Resp Flashcards
Pneumothorax
when does it occur
when air gets into the pleural space separating the lung from the chest wall
Pneumothorax
Causes
- spontaneous
- trauma
- iatrogenic: lung biopsy, mechanical ventilation or central line insertion
- lung pathology: infection, asthma or COPD
Pneumothorax
inx of choice for a simple pneumothorax
erect chest x-ray
Pneumothorax
chest x-ray results
area between lung tissue and chest wall where there are no lung markings
line demarcating the edge of the lung where the lung markings ends and the pneumothorax begins
Pneumothorax
how to measure the size of the pneumothorax according to BTS guidelines
measure horizontally from the lung edge to the inside of the chest wall at the level of the hilum
Pneumothorax
what can be used to detect a small pneumothorax that is too small to see on CXR or be used to accurately assess the size of the pneumothorax
CT thorax
Pneumothorax
mnx if no SOB and <2cm rim of air on CXR
no trx as it will spontaneously resolve
follow up in 2-4w
Pneumothorax
mnx if SOB and/or >2cm rim of air on CXR
aspiration and reassessment
Pneumothorax
what happens if aspiration mnx fails twice
it will require a chest drain
Pneumothorax
who will require a chest drain
unstable patient
bilateral or secondary pneumothoraces
if aspiration fails twice
Pneumothorax
what causes a tension pneumothorax
trauma to chest wall that creates a one-way valve that lets air in but not out of the pleural space
during inspiration, air is drawn into the pleural space and during expiration, the air is trapped in the pleural space
Pneumothorax
why is lot of air in the pleural space dangerous in a tension pneumothorax
it creates pressure inside the thorax that will push the mediastinum across, kink the big vessels in the mediastinum and cause cardiorespiratory arrest
Pneumothorax
signs of tension pneumothorax (5)
- tracheal deviation away from the side of pneumothorax
- reduced air entry to affected side
- increased resonant to percussion on affected side
- tachycardia
- hypotension
Pneumothorax
mnx of a tension pneumothorax
insert a large bore cannula into the 2nd ICS in the midclavicular line
then chest drain for definitive mnx
Pneumothorax
where are chest drains inserted
into the ‘triangle of safety’
obtain CXR to check positioning
Pneumothorax
what forms the ‘triangle of safety’
- 5th ICS (or inferior nipple line)
- mix-axillary line (lateral edge of latissimus dorsi)
- anterior axillary line (lateral edge of pec major)
Pneumothorax
why is the needle inserted just above the rib in a chest drain
to avoid the neurovascular bundle that runs below the rib
Lung Function Tests
what test is used to establish objective measures of lung function
spirometry
Lung Function Tests
what does spirometry involve
different breathing exercises into a machine that measures volumes of air and flow rates and produces a report
Lung Function Tests
what does reversibility testing involve
giving a bronchodilator (eg salbutamol) prior to repeating the spirometry to see the impact this has on the results
Lung Function Tests
what is FEV1
forced expiratory volume in 1 second
the amount of air a person can exhale as fast as they can in 1 sec
it will be reduced if there is any OBSTRUCTION to the air flow out of the lungs
Lung Function Tests
what is FVC
forced vital capacity
the total amount of air a person can exhale after a full inhalation
measure of the total volume of air the person can take into their lung s
it will be reduced if there is any RESTRICTION on the capacity of their lungs
Lung Function Tests
what will be reduced if there is any obstruction
FEV1
Lung Function Tests
what will be reduced if there is any restriction
FVC
Lung Function Tests
how can obstructive lung disease be diagnosed
when FEV1 is less than 75% of FVC
FEV1 : FVC ratio <75%
Lung Function Tests
in asthma, what is the obstruction due to
narrowed airway due to bronchoconstriction
Lung Function Tests
in COPD, what is the obstruction due to
chronic airway and lung damage
Lung Function Tests
the difference between asthma and COPD
test for reversibility of the obstruction by giving a bronchodilator.
the obstructive picture is typically reversible in asthma
Lung Function Tests
how can restrictive disease be diagnosed
FEV1 and FVC are equally reduced
and FEV1 : FVC ratio > 75%
Lung Function Tests
what is restrictive lung disease
where there is restriction to the ability of the lungs to expand and take air in
Lung Function Tests
causes of restrictive lung disease (4)
- interstitial lung disease
- neurological (eg MND)
- scoliosis or chest deformity
- obesity
Lung Function Tests
what is a peak flow a measure of
the ‘peak’ or fastest point, of a person’s expiratory flow of air
PEFR: peak expiratory flow rate
Lung Function Tests
what is the predicted peak flow based on
sex, height and age
COVID-19
where were the first cases reported
Wuhan, China
COVID-19
which animal did it originate
bats
COVID-19
clinical features (3)
- fever
- dry cough
- SOB
- nausea
- headache
- sore throat
- diarrhoea
- loss of smell/taste
COVID-19
how long is the incubation period
2-10d
COVID-19
severe covid disease pathogenesis
thought to be due to hyper-inflammatory response to the virus
raised inflammatory biomarkers (IL-2R, IL-6, IL-10 and TNFa)
COVID-19
what is death usually from
- respiratory failure
- multi-organ failure (heart, liver, kidney)
- neuro complications (stroke)
COVID-19
RFs for severe covid disease
- older age
- male sex
- comorbidities (chronic heart/lung disease, HTN, DM)
- high BMI
- lower socio-economic level
COVID-19
prognostic markers for severe covid disease
- present with tachypnoea, tachycardia, low paO2
- very low lymphocyte count <0.5 x 10(9)/ml
- raised CRP and ferritin (inflammatory markers)
- abnormal clotting: coagulopathy with increased D-dimers and fibrinogen, often leading to PE)
COVID-19
what predicts poor outcomes
hyperinflammation
COVID-19
distinct features of hyperinflammation
- earlier onset of ARDS
- prominent thrombo-embolic features
- relatively low levels of cytokines + ferritin
COVID-19
why is being male a RF for severe disease
- innate (adaptive) immune function enhanced in females
- ACE2 receptor distribution
- Male mice accumumlated inflammatory macrophages
COVID-19
what ethnicity is a RF for severe disease
South Asian
COVID-19
genetic factors contributing to critical illness
- OAS genes
- DPP9 gene variants
- low IFNAR2 and elevated TYK2
- Baricitinib
COVID-19
respiratory support for mnx of severe disease
- supplementary O2
- CPAP
- Mechanical ventilation
- Proning
- monitor for PE, secondary infection
COVID-19
medications for mnx of severe disease
- Dexamethasone
- Remdesivir (anti-viral therapy)
- Tociluzamab (monoclonal antibody to IL-6)
- Anakinra (monoclonal antibody to IL-1 for hyper-inflammation)
- Antibody therapy (Regeneron/Ronapreve)
COVID-19
what can be given for pts developing lung fibrosis
additional high dose steroids
COVID-19
how long do covid symptoms last
Zoe data shows 1/10 are sick for 3w or more
COVID-19
what is the most common cause of ‘breathlessness’ after covid
dysfunctional breathing: umbrella term for hyperventilation, disordered breathing, mechanical changes
Pleural Effusion
what is it
a collection of fluid in the pleural cavity
it can be exudative or transudative
Pleural Effusion
exudative meaning
high protein count
>3g/dL
Pleural Effusion
transudative meaning
there is a relatively lower protein count
<3g/dL
Pleural Effusion
what causes it to be exudative
inflammation results in protein leaking out of the tissues into the pleural space (ex- meaning moving out of)
Pleural Effusion
exudative causes
inflammation causes:
- lung cancer
- pneumonia
- RA
- TB
Pleural Effusion
what causes it to be transudative
relate to fluid moving across into the pleural space (trans- meaning moving across)
Pleural Effusion
transudative causes
fluid shifting causes:
- congestive cardiac failure
- hypoalbuminaemia
- hypothyroidism
- Meig’s syndrome
Pleural Effusion
what is Meig’s syndrome
right sided pleural effusion with ovarian malignancy
Pleural Effusion
presentation (4)
- SOB
- dullness to percussion over the effusion
- reduced breath sounds
- tracheal deviation away from the effusion
Pleural Effusion
inx
- CXR
- pleural fluid sample by aspiration or chest drain: protein count, cell count, pH, glucose, LDH, microbiology testing
Pleural Effusion
what will the CXR show
- blunting of the costophrenic angle
- fluids in the lung fissures
- larger effusions have a meniscus: curving upwards where it meets the chest wall and mediastinum
- tracheal and mediastinal deviation if massive effusion
Pleural Effusion
trx if small effusion
conservative mnx
will resolve with trx of underlying cause
Pleural Effusion
trx for larger effusions
pleural aspiration:
chest drain
Pleural Effusion
what does pleural aspiration involve
sticking a needle in and aspirating fluid
temporarily relieves pressure but the effusion may recur
repeated aspiration may be required
Pleural Effusion
what is an empyema
where there is an infected pleural effusion
Pleural Effusion
when should you suspect an empyema
in a pt who has improving pneumonia but new ongoing fever
Pleural Effusion
what would pleural aspiration show in empyema
pus
acidic pH <7.2
low glucose
high LDH
Pleural Effusion
how are empyemas treated
by chest drain to remove pus
abx
Interstitial lung disease
what is it
an umbrella term to describe conditions that affect the lung parenchyma causing inflammation and fibrosis
Interstitial lung disease
what is fibrosis
the replacement of the normal elastic and functional lung tissue with scar tissue that is stiff and does not function effectively
Interstitial lung disease
how to make a diagnosis
clinical features + high resolution CT scan of the thorax
when unclear, lung biopsy can be used for histology
Interstitial lung disease
what does high resolution CT scan show
ground glass appearance
Interstitial lung disease
what makes the prognosis poor
damage is irreversible
Interstitial lung disease
mnx
generally supportive:
- treat underlying cause
- home O2 if hypoxic at rest
- stop smoking
- physio + pulmonary rehab
- pneumococcal + flu vaccine
- advanced care planning and palliative care if appropriate
- lung transplant perhaps
Interstitial lung disease
sx of idiopathic pulmonary fibrosis
- insidious onset of SOB
- dry cough >3m
Interstitial lung disease
whom does idiopathic pulmonary fibrosis usually affect
adults >50 years old
Interstitial lung disease
signs in idiopathic pulmonary fibrosis
- bibasal fine inspiratory crackles
- finger clubbing
Interstitial lung disease
prognosis of idiopathic pulmonary fibrosis
poor with a life expectancy of 2-5yrs from diagnosis
Interstitial lung disease
which 2 medications are licensed that can slow the progression of the idiopathic pulmonary fibrosis
- Pirfenidone
- Nintedanib
Interstitial lung disease
Idiopathic Pulmonary Fibrosis: what is Pirfenidone
an antifibrotic and anti-inflammatory
Interstitial lung disease
Idiopathic Pulmonary Fibrosis: what is Nintedanib
a monoclonal antibody targeting tyrosine kinase
Interstitial lung disease
what drugs can cause pulmonary fibrosis
MANC
- amiodarone
- cyclophosphamide
- methotrexate
- nitrofurantoin
Interstitial lung disease
what conditions can pulmonary fibrosis occur secondary to?
- alpha-1 antitripsin deficiency
- RA
- SLE
- systemic sclerosis
Interstitial lung disease
What is hypersensitivity pneumonitis?
aka extrinsic allergic alveolitis
a type III hypersensitivity reaction
to an environmental allergen
that causes parenchymal inflammation
and destruction in people that are sensitive to that allergen
Interstitial lung disease
Hypersensitivity Pneumonitis: what does bronchoalveolar lavage involve?
collecting cells from the airways during bronchoscopy
by washing the airways with fluid
then collecting that fluid for testing
Interstitial lung disease
Hypersensitivity Pneumonitis: what will the bronchoalveolar lavage show
raised lymphocytes and mast cells
Interstitial lung disease
Hypersensitivity Pneumonitis mnx
- removing the allergen
- giving oxygen where necessary
- steroids
Interstitial lung disease
Hypersensitivity Pneumonitis: reaction to bird droppings
Bird-fanciers lung
Interstitial lung disease
Hypersensitivity Pneumonitis: reaction to mouldy spores in hay
farmers lung
Interstitial lung disease
Hypersensitivity Pneumonitis: reaction to specific mushroom antigens
mushroom workers’ lung
Interstitial lung disease
Hypersensitivity Pneumonitis: reaction to mould on barley
malt workers lung
Interstitial lung disease
what is Cryptogenic organising pneumonia
previously known as bronchiolitis obliterans organising pneumonia
focal area of inflammation of the lung tissue
Interstitial lung disease
Cryptogenic Organising Pneumonia: cause
idiopathic or triggered by: - infection - inflammatory disorders - medications - radiation - environmental toxins - allergens
Interstitial lung disease
Cryptogenic Organising Pneumonia: presentation
very similar to infectious pneumonia:
- SOB
- cough
- fever
- lethargy
focal consolidation on CXR
Interstitial lung disease
Cryptogenic Organising Pneumonia: definitive inx
lung biopsy
Interstitial lung disease
Cryptogenic Organising Pneumonia: trx
systemic corticosteroids
Interstitial lung disease
what is asbestosis
lung fibrosis related to the inhalation of asbestos
Interstitial lung disease
Asbestosis: what makes it fibrogenic
it causes lung fibrosis.
Interstitial lung disease
Asbestosis: what makes it oncogenic
it causes cancer
Interstitial lung disease
Asbestosis: what problems does asbestos inhalation cause
- lung fibrosis
- pleural thickening and pleural plaques
- adenocarcinoma
- mesothelioma
PE
what is it
where a blood clot (thrombus) forms in the pulmonary arteries
PE
what are DVTs and PEs collectively known as
VTE
PE
what are the RFs for developing a DVT or PE (9)
- immobility
- recent surgery
- long haul flights
- pregnancy
- hormone therapy with oestrogen
- malignancy
- polycythaemia
- SLE
- thrombophilia
PE
if pts are at increased risk of VTE, what should they receive
prophylaxis with LMWH e.g. enoxaparin
anti-embolic compression stockings
PE
when would LMWH (e.g. enoxaparin) be contraindicated
- active bleeding
- existing anticoagulation with warfarin or NOAC
PE
what is the main CI for compression stockings
significant peripheral arterial disease
PE
presenting features
- SOB
- cough with or without blood
- pleuritic chest pain
- hypoxia
- tachycardia
- reduced RR
- low grade fever
- haemodynamic instability causing hypotension
what score predicts the risk of a pt actually having a DVT or PE
Wells Score
VTE
if the Wells score is ‘likely’, what next?
perform a CT pulmonary angiogram
VTE
if the Wells score is ‘unlikely’, what next?
perform a d-dimer and if +ve, perform a CTPA
PE
what are the 2 main options for establishing a definitive dx
- CTPA
or
- ventilation perfusion scan
PE
when would you use a VQ scan instead of a CTPA
in pts with renal impairment, contrast allergy or at risk from radiation
PE
what may the ABG show and why
respiratory alkalosis
high RR causes them to ‘blow off’ extra CO2 so the blood becomes alkalotic
what are the only 2 causes of respiratory alkalosis
- PE
2. hyperventilation syndrome
on an ABG, what is the difference between a PE and hyperventilation syndrome
PE will have a low pO2 whereas pts w/ hyperventilation syndrome will have a high pO2
PE
initial mnx
apixaban or rivaroxaban started immediately if suspected VTE
before confirming dx
alternative: LMWH (enoxaparin, dalteparin) if unsuitable or in antiphospholipid syndrome
PE
what are the options for long term anticoagulation in VTE
warfarin, NOAC or LMWH
PE
when switching to warfarin, how long should you continue LMWH for
5 days
or until the INR is 2-3 for 24 hours
PE
what are the main DOACs
apixaban
dabigatran
rivaroxaban
PE
what is the 1st line trx in pregnancy or cancer
LMWH
PE
how long should pt continue long term anticoagulation if there is an obvious reversible cause
3m
PE
how long should pt continue long term anticoagulation if the cause is unclear; there is recurrent VTE or there is an irreversible cause such as thrombophilia
beyond 3m (6m in practice)
PE
how long should pt continue long term anticoagulation if pt has active cancer
6m (then review)
PE
mnx for a massive PE with haemodynamic compromise
thrombolysis: streptokinase, alteplase, tenecteplase
PE
which 2 ways can thrombolysis be performed
- IV using a peripheral cannula
- directly into pulmonary arteries using a central catheter (catheter-directed thrombolysis)
Pulmonary Hypertension
causes: group 1
Primary pulmonary hypertension or connective tissue disease
Pulmonary Hypertension
causes: group 2
L heart failure due to MI or systemic HTN
Pulmonary Hypertension
causes: group 3
chronic lung disease such as COPD
Pulmonary Hypertension
causes: group 4
pulmonary vascular disease such as PE
Pulmonary Hypertension
causes: group 5
miscellaneous causes: sarcoidosis, glycogen storage disease + haem disorders
Pulmonary Hypertension
main presenting sx
SOB
Pulmonary Hypertension
signs and sx
- SOB
- syncope
- tachycardia
- raised JVP
- hepatomegaly
- peripheral oedema
Pulmonary Hypertension
ECG changes (3)
- R ventricular hypertrophy
- R axis deviation
- RBBB
Pulmonary Hypertension
how does R ventricular hypertrophy present on an ECG
larger R waves on the R sided chest leads (V1-3)
S waves on the L sided chest leads (V4-6)
Pulmonary Hypertension
CXR changes (2)
- dilated pulmonary arteries
- R ventricular hypertrophy
Pulmonary Hypertension
what blood test result may indicate R ventricular failure
a raised NT-proBNP
Pulmonary Hypertension
what inx can be used to estimate pulmonary artery pressure
Echo
Pulmonary Hypertension
what can primary pulmonary hypertension be treated with? (3)
- IV prostanoids e.g. epoprostenol
- Endothelin receptor antagonists (e.g macitentan)
- Phosphodiesterase-5 inhibitors (e.g. sildenafil)
Pulmonary Hypertension
mnx of secondary pulmonary hypertension
treat underlying cause such as PE or SLE
PE
ECG changes
- S1Q3T3
- RBBB + right axis deviation
- sinus tachycardia
PE
what is S1Q3T3
- large S wave in lead I
- large Q wave in lead III
- inverted T wave in lead III
ipsilateral Horner’s syndrome + thoracic outlet syndrome (shoulder pain radiating down arm, motor weakness of the intrinsic hand muscles)
cause?
Pancoast tumour
invasive apical lung cancer invading the sympathetic plexus and brachial plexus.
can also cause a hoarse voice and bovine cough if it is affecting the laryngeal nerve.
smoke inhalation
mnx for all pts
endotracheal tube
+ analgesia + anxiety trx: morphine, propofol
smoke inhalation
mnx for CO poisoning
high-flow supplemental oxygen
what does a CO-Hb level >15% indicate
carboxyhaemoglobin
CO poisoning
COVID medication mnx
- dexamethasone
- IL-6 inhibitor: tocilizumab, sarilumab
- Remdesivir
Acute Asthma
presentation
- progressively worsening SOB
- use of accessory muscles
- tachycardia
- symmetrical expiratory wheeze on auscultation
- chest can sound ‘light’ on auscultation with reduced air entry
Acute Asthma
moderate PEFR
50-75% predicted
Acute Asthma
severe signs?
- PEFR 33-50% predicted
- RR>25
- HR >110
- unable to complete sentences
Acute Asthma
life-threatening signs
- PEFR <33%
- Sats <92%
- becoming tired
- no wheeze
- haemodynamic instability
Acute Asthma
what is silent chest
in life threatening asthma
airways are so tight that there is no air entry at all
Acute Asthma
mnx for moderate acute asthma
- neb salbutamol 5mg repeat as often as required
- neb ipratropium bromide
- PO prednisolone or IV hydrocortisone (continued for 5d)
Acute Asthma
mnx for severe acute asthma
- O2 if required to maintain sats 94-98%
- aminophylline infusion
- consider IV salbutamol
Acute Asthma
mnx for life-threatening acute asthma
- IV magnesium sulphate infusion
- admission to ICU/HDU
- intubation in worst cases
Acute Asthma
initially what will ABG show and why
respiratory alkalosis as tachypnoea causes a drop in CO2
Acute Asthma
which ABG results is a very bad sign
resp acidosis due to high CO2
Acute Asthma
when an ABG has normal pCO2 or hypoxia, what does it mean
a concerning sign as it means they are tiring and indicates life threatening asthma