Skip Navigation LinksHome > December 2011 - Volume 43 - Issue 12 > Cerebrovascular Reactivity Impairment after Sport-Induced Co...
Medicine & Science in Sports & Exercise:
doi: 10.1249/MSS.0b013e3182249539
Clinical Sciences

Cerebrovascular Reactivity Impairment after Sport-Induced Concussion

LEN, TREVOR K.1; NEARY, J. PATRICK1; ASMUNDSON, GORDON J. G.2; GOODMAN, DAVID G.3; BJORNSON, BRUCE4; BHAMBHANI, YAGESH N.5

Collapse Box

Abstract

Purpose: This study evaluated cerebrovascular reactivity (CVR) after a sport-induced concussion, also called mild traumatic brain injury (mTBI), by monitoring middle cerebral artery blood velocity (vMCA) with transcranial Doppler ultrasonography and simultaneous end-tidal carbon dioxide (PETCO2) measurements.

Methods: Thirty-one athletes (16–25 yr old) participated in this study. The participants were divided into two groups—healthy (n = 21) and mTBI (n = 10). Participants in the mTBI group suffered an mTBI within the last 7 d (x― = 4.5 ± 1.1 d). Outcome measures included vMCA and PETCO2 in response to breath holding (5 × 20 s, 40-s rest) and hyperventilation (5 × 20 s, 40-s rest).

Results: Resting vMCA values between groups were not significantly different. Percentage change of vMCA was significantly different after the recovery period of the second hyperventilation (P = 0.034). mTBI subjects failed to return to resting levels after each breath hold. PETCO2 changes mirrored the vMCA changes.

Conclusions: These data suggest that normal CVR responses may be disrupted in the days immediately after occurrence of mTBI. Transcranial Doppler ultrasonography combined with expired gas measurements provides a useful method for assessing CVR impairment after mTBI. Further research, including serial monitoring after mTBI and analysis of CVR response to exercise, is warranted before any firm conclusions can be drawn.

©2011The American College of Sports Medicine

Login

Article Tools

Share

Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.

Connect With Us