar tissue) , fluid in the lungs.
Is asthma reversible?
yes - reversible obstructive airway disease
What causes asthma?
Hyper reactivity to minor stimuli
Describe the mechanisms of asthma.
Contraction of smooth muscle
Excessive mucous secretion
Mucosal oedema from inflammation
What causes the wheeze in asthma?
The narrowing of airways
What causes the cough in asthma?
The excess mucous secretion
What will the patient complain of when presenting asthma?
Cough, wheeze and shortness of breath.
What is a strong indictor of asthma?
Diurnal variation - worse at night (and in the morning)
List the triggers for asthma.
Infection Dust Smoke Cold air (common in children) atopy - heightened immune response
What is asthma usually associated with?
other autoimmune disease i.e. eczema
What are the signs of an asthma attack?
wheezing
Increased respiratory rate
Increased heart rate
Severe attack:
Inability to talk
Confusion
Describe the responses in an asthma attack.
Biphasic
Early response and a late response
How would you determine severe asthma?
If oral steroids have been taken more than once a year.
Colour of inhaler (i.e pink/orange inhalers)
If the patient has had to be admitted to hospital more than once per year.
If they attend a specialist
What is the most useful medication used to treat asthma?
Steroids
What is COPD?
A combination of reversible obstruction and destructive lung disease.
Give an example of COPD.
Asthma, emphysema and chronic bronchitis
What is emphysema?
Where some alveoli are destroyed therefore other alveoli enlarge and become inflamed to compensate.
How do you classify severity of COPD?
Using Gold Classification
Describe the Gold classification of COPD.
1/2 = mild : cough and little/no breathlessness
3 = severe : Cough with sputum and breathlessness on exertion.
4 = very severe : cough and wheeze, breathlessness on mild exertion, lung over inflation, cyanosis and peripheral oedema.
What causes COPD?
Smoking
Hereditary
Environmental factors e.g. smoke, chemicals, occupational exposure.
OE:
Dust = fibrosis
Asbestos = tumours
How is COPD managed?
Anticholinergic drugs e.g. ipratropium Oxygen support Smoking cessation Inhaled steroids e.g. beclamethasone Long acting bronchodilators e.g. salmeterol
What does treatment success reflect?
Reversibility of the disease.
What can COPD progress to?
Respiratory failure
Describe type 1 respiratory failure.
Alveolar diffusion fails : thickening of the alveoli means that diffusion of oxygen cannot occur.
= hypoxia
< 8pKa partial pressure of arterial oxygen
Describe type 2 respiratory failure.
Ventilation fails : can’t breathe out CO2
= Hypercapnia
> 6.7 pKa partial pressure CO2 in arterial blood.
What are the causes of type 2 reparatory failure?
Airway blockage/narrowing
Problems with muscles - cant ventilate
What occurs in chronic respiratory failure?
Renal compensation for acidosis.
What controls normal breathing?
CO2 controls ventilation
What controls breathing in COPD?
Hypoxia controls ventilation
Why must you be cautious when giving a patient with COPD high concentrations of oxygen?
COPD patients rely on hypoxia to control breathing.
If you force oxygen into the system it removes their drive to breath on their own.
Results in type 2 reparatory failure (failure of ventilation)
Type 2 failure = Acidosis of the lungs
