To present the practical aspects of transcranial Doppler (TCD) and provide evidence supporting its use for the management of traumatic brain injury (TBI) patients.TCD measures systolic, mean, and diastolic cerebral blood flow (CBF) velocities and calculates the pulsatility index from basal intracranial arteries. These variables reflect the brain circulation, provided there is control of potential confounding factors. TCD can be useful in patients with severe TBI to detect low CBF, for example, during intracranial hypertension, and to assess cerebral autoregulation. In the emergency room, TCD might complement brain computed tomography (CT) scan and clinical examination to screen patients at risk for further neurological deterioration after mild-to-moderate TBI.The diagnostic value of TCD should be incorporated into other findings from multimodal brain monitoring and CT scan to optimize the bedside management of patients with TBI and help guide the choice of appropriate therapies.
