April 23, 2014

Explain it: CT and Subarachnoid Hemorrhage

Sensitivity of computed tomography performed within six hours of onset of headache for diagnosis of subarachnoid haemorrhageĀ 

While the paper has been out for a while and has even been covered on ERcast, it still causes quite a bit of confusion. This 10 minute breakdown (which is part of a monthly lecture series I give to my group) may help.


The views expressed herein are those of the author and do not represent those of Providence Health System.

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  1. Tim LaBelle says:

    Jerry Hoffman condemned the conclusions of this study for a variety of reasons (that I am sure you are aware of). I asked Mel about getting a panel discussion going with you,Scott,Stewart ,Mel,Jerry,David Newman etc. for EMRAP . I am not convinced
    Tim LaBelle

    • Rob Orman says:


      I have not heard Jerry’s take on this paper and would love to hear what he has to say.

      • Tim LaBelle says:

        If you go to Dave Newman’s site SMART EM his March podcast discusses this in detail including Jerry’s concerns. It is well worth the listen .

        • Rob Orman says:

          Tim- I listened to the summary on SmartEM and don’t have a problem with any of Jerry’s criticism. It’s all true. However, this paper does give useful information in predicting short term outcome in the patient group with negative CT done within 6 hours of headache. The fact that LP was not done is irrelevant to that. By my take, this paper did not actually rule out SAH in all of these patients, since the current gold standard of CT and LP was not used. What it did say was that if the CT is negative within 6 hours of symptom onset, the patient has an extremely low likelihood of dying from SAH in the near future.

  2. Doug Larsen says:


    Related to this topic, if you have a patient with a really great story for a SAH but they are outside the 6 hour window set up by this study, does anyone consider getting CTA with the initial CT. If negative CT brain and CTA I think you are in the clear. But if your CT is negative and you have an aneurysm with a really good story it’s time to talk with your neurosurgeon.


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