Respiratory Flashcards
what are the causes of a restrictive picture on FEV1/FVC?
fibrosis, obesity, sarcoidosis, pneumoconiosis, interstitial pneumonia, connective tissue disesase, massive pleural effusion, chest wall defects (kyphoscoliosis)
what is the KCO?
the gas diffusion coefficient: represents the carbon monoxide diffusing capacity corrected for alveolar volume
how is TLCO measured?
a single inspitation of CO held for 10s, then CO measured in the blood.
TLV is measured with a helium dilution test
what are the causes of a high and low KCO?
high - alveolar haemorrhage
low - emphysema and interstitial lung disease
what does this flow-volume loop represent?
there is a characteristic defect in the expiratory phase of the flow volume loop.
This is commonly seen in intra-thoracic chest disease.
examples include asthma and emphysema
what does this abnormal flow-volume loop represent?
there is a characteristic pathological pattern during the inspiratory phase of this flow volume loop.
This typically represents an extra-throacic pathology.
An example would be tracheal obstruction, whereby during inspiration negative pressure the airway obstruction is sucked into the lumen reducing the flow of inspired air
what is the role of USS in respiratory medicine?
USS is commonly used to guide pleural drain insertion and pleural aspiration, especially in the case of loculated effusion/empyema
what is broncheoalveolar lavage? indications? complications?
BAL - performed during USS guided bronchoscopy. warmed 0.9% saline instilled into the distal airway and aspirated. fuild sent for lab testing.
- *indications** -
diagnostic: ?malignancy, ?pneumonia, ?bronchiectasis, ?TB, interstitial lung disease (sarcoid, pneumoconiosis, EAA)
therapeutic: alveolar proteinosis
complications
transient shadow on CXR, transient hypoxia (give O2), transient fever
infection (rare)
what are the methods for lung biopsy? when are they useful?
- percutaneous needle biopsy* with USS guidance - peripheral tumours located on chest CT
- transbronchial, performed during bronchoscopy* - interstitial lung disease (sarcoid, IPF)
what is the indication of mediastinoscopy?
for visualisation, examination and biopsy of medisatinal lymph nodes/lesions
who should be offered pneumococcal vaccine?
how frequently is the vaccine given?
- adults >65 y/o
- chronic heart, liver or renal failure patients
- DM not controlled by diet alone
- immunosupression: splenectomy, AIDS, chemo or pred >20 mg/OD
every 5 years
what are the complications of pneumonia?
lung: respiratory failure (type I), parapneumonic effusion, empyema (pus in pleural space), lung abscess
systemic: hypotension, atrial fibrilation (elderly), sepsis, death, pericarditis/myocarditis, jaundice (co-amox and flucloxacillin)
define bronchiectasis
chronic inflammation and insult to the airways leads to thinning and dilatation
what are the causes of bronchiectasis?
congenital: CF, ciliary disorders (kartagner’s), PCD
post-infectious: measles, pertussis, recurrent bronchiolitis
how do you manage bronchiectasis?
conservative: airway clearance, chest physio and pulmonary rehab
medical:
abx - treat the isolated organism. >3 exac per year, long-term nebs antibiotics
surgical:
lobectomy: maybe considered for localised disease or to control haemoptysis
consider: bronchodilators (co-existant obstructive pathology) or steroids & itraconazole (ABPA)
what is the inheritance of CF?
most common autosomal recessive condition
affect 1:2000 live births, 1:25 carry a copy of the gene
diagnosis of CF?
sweat sodium and chloride >60 mmol/L
(chloride > sodium usually)
principles of managing CF?
lung
- chest physio - frequently family/carers know best. usually in the morning, often >1 x per day
- treat infections, prophylactic Abx, test for pseudomonas colonisation
- mucolytics (DNase alpha or hypertonic saline)
- bronchodilators
- yearly CXR
- extra: mutation-specific therapy ivacaftor and lumacaftor target the CFTR protein
GI
- pancreatic enzyme replacement (CREON)
- fat-soluble vitamin supplements (ADEK)
- ursodeoxycolic acid for impaired liver function
- cirrhosis = liver transplant
other
- CF-related diabetes
- osteoporosis
- genetic councilling/fertility
median age of survival in CF?
41 years in the UK, though baby born today would expect to live longer
what lymph nodes are affected in bronchial carcinoma?
mediastinal (cannot palpate), supraclavicular and axillary
differential diagnosis of nodule on CXR?
- malignancy (1ary or 2ary)
- abscess
- granuloma (TB or sarcoid, look for lymphadenopathy)
- carcinoid tumour, other benign neoplams (hamartoma)
what must be done in the work-up for curative lung tumour resection before surgery?
PET-CT for staging
- N0 no nodes
- N1 peribronchial or ipsilateral hilum
- N2 ipsilateral medistinum or subcarinal
- N3 contralateral mediastinum or hilum, scalene or subcarinal
what is the prognosis for patients with bronchial carcinoma?
NSCLC - 50% 2 year survival without spread, 10% with spread
SCLC - 3 months if untreated, 1-1.5 yrs if treated
what are the 5 ways aspergillus can affect the lung?
- asthma (present in 1-5% of asthmatics)
- allergic bronchopulmonary aspergillosis
- aspergilloma
- invasive aspergillosis
- extrinsic allergic alveolitis
what are some systemic disease that can present with asthma?
(not atopy)
GORD/reflux, vasculitides (polyarteritis nodosa, eGPA Churg-Strauss), ABPA
what are some complications of COPD?
lung
- infectious exacerbations
- fibrosis
- type II respiratory failure
- pneumothorax
- lung CA
systemic
- secondary polycythaemia
- cor pulmonale
beyond medical therapy, what is helpful in managing COPD?
smoking cessation
diet + supplements (often underweight)
pulmonary rehabilitation/exercise encouragement
LTOT - if resting hypoxaemia and successfully stopped smoking
diuretics (co-morbid heart failure)
vaccinations - influenza (all) and pneumococcus (>65 y/o)
what are the common signs of PE on ECG?
- sinus tachycardia
- right ventricular strain (inverted T waves in V1-4)
- right bundle branch block
don’t say S1 Q3 T3 first!
causes of transudative and exudative pleural effusions
transudate - cardiac failure, hypoalbuminaemia (liver and renal failure)
exudate - malignancy and pneumonia
where do you send samples of pleural fluid?
biochemistry
microbiology
cytology
need a paired sample of serum for protein and LDH
Light’s criteria and differentiating pleural effusions
transudate protein <25 g/L
exudate protein >35 g/L
25-35 g/L - pleural fluid protein/serum protein >0.5 = exudate
pleural fluid LDH/serum LDH >0.6 = exudate
what are some causes of cor pulmonale?
Lung parenchyma
- COPD
- bronchiectasis
- pulmonary fibrosis
pulmonary vasculature
- pulmonary embolism
- primary pulmonary hypertension
other - thoracic cage and neuromuscular abnormalities
what are the signs of cor pulmonale on chest examination?
- prominent P2
- right parasternal heave (RVH)
- right heart failure: raised JVP, pulsatile hepatomegaly, oedema
+/- pulmonary regurg = Graham Steel murmur (early diastolic)
+/- tricuspid regurg = pansystolic murmur
what are the indications for steroid treatment in sarcoidosis ?
parenchymal lung disease
uveitis
hypercalcaemia
neurologic or cardiac involvement
what are some causes of bihilar lymphadenopathy?
benign
- sarcoidosis
- tuberculosis
- hypersensitivity pneumonitis
- pneumoconioses (silica, beryllium)
malignant
- bronchial CA (stage N2-3)
- lymphoma/CLL
- histiocytosis x (langerhan’s cell histicocytosis)
what happens to the TLCO/KCO in IPF?
decreased
what are the treatment options for IPF?
supportive care: oxygen, pulmonary rehab, opiates and palliation
consideration of lung transplant and current clinical trial involvement
new: anti-fibrotic drugs nintedanib and pirfenidone starting to show promise
what is the correct term for a patient with a large thoracic volume on inspection when you are examining them?
barrel chest
cannot say ‘hyperexpanded’ becuase you have to measure the chest with a tape measure and compare this to a nomogram for that to be accurate
what are the most important findings when presenting intersitial lung disease?
- supplimental oxygen
- clubbing and cyanosis
- fine crackles (+/- apex or base)
what are the most important findings when presenting consolidation?
- bronchial breathing (+/- coarse crackles)
- dull to percussion
- increased vocal fremitus
what are the most important findings when presenting bronchiectasis?
- clubbing
- sputum
- coarse crackles
what are the most important findings when presenting pleural effusion?
- decreased breath sounds
- stoney dull to percussion
- decreased vocal fremitus
how do you describe the breathing pattern of somebody with COPD?
dyspnoeic, audible wheeze from the end of the bed
purse-lip breathing
prolonged expiratory phase
COPD does not cause clubbing.
what should be suspected in a patient with COPD and clubbing?
smoking can also cause cancer, which can cause clubbing
investigate for small cell lung CA
what is the pathophysiology of COPD?
smoking
- direct oxidative stress causes necrosis and apoptosis of the lung parenchyma
- activates resident macrophages and neutrophils of the airways to release elastases. proteolytic enzymes > anti-protease enzymes leads to destruction of compliant lung & airway tissue and obstruction
what are the causes of COPD and how does this relate to their histological distribution?
smoking - mixed centri-/panancinar
alpha1 anti-trypsin - panacinar
coal dust - centriacinar
what are the bugs of acute exacerbation of COPD?
- haemophilus influenzae*
- strep pneumo*
- moraxella catarrhalis*
what are the conditions for LTOT in COPD?
MUST
- stopped smoking - carboxyhaemoglobin < 3%
AND
- PaO2 < 7.3 kPa
OR
- PaO2 7.3-8.0 kPa with
- secondary polycythaemia
- pulmonary hypertension
- cor pulmonale
- nocturnal deoxygenation
what are the causes of bronchiectasis?
childhood infection
- tuberculosis
- pertussis
- measles
muco-ciliary dysfunction
- cystic fibrosis
- kartagner’s
- primary ciliary dyskinesia
bronchial obstruction
- endobronchial tumour
- foreign body aspiration
fibrosis
- idiopathic pulmonary fibrosis (long-standing)
- infection complicated by fibrosis
idiopathic
what is the gold standard diagnostic test for bronchiectasis?
high-resolution chest CT
what does the ‘signet ring sign’ represent? (CT)
signet ring sign = bronchiectasis
damaged and enlarged bronchus has a larger diameter than the adjacent blood vessel
what are the LRTI bugs for bronchiectasis?
- staphylococcus aureus*
- haemophilus influenzae*
- pseudomonas aeruginosa*
which antibiotic is suitable for treating legionella pneumonia?
clarithromycin
… macrolide > quinolone
which lung CA is associated with PHTrP?
which lung CA is associated with ectopic ACTH and ADH?
PTHrP = squamous cell carcinoma
ADH/ACTH/LEMS = small cell carcinoma
what is the rule for calculating the blood gas expected PaO2 from the FiO2?
[FiO2 (%) - 10] = expected PiO2 (kPa)
can also be done using the arterial-alveolar (A-a) oxygen gradient, but usually works out to just FiO2 - 10
what are the causes of intersitial lung disease/pulmonary fibrosis?
lung diseases
- IPF
- TB/sarcoid
- EAA
- COPD
- pneumoconioses
- beryllium
- coal
- silica
- asbestos
rheumatological disease
- SLE
- rheumatoid arthritis
- MCTD
- systemic sclerosis
drugs
- amiodarone
- methotrexate
- bleomycin
- gold
- nitrofurantoin
vasculitis
- wegener’s
- polyarteritis nodosa
- goodpasture’s
- churg-strauss
