Respiratory Flashcards
What is A1AT?
Features?
Pathophysiology and inheritance?
Alpha-1 antitrypsin deficiency - AR or co-dominant inhertiance.
Lack of protease inhibitor normally produced by the liver -> panacinar emphysema, esp in lower lobes.
Cirrhosis and hepatocelluar ca in adults, cholestasis in children.
Often misdiagnosed as asthma or COPD.
What would you expect on a blood gas of someone in DKA?
Metabolic acidosis, with increased anion gap (due to ketones)
At what pO2 would you offer someone with COPD long-term O2 therapy?
pO2 <7.3 kPa OR 7.3-8kPa with: - secondary polycythaemia - nocturnal hypoxaemia - peripheral oedema - pulmonary HTN
Varenicline or buproprion are prescribed as nicotine replacement therapy - how do they work?
Varenicline: nicotinic receptor partial agonist
Bupropion: NA and dopamine reuptake inhibitor, nicotinic antagonist
What is the most common sign seen on CXR when a patient has been exposed to asbestos in the past?
Pleural plaques - these are BENIGN and do not undergo malignant change. Generally occur after latent period 20-40 years
What is the most common form of cancer following asbestos exposure?
Bronchial carcinoma (more common than mesothelioma but has other causes)
What are the next steps in management for a patient with COPD that is still breathless despite first-line (SABA or SAMA) use?
How does this differ by FEV1?
FEV1 >50:
- LABA
or
- LAMA
FEV1 <50:
- LABA + ICS combo
or
- LAMA
What is the mx of cor pulmonale?
Loop diuretic for oedema
Consider LT O2.
What if a COPD patient is still breathless despite 2nd line therapy?
What if even this is ineffective? What if people can’t tolerate inhaled therapy?
If taking LABA then switch to LABA + ICS combo
If taking LAMA then add LABA + ICS combo
4: Trial theophylline (reduce dose if macrolide or fluoroquinolone abx co-prescribed)
What would the combination of ENT, respiratory and kidney involvement in a patient suggest?
Granulomatosis with polyangiitis (GPA) - formerly Wegener’s.
What are the features of Granulomatosis with polyangiitis?
(= autoimmune necrotising granulomatous vasculitis)
- URT: Epistaxis, sinusitis, nasal crusting
- LRT: Dyspnoea, haemoptysis
- Rapidly progressive glomerulonephritis
- Saddle-shape nose deformity
- Vasculitic rash, eye involvment, CN lesions
What do cANCA classically relate to?
(cytoplasmic antineutrophil cytoplasmic antibodies)
Granulomatosis with polyangiitis
What do pANCA classically relate to?
(perinuclear antineutrophil cytoplasmic antibodies)
Churg-Strauss
(25% Gran with poly are cANA positive)
What would epithelial crescents in Bowman’s capsule on renal biopsy suggest?
Granulomatosis with polyangiitis
What is the mx of granulomatosis with polyangitis?
-Steroid
- Cyclophosphamide (90% response)
- Plasma exchange
Median survival is 8-9 years
What is the Ix of suspected asthma in adults?
All patients should:
- Spirometry with bronchodilator reversibility test (BDR)
- FeNO test (fractional exhaled nitric oxide - levels correlate with levels of inflammation)
What is the combination of erythema nodusum and bilateral hilar lymphadenopathy on CXR pathognomonic of?
What other features might they have?
Sarcoidosis
- Swinging fever
- Polyarthralgia
- Hypercalcaemia
- Raised serum ACE
- Uveitis
- Insidious: dyspnoea, non-productive cough, malaise, weight loss
What are the feature of Churg-Strauss syndrome?
- Asthma
- Eosinophilia (>10%)
- Paranasal sinusitis
- Mononeuritis multiplex
- 60% pANCA +ve
What is Samter’s triad?
Aspirin sensitive asthma:
- Nasal polyps
- Sensitivity to NSAIDs
- Asthma
What is the stepwise mx of asthma?
1: SABA
2: (or 1 if newly-diagnosed + symptoms >= 3 / week or night-time waking) SABA + low-dose ICS
3: SABA, low-dose ICS, LTRA
4: SABA, low-dose ICS LABA, continue LTRA depending on response
5: SABA +/- LTRA. Switch ICS/LABA for MART including low-dose ICS
6: SABA +/- LTRA + medium-dose ICS MART
7: SABA +/- LTRA + one of:
- High-dose ICS
- Trial LAMA or theophylline
- Refer
What are the main contradictions to surgery in non-small cell ca?
- SVC obstruction
- FEV <1.5
- Malignant pleural effusion
- Vocal cord paralysis
- Mets
- General poor health
When would you consider invasive ventilation in COPD when medical therapy is ineffective?
If pH <7.25
7.25-7.35 NIV - BiPAP
What would be the typical x-ray and hx for aspergilloma?
Haemoptysis - may be severe.
Rounded opacity on CXR.
Past hx of TB, sarcoid, bronchiectasis, CF… i.e. anything causing a cavity.
How does mitral stenosis cause haemoptysis?
What else would you find O/E?
Pulmonary congestion -> bronchial vein rupture, due to back pressure in LA
- Dyspnoea
- AF
- Malar flush on cheeks
- Mid-diastolic murmur
How would you exclude cardiogenic pulmonary oedema in suspected ARDS?
Pulmonary capillary wedge pressure <18 mmHg
What would you do if you suspected occupational asthma?
- Serial measurements of peak flow at work and away from work
- Refer to specialist
(Isocyanates are most common cause - spray painting and foam moulding)
What is the most important advice to give a patient following a primary pneumothorax in terms of preventing further?
Stop smoking (10% risk vs 0.1%)
How do you differentiate acute and chronic respiratory acidosis?
Bicarbonate - high in chronic as metabolic compensation.
What type of lung ca is most likely to cause a paraneoplastic syndrome?
Small cell.
What is the most appropriate action to ensure settling of an asthma exacerbation?
Salbutamol nebs
Pred 40mg OD for 5 days
