Respiratory Flashcards
What gender is idiopathic pulmonary fibrosis more common in?
Men (twice as likely).
What are the criteria for LTOT in COPD patients?
< 7.3 kPa or to those with a pO2 of 7.3 - 8 kPa and one of the following: secondary polycythaemia nocturnal hypoxaemia peripheral oedema pulmonary hypertension
ABGs results are based on 2 results, 3 week apart
What must be done before offering azithromycin in patients with COPD.
Only offered if having frequent exacerbations despite optimum therapy in patients who DO NOT SMOKE.
Should have CT to exclude bronchietasis.
Sputum cultures for TB and atypical infections e.g. mycoplasma.
LFTs and ECG (prolongs QTc)
What are the features of cor pulmonale?
Features include peripheral oedema, raised jugular venous pressure, systolic parasternal heave, loud P2.
What is the treatment of cor pulmonale?
Loop diuretics +/- LTOT
ACE-inhibitors, calcium channel blockers and alpha blockers are not recommended.
What things improve survival in COPD
smoking cessation - the single most important intervention in patients who are still smoking
long term oxygen therapy in patients who fit criteria
lung volume reduction surgery in selected patients
What happens in ARDS?
Acute respiratory distress syndrome (ARDS) is caused by the increased permeability of alveolar capillaries leading to fluid accumulation in the alveoli, i.e. non-cardiogenic pulmonary oedema.
What are the causes of ARDS?
infection: sepsis, pneumonia massive blood transfusion trauma smoke inhalation acute pancreatitis cardio-pulmonary bypass
What are the criteria for ARDS?
acute onset (within 1 week of a known risk factor)
pulmonary oedema: bilateral infiltrates on chest x-ray (‘not fully explained by effusions, lobar/lung collapse or nodules)
non-cardiogenic (pulmonary artery wedge pressure needed if doubt)
pO2/FiO2 < 40kPa (200 mmHg)
What is the main role of alpha 1 antitrypsan
it is a protease inhibitor
Where is A1AT produced?
liver
What gene is A1AT deficiency located on
chromosome 14
What type of inheritance is A1AT deficiency
autosomal recessive
Outline the genotypes in alpha1 antitrypsan deficiecny
Normal = PiMM
PiSS (50 percent normal levels)
PiZZ (10 percent normal levels)
Patients who manifest the disease phenotypicall usually have PiZZ genotype
What does A1AT defiency result in
Emphysema
Liver cirrhosis
Hepatocellular carcinoma
What type of lung cancer is most commonly associated with cavitating lesions?
Squamous
What is the treatment of OSA
Weight loss
First line in moderate/severe is CPAP overnight
Intra oral devices can be uses if CPAP is not tolerated or in very mild cases
Outline the management of a primary pneumothorax
f the rim of air is < 2cm and the patient is not short of breath then discharge should be considered
otherwise, aspiration should be attempted
if this fails (defined as > 2 cm or still short of breath) then a chest drain should be inserted
Outline the management of a secondary pneumothorax
if the patient is > 50 years old and the rim of air is > 2cm and/or the patient is short of breath then a chest drain should be inserted.
otherwise aspiration should be attempted if the rim of air is between 1-2cm. If aspiration fails (i.e. pneumothorax is still greater then 1cm) a chest drain should be inserted. All patients should be admitted for at least 24 hours
if the pneumothorax is less the 1cm then the BTS guidelines suggest giving oxygen and admitting for 24 hours
What is the mechanism of varenicline?
Used to help smoking cessation.
Nicotinic receptor partial agonist.
How does sarcoidosis cause hypercalcaemia
Sarcoidosis mainly causes hypercalcaemia through forming increased concentrations of calcitriol, the active component of vitamin D. This is as a result of increased activity of 1α hydroxylase produced by the sarcoid macrophages.
What is sarcoidosis
multisystem disorder of unknown aetiology characterised by non-caseating granulomas. It is more common in young adults and in people of African descent
Name some characteristic features of sarcoidosis
acute: erythema nodosum, bilateral hilar lymphadenopathy, swinging fever, polyarthralgia
insidious: dyspnoea, non-productive cough, malaise, weight loss
skin: lupus pernio
hypercalcaemia: macrophages inside the granulomas cause an increased conversion of vitamin D to its active form
What is Lofgrens syndrome
acute form of sarcoidosis characterised by bilateral hilar lymphadenopathy (BHL), erythema nodosum, fever and polyarthralgia. It usually carries an excellent prognosis
What is Mikulicz syndrome
enlargement of the parotid and lacrimal glands due to sarcoidosis, tuberculosis or lymphoma
What is Heerfordt’s syndrome
parotid enlargement, fever and uveitis secondary to sarcoidosis
What paraneoplastic syndromes are associated with small cell lung cancer
SIADH Cushings syndrome (high ACTH) Lambert Eaton (antibodies against presynaptic calcium channels at the NMJ)
What paraneoplastic features are associated with squamous cell lung cancer
parathyroid hormone-related protein (PTH-rp) secretion causing hypercalcaemia
clubbing
hypertrophic pulmonary osteoarthropathy (HPOA)
hyperthyroidism due to ectopic TSH
What paraneoplastic features are associated with adenocarcinoma of the lung?
gynaecomastia
hypertrophic pulmonary osteoarthropathy (HPOA)
Describe the chest x ray stages in sarcoidosis
stage 0 = normal
stage 1 = bilateral hilar lymphadenopathy (BHL)
stage 2 = BHL + interstitial infiltrates
stage 3 = diffuse interstitial infiltrates only
stage 4 = diffuse fibrosis
What is the most common cause of occupational asthma?
Isocyanates
what is loffler’s syndrome
transient CXR shadowing and blood eosinophilia
thought to be due to parasites such as Ascaris lumbricoides causing an alveolar reaction
presents with a fever, cough and night sweats which often last for less than 2 weeks.
generally a self-limiting disease
What HLA is associated with bronchietasis
DR1
Which HLA is associated with SLE
DR2
What is HLA-DR3 associated with
autoimmune hepatitis, primary Sjogren syndrome, type 1 diabetes Mellitus, SLE
what is associated with HLA DR4
rheumatoid arthritis, type 1 diabetes Mellitus
What is associated with HLa-B27
ankylosing spondylitis, postgonococcal arthritis, acute anterior uveitis
give causes of bronchietasis
post-infective: tuberculosis, measles, pertussis, pneumonia
cystic fibrosis
bronchial obstruction e.g. lung cancer/foreign body
immune deficiency: selective IgA, hypogammaglobulinaemia
allergic bronchopulmonary aspergillosis (ABPA)
ciliary dyskinetic syndromes: Kartagener’s syndrome, Young’s syndrome
yellow nail syndrome
what features can be associated with mycoplasma pneumonia
erythema mutiforme
autoimmune haemolytic anaemia
what type of pneumonia classically occurs after flu
staph aureus
what pneumonia is classically caused by aspiration
klebsiella
what features are ‘classic’ of klebsiella pneumonia
cavitating
red currant jelly sputum
what lung causes fibrosis in the lower zone
idiopathic pulmonary fibrosis
most connective tissue disorders (except ankylosing spondylitis) e.g. SLE
drug-induced: amiodarone, bleomycin, methotrexate
asbestosis
what lung fibrosis occurs in the upper zone
hypersensitivity pneumonitis (also known as extrinsic allergic alveolitis)
coal worker’s pneumoconiosis/progressive massive fibrosis
silicosis
sarcoidosis
ankylosing spondylitis (rare)
histiocytosis
tuberculosis
what medication can precipitate Churg strauss
montelukast
at what pH of fluid would you insert a chest drain
7.2
what is the mechanism of action of montelukast
leukotriene receptor antagonist
what is allergic bronchopulmonary aspergillosis
results from an allergy to Aspergillus spores. In the exam questions often give a history of bronchiectasis and eosinophilia.
what are the major diagnostic criteria for allergic bronchopulmoanry aspergillosis
Clinical features of asthma Proximal bronchiectasis Blood eosinophilia Immediate skin reactivity to Aspergillus antigen Increased serum IgE (>1000 IU/ml)
what are the minor diagnotic criteria for allergic bronchopulmonary aspergillosis
Fungal elements in sputum
Brown flecks in sputum
Delayed skin reactivity to fungal antigens
what causes raised TLCO
asthma pulmonary haemorrhage (Wegener's, Goodpasture's) left-to-right cardiac shunts polycythaemia hyperkinetic states male gender, exercise
what causes lower TLCO
pulmonary fibrosis pneumonia pulmonary emboli pulmonary oedema emphysema anaemia low cardiac output
what is KCO
transfer coeffient of gas exchange corrected for lung volume
What conditions may cause an increased KCO with a normal or reduced TLCO
pneumonectomy/lobectomy
scoliosis/kyphosis
neuromuscular weakness
ankylosis of costovertebral joints e.g. ankylosing spondylitis
what classically causes ‘egg shell calcification’ on CT
silicosis
exposure to what material increases your risk of TB
silicosis
what is the most common side effect of varenciline
nausea
what is normal pulmonary arterial pressure?
less than 25 at rest, 30 if exercising
give some skin disorders associated with TB
lupus vulgaris (accounts for 50% of cases)
erythema nodosum
scarring alopecia
scrofuloderma: breakdown of skin overlying a tuberculous focus
verrucosa cutis
gumma
what cell secrete surfactant
type 2 pneumocytes
