Introduction to Respiratory Flashcards
Presenting complaints of respiratory disease.
Dyspnoea
Chest pain
Wheeze
Cough
Sputum
Haemoptysis
History of dyspnoea
MRC score
Exercise tolerance?
Triggers?
Relieving factors?
Diurnal variation?
Orthopnoea?
PND (paroxysmal…)
History of chest pain
Site?
Severity?
Radiation?
Triggers?
Relieving factors?
Associated symptoms
History of wheeze
Triggers?
Relieving factors?
Diurnal variation?
Associated cough?
History of cough
Dry/Prod?
Triggers
Relieving factors
Diurnal variation
Association with eating or dyspepsia?
Positional?
Nasal secretions?
Fever?
History of sputum
How much over 24h?
Colour?
Consistency?
History of haemoptysis
Quantity and frequency
Fever?
Night sweats?
Appetite?
Weight loss?
What is the MRC dyspnoea score?
1 - Not troubled by breathlessness except on strenous exercise
2 - Short of breath when hurrying or walking up a slight incline
3 - Walks slower than contemporaries on level ground because of breathlessness, or has to stop for breath when walking at own pace
4 - Stops for breath after walking about 100m or after a few minutes on level ground
5 - Too breathless to leave the house, or breathless when dressing or undressing
What FH to specifically ask for in respiratory disease.
Respiratory disease
Cardiac disease
Cancer
Thrombophilia
CF
Social history of respiratory disease.
Smoking
Occupational history
Pets
Recent foreign travel
Immobility
Activities of daily living
Alcohol
Performance status (Cancer)
What is WHO performance status?
0 - Fully active without restriction
1 - Restricted in physically strenous activity but ambulatory and able to carry out light work-
2 - Ambulatory and capable of all self-care, but unable to carry out any work activities. Up and about more than 50% of waking hours.
3 - Capable of only limited self-care, confined to bed or chair more than 50% of waking hours.
4 - Completely disabled. Cannot self-care. Totally confined to bed or chair.
5 - Dead
Approach to a CXR.
Name, age and date of CXR
Type of CXR (PA or AP, erect or mobile)
Quality (Rotation, penetration, adequare inspiration)
ABC (Airways/lungs, Bones, Cardiac)
Trachea, apices, behind the heart, beneath diaphragm, soft tissues.
Cardiothoracic ratio
Give four common causes of a low PaO2.
Hypoventilation
Diffusion impairment
Shunt
V/Q mismatch
What is the A-a gradient?
PAO2 = PIO2 - PaCO2/0.8
PAO2 = Alveolar partial pressure of oxygen
PIO2 = Room air (approx. 20 kPa)
PACO2 = Virtually the same as arterial partial pressure of carbon dioxide (PaCO2)
It shows the gradient between the alveolar partial pressure of oxygen and the arterial partial pressure of oxygen.
It is used to assess the severity of respiratory failure, particularly in ARDS.
What should the A-a gradient be in young healthy vs older healthy?
What implies lung pathology?
In young healthy = < 2kPa
In older = < 4kPa
Lung pathology = > 4kPa
A 26 year old femlare nurse thought to be hyperventilating.
pH = 7.56
pCO2 = 2.7
pO2 = 11.5
B.E. = -2
HCO3 = 23
What is the A-a gradient?
PAO2 = PIO2 - PaCO2/0.8
20 - 2.7/0.8
20 - 3.4 = 16.6 kPa
16.6 - 11.5 =5.1 kPa
This shows that there is a problem with the lungs, not only hyperventilation.
Give common clinical features of respiratory disease.
Runny, blocked nose and sneezing
Cough
Sputum
Haemoptysis
Dyspnoea
Wheezing
Chest pain
How much mucus is produced daily in a healthy, non smoking individual?
100 ml
100 ml is produced, but not usually coughed up. Where does it go?
It is usually swallowed
Most common cause of excess mucous produciton.
Cigarette smoking
Features of mucoid sputum.
Clear and white
Can contain black specks due to carbon inhalation.
Why might sputum be green or yellow?
Presence of cellular material like bronchial epithelial cells, neutrophils or eosinophil granulocytes.
Why might yellow sputum not indicate infection?
Granulocytes in the sputum from asthma can give the sputum a yellowish colour.
What is production of large quantities of yellow or green sputum indicative of?
Bronchiectasis
Some haemoptysis can be seen in bronchiectasis as well.
Most common cause of mild haemoptysis.
Acute infection, particularly in exacerbation of COPD
(This should not be assumed without investigation)
Other common causes of mild haemoptysis
Pulmonary infarction 2ndary to PE
Bronchial carcinoma
TB
Cause of pink frothy sputum
Pulmonary oedema
Common causes of massive haemoptysis (>200 ml of blood in 24h)
Bronchiectasis
TB
Also later stages of lung cancer.
Other causes of haemoptysis.
Pulmonary emboli
CHF
Pulmonary fibrosis
Vasculitis (Anti-GBM, polyangiitis,)
Severe pulmonary hypertension
Arteriovenous malformation
Chest trauma
Endometriosis
Anticoagulation
Drugs
What is orthopnoea clasically linked to?
Heart failure
Weight of the abdominal contents pushing the diaphragm up into the thorax on lying down also contributes
What is wheezing?
High pitched noise on expiration
Can be seen in asthma, vocal cord dysfunction, bronchiolitis
COPD
Most common presentation of pleuritic chest pain.
Localised sharp pain
Worsened by deep breathing and coughing.
Patient can usually localise it.
What does localised anterior chest pain with tenderness of a costochondral junction usually indicate?
Costochondritis
What does should tip pain suggest?
Irritation of the diaphragmatic pleura.
What does central chest pain radiating to the neck and arms suggest?
Cardiac
What is retrosternal soreness associated with?
Tracheitis
Signs to look for in the hands of respiratory disease.
Clubbing
Pallor
Warm, well-perfused hands (CO2 retention)
Cyanosis
Flap
Tremor
Tobacco staining
Bruising and/or thin skin
Pulse rate and character
What is coarse tremor or flap of the outstretched hand usually indicative of?
Also called asterixis
CO2 intoxication
Hepatic failure
Hepatic encephalopathy
Opiate overdose
Wilson’s disease
Give causes of finger clubbing.
Bronchial carcinoma
Bronchiectasis, lung abscess, empyema.
Mesothelioma
Cyanotic heart disease
Subacute infective endocarditis
Atrial myxoma
Congenital (w/o disease)
Cirrhosis
IBD
Thyroid acropachy
When might a tape measure be used to measure precise or serial measurements of chest expansion?
To examine ankylosing spondylitis
When are wheezes monophonic?
When there is a single large airway obstruction
When is a wheeze polyphonic?
Whwn there is narrowing of many small airways.
What are early inspiratory crackles associated with?
Diffuse airflow limitation
What are late inspiratory crackles usually associated with?
Pulmonary oedema
Lung fibrosis
Bronchiectasis
When is pleural rub heard?
Lung infections
Consolidation
Causes of lung collapse
Enlarged trachobronchial lymph nodes due to malignant disease or tuberculosis
Inhaled foreign bodies in children
Bronchial casts or plugs
Retained secretions post-op
Causes of round shadows >3cm in lung.
Carcinoma
Metastatic tumours
Lung abscess
Encysted interlobar effusion
Hydatid cysts
AV malformations
Aspergilloma
Rheumatoid nodules
Tuberculoma
Bronchial carcinoid
Cylindroma
Chondroma
Lipoma
CXR presentation of localised fibrosis.
Streaky shadowing accompanying loss of lung volume causing mediastinal structures to move to the same side.
CXR presentation of generalised fibrosis.
Honeycomb appearance, seen as diffuse shadows containing multiple circular translucencies a few millimetres in diameter
Most common cause of round shadows.
Lung cancer
Causes of miliary mottling
TB
Pneumoconiosis
Sarcoidosis
Idiopathic pulmonary fibrosis
Pulmonary oedema
Pulmonary microlithiasis
What is HRCT (High resolution CT) useful for?
Evaluation of diffuse disease of the lung parenchyma such as sarcoidosis, hypersensitivity pnuemonitis, occupational lung disease and any other form of interstitial pulmonary fibrosis.
Diagnosis of bronchiectasis
Distinction of emphysema from diffuse parenchymal lung disease or pulmonary vascualr disease.
Suspected opportunistic lung infection
Diagnosis of lymphangitis carcinomatosa
When is multi-slice CT particularly useful in?
Detection of PE
When is CT pulmonary angiography particularly useful?
In detecting PE
What might be used to assess lung cancer staging?
HRCT
MRI
PET-CT
When might ultrasound be used?
To assess pleural effusion
When else is ultrasound used?
In other accompanying procedures as well.
In pleural aspiration and intercostal chest drain placement.
Ultrasound-guided biopsy.
Bronchoscopy (endobronchial ultrasound (EBUS))
Give examples of different respiratory function tests.
Spirometry
PEFR
Flow-volume loops
Lung volumes
Transfer factor
Measurement of blood gases
Exhaled nitric oxide
Cardiopulmonary testing
Nocturnal polygraphy
What is spirometry useful for?
Helps to differentiate between obstructive and restrictive patterns of respiratory compromise.
Advantage of PEFR.
Extremely simple and cheap test.
Subjects take a full inspiration to TLC and then blow out forcefully into the peak flow meter.
The best of three results is recorded.
What is PEFR mainly used for?
Aid in diagnosis of asthma.
Monitor exacerbations of asthma and response to treatment.
Explain the what the different parts of a flow-volume loop means.
At the start of expiration from TLC, maximum resistance is from the large airways. This affects the flow rate for the first 25% of the curve.
As the air is exhaled, the lung volume reduces and the flow rate becomes dependent on the resistance of the smaller airways.
Explain at what lung volumes the flow-volume loop will be affected in COPD.
COPD affects the smaller airways.
At 50% and 25% of total lung volume the flow rate will be reduced.
What can tidal volume and vital capacity be measured by?
Spirometer
What techniques can be used for measurement of TLC and RV?
Inhaling air containing a known concentration of helium and then measuring the dilution in the exhaled air.
RV can then be calculated by subtracting the VC from the TLC.
When is the inhalation of helium technique inaccurate in measuring TLC?
When there are large cystic spaces because helium cannot diffuse into them.
What is used to measure TLC if there are large cystic spaces?
Body plethysmograph
Explain transfer factor.
Normal lungs = transfer factor accurately reflects how efficiently oxygen diffuses from alveolar air into blood. Depends on the thickness of alveolar-capillary membrane.
In lung disease the diffusing capacity is also affected by ventilation-perfusion relationship.
CO is used as it has a similar diffusion rate to O2. Low conc. of CO is inhaled and rate of absorption is calculated.
To control for lung volume differences the uptake of CO is expressed relative to lung volume.
When is gas transfer reduced?
Emphysema
Fibrosis
Heart failure
Anaemia
What is transfer factor useful in detecting and monitoring?
Idiopathic pulmonary fibrosis
Sarcoidosis
Asbestosis
When is the transfer factor raised?
Pulmonary haemorrhage
What is exhaled nitric oxide measuring useful in?
NO is produced by bronchial epithelium and increases in asthma and airway inflammation.
Used to guide therapy in asthma.
How is cardiopulmonary exercise testing done?
On a treadmill or a cycle ergometer.
Oxygen consumption, CO2 production and ventilation is calculated.
What is cardiopulmonary exercise testing used for?
Assessment of cardiopulmonary reserve.
Provides information about cardiorespiratory and metabolic muscle function.
What is nocturnal polygraphy used for?
Investigation of sleep-disordered breathing.
What is haemoglobin tested for?
Detect anaemia or polycythaemia
What is packed vell volume tested for?
Secondary polycythaemia due to chronic hypoxia
What do disturbed routine biochemistry suggest?
Lung cancer or infection
Why are D-dimers assessed?
Negative D-dimers makes PE very unlikely.
Other blood investigations that might be done.
alpha-antitrypsin levels.
Aspergillus antibodies
Vira and mycoplasma serology
Autoantibody profile
IgE measurements
When are gram stain and sputum cultures useful?
In pneumonia
TB (acid-fast bacilli)
Bronchiectasis
Give examples of diagnostic pleural aspiration.
Determine aetiology of a pleural effusion.
Why would you do a therapeutic pleural aspiration?
Relieve extreme breathlessness in large pleural effusion.
Explain how pleural aspiration is performed.
Under ultrasound guidance.
Needle is inserted under local anaesthesia at the top of area identified on US.
Fluid is withdrawn and blood is noted.
Samples are sent for cytology and biochemical analysis.
Protein, LDH, bacteria, Ziehl-Neelsen staining might be done.
When might pleural biopsy be done?
Unilateral exudative pleural effusion or suspicious pleural thickening.
CT or ultrasound guided.
When are intercostal drains performed?
Pneumothorax
Large pleural effusion
Empyema
What will fibreoptic bronchoscopy show?
Endobronchial tree down to the subsegmental level
What is a fibreoptic bronchoscopy always performed under?
Local anaesthesia and sedation
When might fibreoptic bronchoscopy be done?
Visualisation and biopsy of an endobronchial lesion.
Collapse lung or lobe (look for cause)
Microbiological sampling
Diagnosis of diffuse inflammatory and infective lung processes
Performance of EBUS
Haemoptysis
What is mediastinoscopy used for?
Performed under general anaesthesia.
Used for diagnosis of mediastinal masses
Staging of nodal disease in carcinoma of bronchus.
Not done as much since EBUS
Explain skin-prick tests.
Allergen solutions are placed on the skin and epidermis is broken.
If the patient is sensitive to the allergen a weal will develop.
The diameter is measured after 10 minutes, > 3 mm is regarded as positive, provided that the control is negative.
Discontinue anti-histamine 48 hours in advance.
Explain bronchial provocation test.
May be useful in diagnosis of asthma (definitive diagnosis)
Airway hyper-responsiveness is a characteristic feature of asthma.
Patient inhales gradually increasing concentrations of histamine or methacholine.
Induces transient airflow limitation in susceptible individuals.
Severity of AHR can be graded according to the provocation dose or concentration provided.
Patients with clinical symptoms of asthma respond to very low doses of methacholine.
Explain intercostal drainage procedure.
Identify site for aspiration (usually done with ultrasound)
Sterilise
Anaesthetize skin, muscle and pleura with 2% lidocaine
Small incision and insert an 8-12 french gauge drain using the Seldinger technique.
Attach to a three-way tap and 50 ml syringe and aspirate up to 1000 ml.
If the drain is to stay in, secure it to skin with suture and sterile dressing.
Attach to underwater seal. Clamp drain and release periodically.
Perform a CXR to check position of the drain.
