Transcranial Doppler Shortens the Time Between Clinical Brain Death and Angiographic Confirmation

Abstract

Brain death diagnosis relies on clinical signs, but confirmatory tests are legally mandatory in some countries. In France, transcranial Doppler (TCD) is not recognized as a legal test to confirm brain death. Nevertheless, experts recommend its use to determine the need for a legal confirmatory test. The aim of this study was to test the hypothesis that TCD shortens the time between clinical brain death and computed tomography angiography (CTA) confirmation. We conducted a prospective randomized controlled study to evaluate the benefit of a TCD-directed strategy before performing the CTA to confirm brain death. Once the clinical diagnosis of brain death was established, subjects were randomized in a conventional group (CTA 6 hr later as recommended in France) or a TCD group (TCD examination every 2 hr until intracranial brain death flow patterns were found). Forty-four subjects were needed to show a difference of 2 hr between the two strategies. TCD strategy resulted in a shorter time between clinical diagnosis of brain death and CTA confirmation compared with conventional strategy (2.0 [1.3-2.6] vs. 7.2 [6.3-9.5] hr, P<0.0001). The number of brain CTA performed to confirm the diagnosis of brain death was not different between groups. Our results suggest that TCD-directed strategy allows reducing the time between clinical diagnosis of brain death and CTA confirmation.