Cerebral blood flow velocity and inflammatory response after severe traumatic brain injury.
OBJECTIVE
The cerebral blood flow velocity (CBVF) was measured by transcranial Doppler sonography in patients with severe traumatic brain injury (TBI) in order to determine, whether it depends on the posttraumatic inflammatory response.


METHODS
CBVF in both middle cerebral arteries (MCA) was recorded in 25 comatous TBI patients (male 20; female five; mean age +/- standard deviation (S.D.), 41 +/- 20 years) and correlated to the levels of interleukine-(IL) 6, IL-8 and IL-10 in corresponding CSF/plasma samples, to PaCO2 and to intracranial (ICP), mean arterial (MAP) and cranial perfusion pressure (CPP).


RESULTS
CSF IL-6 and IL-8 were clearly higher than the corresponding plasma levels (mean CSF/plasma quotient for IL-6: 159 +/- 582; for IL-8: 143 +/- 311). CBVF did not show large side-to-side differences at each examination indicating that CBFV in both MCAs was determined mostly by systemic conditions and not by severe regional abnormalities. Since all other evaluated variables including interleukines represent also systemic conditions we used the mean value (MCBFV) of both CBFVs for analysis. By stepwise regression analysis between MCBVF (mean +/- S.D., 80 +/- 26 cm/s) and the variables PaCO2 (33 +/- 4 mmHg), MAP (86 +/- 12 mmHg), ICP (20 +/- 11 mmHg), CPP (70 +/- 14 mmHg) and CSF or plasma IL-6, IL-8 and IL-10, it turned out that MCBFV correlated significantly with PaCO2 (r = 0.478; P < 0.01) and CSF IL-8 (r = -0.361; P < 0.05).


CONCLUSIONS
When CPP is adequate for brain perfusion, CBFV in large brain supplying arteries depends predominantly on PaCO2 and shows only a slight association to intrathecal IL-8 levels. For clinical interpretation of CBFV data, the inflammatory response seems to be of minor relevance.
Müller
M
M
Department of Neurology, University Hospital of the Saarland, Kirrberger Str. D-66421, Homburg/Saar, Hamburg, Germany. nemmue@med-rz.uni-sb.de
Schwerdtfeger
K
K
Maier
B
B
Mautes
A
A
Schiedat
T
T
Bianchi
O
O
Marzi
I
I
D000328:Adult; D001783:Blood Flow Velocity; D001794:Blood Pressure; D001930:Brain Injuries / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000503:physiopathology; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism*; D016753:Interleukin-10 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism; D007378:Interleukins / Q000097:blood / Q000134:cerebrospinal fluid / Q000378:metabolism*; D007427:Intracranial Pressure; D008297:Male; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging; D017585:Ultrasonography, Doppler, Transcranial
D018836:Inflammation Mediators; D015850:Interleukin-6; D016209:Interleukin-8; D007378:Interleukins; D016753:Interleukin-10