Hyperemia in head injury: can transcranial doppler help to personalize therapies for intracranial hypertension?

Abstract

IntroductionAn increase in cerebral blood flow is frequent after traumatic brain injury (TBI) and can lead to brain swelling and refractory intracranial hypertension. We hypothesized that Transcranial EcoDoppler (TCD) monitoring could be useful to detect the cause of intracranial hypertension in these patients. Our main objective was to investigate if the increase of velocity in the middle cerebral artery (MCA) on TCD could be associated with intracranial hypertension.MethodsWe retrospectively studied TBI patients consecutively monitored with TCD. Hyperemia was defined as MCA mean velocity higher than 80 cm/s. Intracranial hypertension was considered when hyperosmolar therapy, hyperventilation, or deep sedation was used.ResultsWe found hyperemia in 40 patients out of 118 (33.9%). On average, it started at day 2.1 ± 0.9 from admission and significantly increased (MCA velocity at day 1: 74 ± 25 cm/s vs. 109 ± 36 cm/s at day 4; p < 0.001). Intracranial hypertension was significantly associated with hyperemia, occurring in 92.5% of hyperemic and 51.3% of non-hyperemic patients (p < 0.001). Moreover, we found that hyperemia preceded severe intracranial hypertension (p < 0.0001). In a logistic regression model, hyperemia was the only variable significantly correlated with intracranial hypertension (OR 10.64; p < 0.001).DiscussionHyperemia was frequent in our population of TBI patients and preceded intracranial hypertension. TCD monitoring, if performed on a daily regular basis, can be a useful method to detect this phenomenon and to guide the therapy. It could be a tool for a cause-oriented therapy of intracranial hypertension.

Robotic-Assisted Transcranial Doppler Monitoring in Acute Neurovascular Care: a Feasibility and Safety Study

“…In fact, several studies highlight the key role of TCD in the evaluation of cerebral autoregulation and for the early detection of intracranial hypertension. 4,[14][15][16] Although the skull provided an ideal platform for mounting monitoring TCD probes, cerebral monitoring with TCD has been limited so far, because it still requires a trained sonographer for the entire duration of the examination, making it not feasible in many institutions. 17 Robotic assisted TCD (ra-TCD) was developed to overcome these constraints, using arti cial intelligence to automatically detect intracranial blood ow signals and continue its monitoring without the constant need of an operator keeping the probe aimed right on its target.…”