Clinical Pathways
Clinical Pathways
Negative for SAH or Limited Study
Negative for SAH or Limited Study

Negative for SAH or Limited Study

View The Full Pathway

Decision

What is the pretest probability based on history?

See background section below.

Background

Table 5 summarizes the key pieces of information that emergency clinicians should obtain during careful history taking to aid in identifying sSAH. It is important to emphasize that in patients with normal physical examinations, there are no significant features of the headache that allow reliable distinction between SAH and headaches of benign etiology.57,74^{57,74} Emergency clinicians cannot rely upon how well the patient looks to estimate the pretest probability of sSAH.59−62^{59-62} For example, a retrospective study of more than 200 patients who underwent aneurysmal clipping found that 8% of patients did not have a headache at the onset of sSAH, but instead presented with sudden onset of general malaise or isolated neck or back complaints.77^{77} Table 6 , describes distracting clinical scenarios in diagnosing sSAH.

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References

Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, random-ized, and blinded trial should carry more weight than a case report.

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