Intracerebral monitoring of silent infarcts after subarachnoid hemorrhage.
BACKGROUND
Silent infarction is common in poor-grade subarachnoid hemorrhage (SAH) patients and associated with poor outcome. Invasive neuromonitoring devices may detect changes in cerebral metabolism and oxygenation.


METHODS
From a consecutive series of 32 poor-grade SAH patients we identified all CT-scans obtained during multimodal neuromonitoring and analyzed microdialysis parameters and brain tissue oxygen tension (PbtO2) preceding CT-scanning.


RESULTS
Eighteen percent of the reviewed head-CTs (12/67) revealed new infarcts. Of the eight infarcts in the vascular territory of the neuromonitoring, seven were clinically silent. Neuromonitoring changes preceding radiological evidence of infarction included lactate-pyruvate-ratio elevation and brain glucose decreases when compared to those with distant or no ischemia (P ≤ 0.03, respectively). PbtO2 was lower, but this did not reach statistical significance.


CONCLUSIONS
These data suggest that there may be distinct changes in brain metabolism and oxygenation associated with the development of silent infarction within the monitored vascular territory in poor-grade SAH patients. Larger prospective studies are needed to determine whether treatment triggered by neuromonitoring data has an impact on outcome.
Division of Critical Care Neurology, Department of Neurology, Columbia University Medical Center, Milstein Hospital 8 Center 177 Fort Washington Ave, New York, NY 10032, USA. raimund.helbok@uki.at
Raimund
R
Helbok
Ravi Chandra
RC
Madineni
Michael J
MJ
Schmidt
Pedro
P
Kurtz
Luis
L
Fernandez
Sang-Bae
SB
Ko
Alex
A
Choi
Morgan R
MR
Stuart
E Sander
ES
Connolly
Kiwon
K
Lee
Neeraj
N
Badjatia
Stephan A
SA
Mayer
Alexander G
AG
Khandji
Jan
J
Claassen
D000328:Adult; D058070:Asymptomatic Diseases; D001921:Brain / Q000378:metabolism; D002544:Cerebral Infarction / Q000175:diagnosis* / Q000378:metabolism* / Q000503:physiopathology; D003422:Critical Care / Q000379:methods; D005260:Female; D005947:Glucose / Q000378:metabolism; D006801:Humans; D019344:Lactic Acid / Q000378:metabolism; D008297:Male; D017551:Microdialysis / Q000379:methods; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods*; D010100:Oxygen / Q000378:metabolism; D019289:Pyruvic Acid / Q000378:metabolism; D012189:Retrospective Studies; D013345:Subarachnoid Hemorrhage / Q000175:diagnosis* / Q000378:metabolism* / Q000503:physiopathology; D014057:Tomography, X-Ray Computed
D019344:Lactic Acid; D019289:Pyruvic Acid; D005947:Glucose; D010100:Oxygen