Lecture 6: Respiratory diesase(s) and pulmonary function assessment Flashcards
Describe the clinical characteristics of Asthma?
Airway hyper-responsiveness to trigger factors (bronchoconstriction)
Reversible airway narrowing - use of inhaler can negate affects
Obstructed flow rate
Present with variable symptoms - breathlessness (dyspnoea), wheezing, tightness of chest.
Describe the clinical characteristics of COPD?
Inflammation of the airway
Permanently obstructed airflow - less reversible to any inhaler medication
Deterioration of lung function - gaseous exchange impaired due to damage to the alveolar sacs.
Present with persistent symptoms: wheeze, cough, shortness of breath, tightness in chest.
How would you differentiate between Asthma and COPD?
Asthma has an early onset with intermittent symptoms as opposed to COPD where the onset is later and the symptoms are persistent. Asthma has a good response to inhaled medication/ therapy whereas COPD’s affects are less reversible
COPD is associated with long term smoking but Asthma is atopic.
What are the factors of an obstructive patients flow volume loop?
FEV1 <80% of predicted/normal
FVC can be normal or reduced, If reduced the magnitude of reduction is less than FEV1.
FEV1/FVC ratio below 70%
What are the factors of a restrictive patients flow volume loop?
FEV1 normal or mildly reduced (not significant)
FVC below 80% of predicted/normal ranges
FEV1/FVC ratio normal OR above 70% >70%.
What are the factors of a normal patients flow volume loop?
FEV1 and FVC above 80% predicted/normal ranges
FEV1/FVC ration must be above 70% - the patient can exhale 70% of FVC in one single breath.
Define Spirometry and discuss its use in clinical practice?
Spirometry is a method of assessing lung function. The spirometry test produces a number of variables which allows for the differentiation of obstructive disease (COPD, asthma) or restrictive disease (pulmonary fibrosis).
