Background: One of the goals in treating subarachnoid hemorrhage patients is to prevent or minimize vasospasm-induced ischemia. Intracerebral microdialysis is a rapidly developing tool to monitor physiological and pathophysiological changes in chemical processes associated with ischemia.
Objective: To determine the diagnostic accuracy of microdialysis in detecting ischemia or ischemic events in patients with subarachnoid hemorrhage.
Methods: A systematic review of clinical studies regarding microdialysis as a monitoring method in patients in the acute stage of subarachnoid hemorrhage was conducted by performing a MEDLINE search using the terms "subarachnoid hemorrhage", "brain ischemia", "intracranial aneurysm", "cerebrovascular accident" and "stroke". These were combined with a search on "microdialysis". The methodological quality of the studies was assessed independently by two reviewers. For each study the grades of recommendation were determined.
Results: The search yielded 73 publications of which 13 studies were analysed. The methodological quality of the studies was low,with only 3 studies fulfilling more than 50% of the criteria. Consequently the level of evidence was low. Of the internal validity criteria the characteristics of study populations were similar in most of the studies. The technical assessment varied considerably. A quantitative analysis (meta-analysis) could not be performed because of lack of sufficient data. A qualitative analysis yielded a positive impression with regard to the diagnostic accuracy of microdialysis in detecting ischemic events.
Conclusion: There is a positive tendency to use microdialysis as a diagnostic tool for monitoring of ischemic events in subarachnoid hemorrhage patients. However, there is insufficient evidence for the routine use of microdialysis.