# Very early tilt-table verticalization unmasks impaired cerebral autoregulation within 24 h after endovascular thrombectomy: a transcranial Doppler study

## TL;DR

Early verticalization after stroke treatment reveals impaired blood flow control in the brain, suggesting risks for early mobilization.

## Contribution

The study identifies compromised cerebral autoregulation in stroke patients within 24 hours post-thrombectomy using tilt-table testing.

## Key findings

- CBFV decreased more in stroke patients at 70° tilt, indicating impaired cerebral pressure-flow regulation.
- Diastolic blood pressure failed to rise in stroke patients during tilt, showing systemic vascular resistance issues.
- Real-time CBFV monitoring is proposed as a potential biomarker for autoregulatory integrity in stroke rehabilitation.

## Abstract

Impaired cerebral autoregulation in the acute phase after ischemic stroke may compromise cerebral perfusion during very early mobilization, posing a risk for secondary injury.

This observational cross-sectional study investigated the mechanistic response of cerebral and systemic hemodynamics during progressive tilt-table verticalization in 25 patients within 24 h post-thrombectomy and 31 healthy age-matched controls. Middle cerebral artery blood flow velocity (CBFV) was continuously recorded via transcranial Doppler across six full-body tilt positions (−5° to 70°), alongside blood pressure, heart rate, and oxygen saturation.

CBFV declined progressively with increasing tilt in both groups (p < 0.001), but the reduction at 70° was significantly greater in stroke patients (p = 0.007), indicating compromised cerebral pressure-flow regulation. Diastolic blood pressure, linked to systemic vascular resistance, increased with tilt in controls but failed to rise in stroke patients, remaining significantly lower throughout.

Our results suggest impairments in cerebral and systemic vascular control mechanisms in acute stroke patients post thrombectomy. These results provide further insight into the physiological constraints limiting early verticalization and underscore the value of real-time CBFV monitoring as a potential biomarker for autoregulatory integrity. Incorporating individualized hemodynamic profiling may enhance safety and precision in early stroke rehabilitation protocols.

ClinicalTrials.gov, identifier NCT04573114.