Obstructive Lung Disease Flashcards
(24 cards)
What happens to the FVC in asthma?
It is unchanged - normal
FEV1/FVC ratio in obstructive vs restrictive lung disease.
Obstructive = <75%
Restrictive = >75% (normal)
What test can be done to differentiate asthma from COPD?
Bronchial challenge test:
Response of FEV1 to a Beta agonist; asthma sees a >15% increase whereas COPD has less than 15% increase.
Transfer factors in Restrictive and obstructive disease:
TCLO/DCLO measures the diffusion capacity of the lungs by measuring the amount of carbon monoxide diffusion that occurs in a single breath.
Restrictive disease = reduced
Ephysema = reduced
Asthma = normal.
2 classes of drugs that can precipitate asthma?
Beta blockers and NSAIDs
What type of inflammation occurs in asthma?
Eosinophillic
Important parts of history in asthma?
1) Preciptants
2) Diurnal variation
3) Atopy (hay fever eczema)
4) Disturbed sleep (woken up SOB or cough = this is marker of severity)
5) Home life: pets, smokers, any changes.
6) Occupation; any triggers?
7) Impact, exercise tolerance? Activities of daily living.
Investigations for asthma (4)?
PEAK FLOW (reduced)
Spirometers (obstructive picture (normal FVC, Decreased FEV 1)
Bronchial challenge test. >15% increase with SABA
CXR shows hyperinflation (>6 anterior ribs)
Asthma treatment protocol NICE guidelines:
1) SABA as reliever
2) ICS as maintenance
3) ICS + SABA + LTRA (oral montelukast)
4) ICS + SABA +/- LTRA + LABA
5) MART (ICS + fast acting LABA) [acts as maintenance and reliever] + low dose ICS
6) MART + moderate dose ICS
7) MART + high dose ICS and consider long acting muscarinic or theophylline.
Moderate asthma attack criteria?
Increasing symptoms
PEFR 50-75% best or predicted
No features of severe acute
Features of severe acute asthma attack?
RR >25, Pulse >110
PEFR 33-50% best or predicted.
Inability to complete sentences.
Life threatening asthma attack
O2 less than 92%, Pao2 less than8
Normal CO2 (normal co2 is worrying as shows the patient is exhausted)
Any of the following:
- exhaustion
- altered level of consciousness
- Solent chest
- poor resp effort
- cyanosis
- arrhythmia
Management of acute asthma if all else fails?
IV magnesium sulphate
Management of COPD if all else fails ?
IV aminophyline
Management of acute asthma (including doses)
ABCDE (sit upright and give high flow oxygen)
Nebulised salbutamol (5mg) + Ipratropium (500micrograms)
- Give salbutamol every 15 mins and monitor ECG/
- Give ipratropium every 4-6hours.
- Hydrocortisone 100mg IV.
Ix: FBC, U&E, ABG, PEFR, CXR
Add in magnesium sulphate if not responding.
What type of inflammation in COPD?
Neutrophillic
ECG changes in cor pulmonale?
Peaked P waves and Right ventricular hypertrophy.
The hypoxia in COPD results in pulmonary hypertension which eventually leads to cor pulmonale.
- Typical features are cyanosis. Not breathless, prominent cough with lots of swelling, peripheral oedema, wheeze on auscultation (BLUE BLOATERS)
“Honey combing on CT”
Idiopathic pulmonary fibrosis.
What does the ABG show in as acute asthma attack?
Normally it shows an uncompensated respiratory alkalosis (blowing off CO2)
What is bronchiectasis?
Dilatation of the airways due to destruction of the elastic and muscular components of the airway walls.
Presents with cough and sputum production.
What sign is seen on CT scan for bronchiectasis?
Signet ring sign
Investigations for bronchiectasis?
- Spirometry - shows an obstructive picture.
- High resolution CT is diagnostic investigation
- CXR (lateral and PA) ; used for monitoring
Management of bronchiectasis?
1) Exercise and increased nutrition (pulmonary rehab)
2) Inhalers : salbutamol
3) Nebulised saline
4) Long term oral macro lines e.g. azithromycin 3x per week (helps to prevent infections)
treatment pathway for chronic COPD:
Stop SMOKING
1) SABA or SAMA (salbutamol or ipratropium)
2) Depends on FEV1
- If FEV1 > 50% = LABA or LAMA (salmeterol or tiotropium)
- if FEV1 < 50% = LABA + ICS (fool eternal + beclomethasone) or LAMA
3) LABA + ICS + LAMA
