Death by Neurological Criteria (DNC) in ICU: Usefulness of Transcranial Doppler (TCD)

Transcranial Doppler (TCD/TCCS) is very useful to establish the diagnosis of cerebral circulatory arrest that accompanies brain death. A complete TCD/TCCS study to establish the diagnosis of cerebral circulatory arrest requires a complete study of the anterior and posterior cerebral circulation. There are three sonographic patterns compatible with the diagnosis of cerebral circulatory arrest: diastole-systole separation, reverberant flow, and isolated systolic spikes. The absence of blood flow velocities’ insonation in patients who had previously been insonated is considered by some to be compatible with the diagnosis of cerebral circulatory arrest. Transcranial Doppler has its main limitation of use in patients in whom there are closed-vault defects.