Original Research ARTICLE
Cerebral microcirculatory blood flow dynamics during rest and a continuous motor task.
- 1Luzerner Kantonsspital, Switzerland
Objectives: To examine the brain’s microcirculatory response on a continuous 5 minutes elbow movement task (EM). Methods: In 24 healthy persons (women 13, men 11, mean age ± SD, 38 ± 11years) we simultaneously recorded cerebral blood flow velocity (CBFV), changes in oxygenated/deoxygenated hemoglobin concentrations ([oxHb], [deoxHb]),, blood pressure (BP), and end-tidal CO2 over 5 minutes epochs of rest and of EM movements of the left elbow at 1 Hz. For analysis transfer function estimates of phase and gain in the low frequency range (0.07-0.15 Hz) was used. Results: ET led to a small BP increase (mean BP at rest 83 mm Hg, at ET 87; p<0.01) and a small ETCO2 decrease (at rest 44.6 mmHg, at EM 41.7 mmHg; p<0.01); it increased BP-[OxHb] phase from 55° (both sides) to 74° (right; p<0.05) / 69° left; p<0.05), and BP-[deoxHb] phase from 264°(right) / 270°(left) to 288° (right; p<0.05) / 297° (left; p=0.09). Cerebral mean transit time (mTT) of around 5.6 seconds remained unchanged. ET decreased BP-CBFV gain significantly on both sides, and BP-CBFV phase only on the right side (p= 0.05). Conclusion: EM leads to an increased time delay between BP and [OxHb] / [deoxHb] leaving cerebral mTT unchanged
Keywords: cererbal microcirculation, cerebral autoregulation, NIRS (near infrared reflectance spectroscopy), Transcranial Doppler (TCD), Motor task performance
Received: 19 Jul 2019;
Accepted: 11 Oct 2019.
Copyright: © 2019 Müller and Oesterreich. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Prof. Martin W. Müller, Luzerner Kantonsspital, Lucerne, Switzerland, email@example.com