Respiratory Flashcards
What is the MRC score?
Score used for breathlessness, graded 1-5:
1-not troubled by breathlessness unless strenuous exercise
2-SOB when hurrying or walking up slight hill
3-walks slower than normal due to breathlessness of has to stop to catch breath
4-stops for breath after walking 100m
5-SOB when dressing, struggles to leave house
What is bullous emphysema?
A condition where damaged alveoli distend to form large air spaces, it occurs in otherwise healthy adults and usually gets noticed when an abnormal air space ruptures, leaking air into the pleural space and causing a pneumothorax (it is not the same as pulmonary emphysema which is a complication of COPD).
What investigations would you do for a suspected pleural effusion?
CXR
Fluid aspiration
What is the difference between transudative and exudative pleural effusion?
Transudative - occurs due to increased hydrostatic pressure or decreased plasma osmotic pressure e.g. CHF, cirrhosis, nephrotic syndrome, PE, hypoalbuminaemia.
Exudative - occurs due to inflammation and increased capillary permeability e.g. Pneumonia, cancer, TB, viral infection, PE, autoimmune.
Name some causes of COPD.
Smoking - active or passive
Pollution
Alpha-1 antitrypsin deficiency
What are the most common causes of a pleural effusion?
Infection
Malignancy
What is the CURB-65 score used for and what do all the components stand for?
Used to estimate risk and guide management in community acquired pneumonia.
C-confusion
U-urea >7.0
R-RR>30/min
B-BP<90 systolic of <60 diastolic
65 - aged 65 years +
The higher the score, the worse the pneumonia
What is aspiration pneumonia?
Occurs when food, saliva, liquids or vomit is breathed into the lungs or large airways instead of being swallowed. If these things carry bacteria then this can cause pneumonia.
Name some causes of non-resolving pneumonia.
CHAOS
Complication - emphysema, lung access
Host - immunocompromised
Antibiotic - inadequate dose or poor oral absorption
Organism - resistant or unexpected
Second diagnosis - PE, cancer, organising pneumonia
What is empyema?
Pus in the pleural space, needs to be drained and cannot be treated with ABX as the pleural space has no blood supply
What is ‘honeycombing’ on a chest x-ray?
The radiological appearance seen with widespread fibrosis - appears as lots of white dots looking a bit like a honeycomb. These changes are seen in many end-stage interstitial lung diseases.
What are pleural plaques?
Areas of benign thickening of the lining of the lungs after prolonged asbestos exposure.
What is asbestosis?
Long term inflammation and scarring of the lungs due to exposure to and breathing in asbestos fibres.
When would you see an air bronchogram on a CXR?
Present in pneumonia - the airway is filled with air and surrounded by inflammatory exudates, therefore the airway shows up as dark.
What is the A-a gradient? What should a normal value be?
Alveolar arterial gradient, can be useful to work out if there is a respiratory problem as it is a measure of good gas exchange is. Should be <2kPa in healthy adults and <4kPa in older people. Anything >4kPa implies lung pathology
What is the equation to work out alveolar pO2?
PAO2 = PIO2 - PACO2/0.8
Where PIO2 is oxygen in room air (20kPa) and PACO2 is basically the same as arterial PaCO2.
What is the criteria for doing an ABG in an acute asthma patient?
If sats <92% on presentation.
What is the difference between CPAP and BIPAP?
CPAP is not a form of ventilatory support and provides constant positive pressure during inspiration and expiration, can be used for people with obstructive sleep apnoea.
BIPAP is a form of NIV (non-invasive ventilation) and has different positive pressures for inspiration and expiration, a form of ventilatory support.
What is chronic bronchitis?
Cough and sputum production on most days for 3 months of 2 successive years, caused by mucous hypersecretion.
What is emphysema?
Enlarged air spaces distal to the terminal bronchioles caused by destruction of alveolar walls.