Respiratory

Question 1

In the ED setting, what evidence is there re salbutamol delivery via MDI vs nebuliser?

Answer 1

Salbutamol delivered via MDI and spacer is as effective as nebulised salbutamol and can result in shorter stays in the emergency department and better peak flow results.

Question 2

What is the modified wells criteria?

Answer 2

A scoring system to group patients into low, medium and high risk for PE.

3 points each for: clinical symptoms of DVT (leg swelling, pain with palpation), other diagnoses less likely than PE

1.5 each for: HR greater than 100, immobilisation (3 days) or surgery in the previous 4 weeks, previous DVT/PE

1 each for: haemoptysis and malignancy

Score: more than 6 = high, 2 to 6 = moderate, less than 2 = low

Question 3

When is a D-dimer useful?

Answer 3

In low risk patients, a negative D-dimer predicts the absence of PE with approx. 99% certainty, using an ELISA assay

BUT poor specificity

In other words, a positive D-dimer is not synonymous with PE, but a negative D-dimer is, with a good degree of certainty, an indication of absence of a PE. The typical cut off is 500 ug/

Question 4

What can cause a false positive D-dimer result? (5)

Answer 4

1. myocardial infarction
2. sepsis
3. trauma
4. renal disease
5. pregnancy