Citation

Len TK, Neary JP, Asmundson GJ, Candow DG, Goodman DG, Bjornson B, Bhambhani YN. Brain Inj. 2013; 27(3): 346-353.

Affiliation

Faculty of Kinesiology and Health Studies, University of Regina , Saskatchewan , Canada.

Copyright

(Copyright © 2013, Informa - Taylor and Francis Group)

DOI

10.3109/02699052.2012.743185

PMID

23438354

Abstract

Primary objective: This study examined the effects of mild traumatic brain injury (mTBI) on cerebrovascular reactivity (CVR). Research design: A repeated measures design was used to examine serial changes in CVR. Methods and procedures: Twenty subjects who recently suffered a mTBI were subjected to a respiratory challenge consisting of repeated 20 s breath-holds (BH) and hyperventilations (HV). Testing occurred on days 2 (D2), 4 (D4) and 8 (D8) post-injury as well as a baseline (BASE) assessment (after return-to-play). Transcranial Doppler was used to assess mean cerebral blood velocity (vMCA) and expired gas analysis provided end-tidal carbon dioxide (PETCO(2)) levels. Results: There was no significant difference in resting vMCA across all testing days for mTBI. No significant differences in PETCO(2) were found throughout the testing protocol. A significant effect (p < 0.001) of testing day on vMCA was found during BH and HV challenges for mTBI. Post-hoc analysis revealed significant differences (p < 0.05) in vMCA between D2 and the other testing days. Conclusions: These data suggest that, following mTBI: (1) CVR is not impaired at rest; (2) CVR is impaired in response to respiratory stress; and (3) the impairment may be resolved as early as 4 days post-injury.

Language: en