Week 7: Respiratory tests, hx, ex Flashcards
What FEV1/VC ratio is considered obstructive/ restrictive
Obstructive: FEV1/VC <70%
Restrictive: FEV1/VC normal
How would an OBSTRUCTIVE lung disease affect total lung capacity and residual volume
TLC ++ (due to hyperinflation)
RV ++ (due to gas trapping)
How would a RESTRICTIVE lung disease affect total lung capacity and residual volume
TLC decreased
RV decreased/same
What are pulmonary causes of an OBSTRUCTIVE respiratory disease pattern
- COPD
- Asthma (may have normal spirometry)
- Bronchiectasis
What are pulmonary causes of a RESTRICTIVE respiratory disease pattern
Pulmonary fibrosis
What are non-pulmonary causes of a RESTRICTIVE respiratory disease pattern
- Neuromuscular disorders
- Thoracic cage abnormalities
- Obesity
Asthma is reversible with bronchodilators. What FEV1 change is considered reversed
FEV1 increased by >12% and by >200ml
What does TLCO measure
TLCO = transfer factor
Tests function of alveolar capillary membrane (V and Q)
What does KCO measure
KCO = transfer coefficient
Measures function per unit volume of lung
How are TLCO and KCO affected in asthma
Both normal
How are TLCO and KCO affected in COPD
Both reduced
How are TLCO and KCO affected in idiopathic pulmonary fibrosis
Both reduced
How are TLCO and KCO affected in extra-pulmonary causes of reduced lung function (eg thoracic cage abnormalities, obesity)
TLCO reduced
KCO increased/ normal
How are TLCO and KCO affected in pulmonary hypertension
Both reduced
Which type of CT is better for seeing a diffuse lung condition eg fibrosis
- High-res CT
- Spiral/ helical CT
High-res CT
Which type of CT is better for finding small nodules
- High-res CT
- Spiral/ helical CT
Spiral/ helical CT
5 Lung diseases that exposure to silica can cause
- Silicosis (lung fibrosis)
- Acute silicosis
- COPD
- TB
- Lung cancer
Components of light’s criteria for pleural effusion
- Protein >30g/L
- Lactate dehydrogenase >2/3
- Leukocytes
People at risk of T2 respiratory failure
- COPD
- Obesity
- Neuromuscular disorders
- Skeletal abnormalities
In which lung conditions might a broncho-alveolar lavage be useful? What are their respective findings
- Hypersensitivity pneumonitis: mast cells, lymphocytes
2. Sarcoidosis: neutrophils, lymphocytes
Contraindications for NIV
- Reduced GCS
- Facial/ upper airway trauma
- Pneumothorax + no chest drain
- Inability to protect airway (eg nerve paralysis)
Cardiogenic pulmonary oedema and chest wall deformities are NOT contraindications
How might someone with a diaphragmatic palsy present
Orthopnoea
