# Cerebral Hemodynamic Alterations in Dialysis COVID-19 Survivors: A Transcranial Doppler Ultrasound Study on Intracranial Pressure Dynamics

## TL;DR

This study found that dialysis patients who survived COVID-19 show altered cerebral blood flow patterns during dialysis, suggesting possible long-term brain and vascular effects of the virus.

## Contribution

The study is the first to use transcranial Doppler ultrasound to investigate cerebral hemodynamic changes in dialysis patients post-COVID-19.

## Key findings

- Post-COVID-19 dialysis patients showed a significant increase in pulsatility index between 30 and 60 minutes of dialysis.
- These patients also exhibited lower heart rates compared to those without prior SARS-CoV-2 infection.

## Abstract

We observed a COVID-19 survivor with a ventriculoperitoneal shunt who developed increased intracranial pressure during hemodialysis. We hypothesized that post-SARS-CoV-2 infection, patients may have altered cerebral perfusion pressure regulation in response to intracranial pressure changes.

From April to July 2021, we recruited dialysis patients with prior COVID-19 from two Madrid nephrology departments. We also recruited age- and sex-matched dialysis patients without prior SARS-CoV-2 infection. Transcranial Doppler ultrasound was used to measure the middle cerebral artery velocity before dialysis and 30, 60, and 90 min after the initiation of dialysis.

The final sample included 37 patients (16 post-COVID-19 and 21 without). The COVID-19 survivors showed a significant pulsatility index increase between 30 and 60 min compared to those without COVID-19. They also had lower heart rates.

We propose two mechanisms: an increase in intracranial pressure or a decreased arterial elasticity. A lower heart rate was also observed in the COVID-19 survivors. This study highlights SARS-CoV-2’s multifaceted effects, including potential long-term vascular and cerebral repercussions.