Question 29.2

A 64-year-old male has been an in-patient in your ICU for one week following a subarachnoid haemorrhage. The following data were obtained from a CSF sample taken from the external ventricular drain:


Patient Value          

Adult Normal Range


3.8 mmol/L

2.2 – 3.9


0.46 G/L

0.15 – 0.50

White Cell Count

20 x 106/L*

< 5

Red Cell Count

10,000 x 106/L*

< 5

a)    Interpret these results in the context of the brief history given.    (20% marks)

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College answer

Not available.


This question is identical to Question 3.2 from the second paper of 2013.

This is a fairly straightforward data interpretation question. 10,000 / 20 = 500; which is the perfect ratio. This CSF is not infected, it just has blood in it.

Of course, in order to make a more accurate analysis, it would be good to also know the serum WCC, so that one may calculate the proper ratio.

A more detailed discussion of CSF analysis is available elsewhere.