Neuroprotective Therapy and Therapeutic Target in Emergency Department

In previous reports, many predictors of early deterioration after ischemic stroke have been proposed and studied, yet the results remain controversial. For example, several studies have been performed to ascertain whether cerebral or systemic causes are the major determinants of stroke deterioration. The findings, however, have been inconsistent. Measures of overall status and stroke severity (low initial Canadian Stroke Severity score, low initial National Institutes of Health Stroke Scale score, early CT findings of stroke severity, and changes in cerebral blood flow affecting the ischemic penumbra as measured by positron emission tomography and single photon emission computed tomography imaging have been shown to predict early deterioration. Laboratory tests for coagulation markers (fibrinogen, D-dimers), inflammatory markers (increased interleukin-6, decreased interleukin-10), serum glucose at admission, hematocrit and physiological parameters, such as blood pressure (both elevated and decreased), and body temperature have been identified as predictors of early deterioration. In addition, patient medical history (diabetes mellitus, atherosclerosis, chronic heart disease) has also been associated with early stroke deterioration. These differing findings may be due to variations in study design, patient populations, selection and exclusion criteria, and the criteria used for defining early deterioration.

A further complication in trying to determine predictors of early deterioration after stroke is that different stroke subtypes may manifest differently in terms of clinical changes before deterioration. In most of the aforementioned studies, no attempt was made to differentiate among stroke subtypes. While others have shown that some proposed markers are statistically significant only for certain stroke subtypes. A predictor of early deterioration that is equally applicable to all stroke subtypes is needed.

The investigators studied laboratory measurements and previously identified risk factors to identify factors predictors of early deterioration following stroke. A prospective observational study of 196 patients with first-time acute ischemic stroke was performed. Following multivariate analysis, only a Bun/Cr >15 was independent predictor of SIE. These patients were 3.41-fold more likely to have SIE (P=0.008). The elevated Bun/Cr ratio indicates relative dehydration of the patients.

Monitoring of hydration status would also appear to be critical in these patients. Being able to accurately identify patients at risk for early deterioration following stroke will allow for the design of clinical trials of stroke intervention targeting patients with SIE. The investigators need further tests to confirm if the maintenance of proper hydration improve outcome in patients with a Bun/Cr ratio higher than 15.