Dynamic cerebral autoregulation changes during sub-maximal handgrip maneuver..pdf (1.08 MB)
Download file

Dynamic Cerebral Autoregulation Changes during Sub-Maximal Handgrip Maneuver

Download (1.08 MB)
journal contribution
posted on 14.07.2015, 14:34 by R. C. Nogueira, E. Bor-Seng-Shu, M. R. Santos, C. E. Negrão, M. J. Teixeira, Ronney B. Panerai
PURPOSE: We investigated the effect of handgrip (HG) maneuver on time-varying estimates of dynamic cerebral autoregulation (CA) using the autoregressive moving average technique. METHODS: Twelve healthy subjects were recruited to perform HG maneuver during 3 minutes with 30% of maximum contraction force. Cerebral blood flow velocity, end-tidal CO₂ pressure (PETCO₂), and noninvasive arterial blood pressure (ABP) were continuously recorded during baseline, HG and recovery. Critical closing pressure (CrCP), resistance area-product (RAP), and time-varying autoregulation index (ARI) were obtained. RESULTS: PETCO₂ did not show significant changes during HG maneuver. Whilst ABP increased continuously during the maneuver, to 27% above its baseline value, CBFV raised to a plateau approximately 15% above baseline. This was sustained by a parallel increase in RAP, suggestive of myogenic vasoconstriction, and a reduction in CrCP that could be associated with metabolic vasodilation. The time-varying ARI index dropped at the beginning and end of the maneuver (p<0.005), which could be related to corresponding alert reactions or to different time constants of the myogenic, metabolic and/or neurogenic mechanisms. CONCLUSION: Changes in dynamic CA during HG suggest a complex interplay of regulatory mechanisms during static exercise that should be considered when assessing the determinants of cerebral blood flow and metabolism.

History

Citation

PLoS One, 2013, 8 (8), e70821

Author affiliation

/Organisation/COLLEGE OF MEDICINE, BIOLOGICAL SCIENCES AND PSYCHOLOGY/School of Medicine/Department of Cardiovascular Sciences

Version

VoR (Version of Record)

Published in

PLoS One

Publisher

Public Library of Science

eissn

1932-6203

Acceptance date

23/06/2013

Copyright date

2013

Available date

14/07/2015

Publisher version

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0070821

Language

en