Respiratory Flashcards
(147 cards)
What is FEV1?
Forced expiratory volume in 1 second
What is FVC?
Forced vital capacity, the total amount of air forcibly expired.
What are the values for FVC in airways restriction?
Lower than 80% with a normal FEV1:FVC ratio
What are the values for Airway obstruction?
FEV1:FVC ratio is below 0.7
What are the 2 types of COPD?
Chronic bronchitis and emphysema
What is chronic bronchitis?
Increased mucus production due to irritants.
Pathophysiology of chronic bronchitis?
Mucus narrows airways, hypertrophy and hyperplasia in the mucus glands due to increased irritants.
Not as much O2 can come in and CO2 can’t get out due to the mucus.
What do patients with chronic bronchitis present with?
Hypercapnia and hypoxemia as the mucus plugs prevent O2 from entering the lungs and CO2 from leaving.
What is emphysema?
Increased breakdown of elastin in the lungs leading to reduced recoil of the lungs.
Pathophysiology of emphysema?
Macrophages phagocytose pollutants/particles, release cytokines, attracting neutrophils to the area.
Elastase is released which breaks down elastin.
Alveoli collapse due to lack of elastin.
What is alpha-1 antitrypsin?
An inhibitor of the enzyme elastase
What does this mean for patients with alpha-1 antitrypsin deficiency?
There is more elastase and therefore leads to the development of emphysema.
What are the risk factors for COPD?
Smoking, exposure to particles and pollutants.
Which patients are described as blue bloaters?
Patients with chronic bronchitis, commonly have a high BMI and cyanosis due to hypercapnia.
Which patients are described as the pink puffers?
Chronic emphysema, exhale through pursed lips to prevent alveolar collapse.
Presentations of chronic bronchitis?
Chronic productive cough, sputum, wheezing on expiration, inspiratory crackles, dyspnoea on exertion, hyper resonance to percussion.
Presentations of emphysema?
Weight loss, wheezing on expiration, hyper-resonance to percussion.
What are the gold standard tests for COPD?
Pulmonary function tests and spirometry. Do tests with and without bronchodilators if theres less than a 12% increase in FEV1 its likely to be COPD.
When should you start COPD on supplemental O2?
if O2 is less than 88%, if they have other conditions then start at 90%
What will you see on ABG in COPD?
Elevated CO2 low pH and low O2
What might a CXR show in COPD?
Can show a flat diaphragm, hyperinflation, air trapping and bullae (an air pocket due to emphysema)
Differential diagnoses for COPD?
Asthma, congestive heart failure, bronchiectasis.
Management of COPD generally?
Smoking cessation, influenza and pneumococcal vaccine.
Mild or intermittent COPD?
SAMA or SABA with a spacer