resp Flashcards
Features of life threatening asthma?
- PEFR <33%
- SpO2 <92%
- Normal pCO2 (4.6-6.0)
- Silent chest, cyanosis, feeble resp effort
- Brady/ hypotension
- exhaustion/ confusion/ coma
Features of Severe Asthma?
- PEFR 33-50%
- can’t complete sentences
- RR >25
- HR >110
Features of Moderate asthma?
- PEFR 50-75%
- speech normal
- RR <25
- HR <110
Near-fatal asthma?
raised pCO2 -> requiring mechanical ventilation
CXR in asthma not routinely recommended unless…?
- life threatening asthma
- Suspected pneumothorax
- failure to respond to treatment
When do BTS guidelines recommend ABG for asthma attacks?
oxygen sats <92%
Pathophysiology of Alpha-1 antitrypsin deficiency
- A1AT protects against enzymes such as neutrophil elastase.
- lack of A1AT (protease inhibitor normally produced by liver) causes emphysema
Genetics of Alpha-1 antitrypsin deficiency
- auto recessive
- chr 14
features of alpha-1 antitrypsin deficiency?
- lungs: panacinar emphysema, most marked in lower lobes
- liver: cirrhosis/ HCC in adults, cholestasis in children
Ix of Alpha-1 antitrypsin deficiency?
- A1AT concentrations
- spirometry - obstructive picture
Management of Alpha-1 antitrypsin deficiency?
- no smoking
- supportive: bronchodilators, physio
- IV A1AT protein concentrates
- Surgery: lung volume reduction surgery, lung transplant
Features of cryptogenic organizing pneumonia?
- diffuse interstitial lung disease
- not assoc w smoking
- cough, SOB, fever, malaise
- elevated ESR/ CRP
- Bilateral patch/ ground glass opacities
- TF reduced
Treatment of cryptogenic organizing pneumonia?
watch and wait if mild, if severe -high dose oral steroids
most common organism isolated from patients with bronchiectasis?
haemophilus influenzae
Management of bronchiectasis: what is most important for long term control of symptoms?
inspiratory muscle training + postural drainage
Bronchoscopy showing “cherry red ball”
Lung Carcinoid
features of lung carcinoid?
- typical age 40-50y
- smoking not assoc
- slow growing e.g long hx of cough, recurrent haemoptysis
- often centrally located + not seen on CXR
- cherry red ball often seen on bronchoscopy
management of lung carcinoid?
surgical resection
1st line for moderate or severe obstructive sleep apnoea?
CPAP
1st line mx of Chlamydia psittaci?
doxycycline
management of pleural plaques?
- nothing, no follow up needed as pleural plaques are benign and do not undergo malignant change
asbestosis causes fibrosis in what part of the lung?
lower lobe fibrosis
Contraindications to lung surgery?
- stage IIIb or IV (i.e. metastases present)
- FEV1 < 1.5 litres (general cut off)
- malignant pleural effusion
- tumour near hilum
- vocal cord paralysis
- SVC obstruction
Causes of lower zone pulmonary fibrosis?
- idiopathic
- most connective tissue disorders e.g. SLE
- drug-induced: amiodarone, bleomycin, methotrexate
- asbestosis
Causes of Upper zone pulmonary fibrosis?
CHARTS:
C - Coal worker's pneumoconiosis H - Histiocytosis/ hypersensitivity pneumonitis A - Ankylosing spondylitis R - Radiation T - Tuberculosis S - Silicosis/sarcoidosis
management of primary pneumothorax if rim of air >2cm OR SOB?
needle aspiration.
- > if this fails, then chest drain
- > advise STOP smoking!
management of secondary pneumothorax if rim >2cm and/or SOB?
- chest drain insertion
management of secondary pneumothorax if rim of air is 1-2cm?
aspiration
management of secondary pneumothorax if rim of air <1cm?
oxygen + admit for 24h
What is KCO (transfer co-efficient of carbon monoxide) and how is it affected in lung disease?
KCO is a measure of the efficiency of gas exchange into the blood stream. It is reduced if the lungs are damaged and increased if there is additional blood in the lungs to remove carbon monoxide.
What is TLCO (Transfer factor for carbon monoxide)?
TLCO = KCO x Alveolar volume
- The transfer factor describes the rate at which a gas will diffuse from alveoli into blood. Carbon monoxide is used to test the rate of diffusion.
Causes of raised TLCO (Transfer factor for carbon monoxide)? ie. increased rate of gas diffusion from alveoli into blood
- asthma
- pulmonary haemorrhage (Wegener’s, Goodpasture’s)
- left-to-right cardiac shunts
- polycythaemia
- hyperkinetic states
- male gender, exercise
Causes of reduced TLCO (Transfer factor for carbon monoxide)? ie. reduced rate of gas diffusion from alveoli into blood
- pulmonary fibrosis
- pneumonia
- PE
- pulmonary oedema
- emphysema
- anaemia
- low cardiac output
Causes of conditions which increase KCO (increased efficiency of gas exchange) but have a normal/ reduced TLCO (ie. reduced rate of gas diffusion from alveoli into blood- due to reduced alveolar volume) ?
- pneumonectomy/lobectomy
- scoliosis/kyphosis
- neuromuscular weakness
- ankylosis of costovertebral joints e.g. ankylosing spondylitis
Features of silicosis?
- upper zone lung fibrosis
- ‘egg-shell’ calcification of the hilar lymph nodes
MOA of varenicline?
nicotinic receptor partial agonist
MOA of bupropion?
a norepinephrine and dopamine reuptake inhibitor, and nicotinic antagonist
CI for bupropion?
epilepsy (small risk of seizures), pregnancy, breast feeding, eating disorder
Smoking cessation for pregnancy women?
1st line: CBT
- nicotine replacement therapy
Diagnosistic test for obstructive sleep apnoea?
polysomnography (sleep studies)
Lofgrens syndrome?
acute form of sarcoidosis characterised by bilateral hilar lymphadenopathy (BHL), erythema nodosum, fever and polyarthralgia
Heerfordt’s syndrome (uveoparotid fever) ?
parotid enlargement, fever and uveitis secondary to sarcoidosis
Ix findings of extrinsic allergic alveolitis?
- imaging: upper/mid-zone fibrosis
- bronchoalveolar lavage: lymphocytosis
- serologic assays for specific IgG antibodies
- blood: NO eosinophilia
hypercalcaemia in sarcoidosis?
macrophages inside the granulomas cause an increased conversion of vitamin D to its active form (1,25-dihydroxycholecalciferol)
oxygen dissociation curve - shift to left =?
decreased oxygen delivery to tissues
oxygen dissociation curve - shift to right =?
increased oxygen delivery to tissues
factors causing oxygen dissociation curve to shift left?
- everything that decreases oxygen delivery to tissues
HbF, methaemoglobin, carboxyhaemoglobin
Low [H+] (alkali)
Low pCO2
Low 2,3-DPG
Low temperature
factors causing oxygen dissociation curve to shift right?
- causing raised oxygen delivery
Raised [H+] (acidic)
Raised pCO2
Raised 2,3-DPG*
Raised temperature
organism implicated in malt workers lung? (part of EAA)
Aspergillus clavatus
Organism implicated in farmers lung (part of EAA)?
spores of Saccharopolyspora rectivirgula from wet hay
organism implicated in bird fanciers lung (part of EAA)?
avian proteins from bird droppings
organism implicated in mushroom workers lung (part of EAA)?
thermophilic actinomycetes
paraneoplastic features of small cell lung ca?
- ADH -> Hypona
- ACTH -> Cushings
- Lambert Eaton syndrome
paraneoplastic features of squamous cell lung ca?
PTH-related peptide, clubbing, hypertrophic pulmonary osteoarthropathy, ectopic TSH -> Hyperthyroid
pleural effusion - pleural fluid showing low glucose assoc w?
rheumatoid arthritis, TB
pleural effusion - pleural fluid showing raised amylase assoc w?
pancreatitis, oesophageal perforation
pleural effusion - pleural fluid showing heavy blood staining assoc w?
mesothelioma, Pulmonary embolism, TB
Genetics of Cystic fibrosis?
Chr 7, auto recessive, CFTR gene
catamenial pneumothorax
cause of 3-6% of spontaneous pneumothoraces occurring in menstruating women. It is thought to be caused by endometriosis within the thorax
Paraneoplastic features of lung adenocarcinoma?
gynaecomastia, Hypertrophic pulmonary osteoarthropathy
1st line management of COPD?
SABA/ SAMA
what features do NICE suggest to determine whether pt with suspected COPD has asthmatic/ steroid responsive features?
- any previous diagnosis of asthma/ atopy
- High eosinophil count in FBC
- Peak flow: substantial diurnal variation in PEF (>/= 20%)
- substantial variation in FEV1 over time (>400mL)
management of COPD if no asthmatic features?
- add LABA/ LAMA
- if on SAMA, discontinue and switch to SABA
management of COPD if asthmatic features?
- LABA + ICS
- then Triple therapy ie. LAMA + LABA + ICS
- if on SAMA, discontinue and switch to SABA
what investigations to do before starting oral prophylactic antibiotic therapy in COPD?
- stop smoking
- CT thorax to exclude bronchiectasis
- sputum culture to exclude atypical infections/ TB
- LFTs + ECG to exclude QT prolongation as azithromycin can prolong QT
features of Loffler’s syndrome
- thought to be due to parasites such as ascaris lumbricoides causing an alveolar reaction
- transient CXR shadowing and blood eosinophilia
- fever, cough, night sweats
- generally self limiting, <2 weeks
mx of allergic bronchopulmonary aspergillosis
oral steroids.
2nd line - itraconazole
Contraindications for varenicline?
pregnancy/ breast feeding.
caution- depression/ self harm
features of Churg Strauss / eosinophilic granulomatosis with polyangiitis?
asthma, blood eosinophilia, paranasal sinusitis, mono neuritis multiplex, pANCA +
what drug class might precipitate Churg Strauss?
Leukotriene receptor antagonists
genotype of homozygous A1AT deficiency leading to 50% and 10% normal A1AT levels?
50% of normal: piSS
10% of normal: PiZZ
Normal: PiMM
features of Kartagener’s?
- dextrocardia/ situs inversus
- bronchiectasis
- recurrent sinusitis
- sub fertility
most common chemical causing occupational asthma?
isocyanates
- example occupations include spray painting and foam moulding using adhesives
Investigation of choice for assessing compression of upper airway?
Flow volume loop
factors associated with poor prognosis in sarcoidosis?
- insidious onset, symptoms > 6 months
- absence of erythema nodosum
- extrapulmonary manifestations: e.g. lupus pernio, splenomegaly
- CXR: stage III-IV features
- black people
prophylaxis medication to prevent acute mountain sickness?
acetazolamide (a carbonic anhydrase inhibitor)
Management of high altitude cerebral oedema?
descent, dexamethasone
Management of high altitude pulmonary oedema?
descent, oxygen if avail.
- nifedipine, dexamethasone, acetazoleamide, phosphodiesterase type V inhibitor* (all work by reducing systolic pulmonary artery pressure)
what is a specific Cystic fibrosis contraindication to lung transplantation?
chronic infection with Bulrkholderia cepacia
Diet advice in Cystic fibrosis?
High calorie, high fat with pancreatic enzyme supplementation with every meal
Lumacaftor/ Ivacaftor?
- used to treat Cystic fibrosis
- lumacaftor increases the number of CFTR proteins transported to cell surface
- ivacaftor is a potentiator of CFTR, increasing the probability that the defective channel will be open
Indication for steroid treatment in Sarcoidosis?
- patients with chest x-ray stage 2 or 3 disease + symptomatic.
- hypercalcaemia
- eye, heart or neuro involvement
CXR findings in idiopathic pulmonary fibrosis?
bilateral interstitial shadowing (typically small, irregular, peripheral opacities - ‘ground-glass’ -> later progressing to ‘honeycombing’)
CXR 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
How does silica lead to TB?
Silica is a Risk factor for developing TB as silica is toxic to macrophages
what type of lung cancer would be most likely to cavitate?
squamous cell lung ca
causes of bilateral hilarity lymphadenopathy?
sarcoidosis, TB.
- lymphoma/other malignancy
- pneumoconiosis e.g. berylliosis
- fungi e.g. histoplasmosis, coccidioidomycosis