No abstract

Introduction: Although transcranial Doppler (TCD) evaluation for vasospasm remains an important study in aneurysmal subarachnoid hemorrhage (aSAH) management, its precise role in predicting delayed cerebral ischemia (DCI) remains unclear. Hypothesis: We evaluated optimal measures for evaluating TCD velocities and hypothesized that TCD velocity change would be the best predictor for DCI in patients with aSAH. Methods: Patients with aSAH over a two-year period were retrospectively analyzed. Baseline characteristics, outcomes, and TCD velocities in bilateral middle cerebral arteries (MCA) for hospital days 2 to14 were recorded. TCD variables, including absolute velocity and change in velocity, were obtained by creating a smoothing curve. A variable representing change in TCD velocity was then created through a linear regression model that confirmed greatest change in velocity associated with DCI occurred at days 2-7. Multivariate logistic regression analysis using DCI as outcome was then completed. Results: 95 patients with aSAH were evaluated. Increased TCD velocity at days 2-7 proved to be a better predictor for DCI than absolute velocity with an optimal cutoff of 8.9 cm/sec/day ( p = 0.019) and AUC 0.651. Multivariate logistic analysis using DCI as the outcome showed that poor admission Hunt-Hess scores (OR 5.02, 95%CI 1.22-22.67, p = 0.028) and increase in TCD velocity during days 2-7 (OR 5.32, 95%CI 1.41-23.33, p = 0.018) were independently associated with DCI. Conclusions: We found that relative increases in TCD velocities in the MCAs during the first 7 days (threshold increase of 8.9 cm/sec/day or 53.4 cm/sec from days 2-7) after aSAH were independently associated with DCI. Our findings suggest that vasospasm should be confirmed and treated aggressively when detected via increased TCD velocities during the first seven days in order to minimize DCI. This association requires independent confirmation.