Fluid responsiveness and brain tissue oxygen augmentation after subarachnoid hemorrhage.
BACKGROUND
The objective of this study was to investigate the relationship between cardiac index (CI) response to a fluid challenge and changes in brain tissue oxygen pressure (PbtO(2)) in patients with subarachnoid hemorrhage (SAH).


METHODS
Prospective observational study was conducted in a neurological intensive care unit of a university hospital. Fifty-seven fluid challenges were administered to ten consecutive comatose SAH patients that underwent multimodality monitoring of CI, intracranial pressure (ICP), and PbtO(2), according to a standardized fluid management protocol.


RESULTS
The relationship between CI and PbtO(2) was analyzed with logistic regression utilizing generalized estimating equations. Of the 57 fluid boluses analyzed, 27 (47 %) resulted in a ≥ 10 % increase in CI. Median absolute (+5.8 vs. +1.3 mmHg) and percent (20.7 vs. 3.5 %) changes in PbtO(2) were greater in CI responders than in non-responders within 30 min after the end of the fluid bolus infusion. In a multivariable model, a CI response was independently associated with PbtO(2) response (adjusted odds ratio 21.5, 95 % CI 1.4-324, P = 0.03) after adjusting for mean arterial pressure change and end-tidal CO(2). Stroke volume variation showed a good ability to predict CI and PbtO(2) response with areas under the ROC curve of 0.86 and 0.81 with the best cut-off values of 9 % for both responses.


CONCLUSIONS
Bolus fluid resuscitation resulting in augmentation of CI can improve cerebral oxygenation after SAH.
Division of Critical Care Neurology, Department of Neurology, Columbia University, Milstein Hospital 8 Center, 177 Fort Washington Ave, New York, NY, 10032, USA, kurtzpedro@mac.com.
Pedro
P
Kurtz
Raimund
R
Helbok
Sang-Bae
SB
Ko
Jan
J
Claassen
J Michael
JM
Schmidt
Luis
L
Fernandez
R Morgan
RM
Stuart
E Sander
ES
Connolly
Neeraj
N
Badjatia
Stephan A
SA
Mayer
Kiwon
K
Lee
D000328:Adult; D001921:Brain / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000187:drug effects / Q000502:physiology; D005260:Female; D005440:Fluid Therapy / Q000592:standards*; D006439:Hemodynamics / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D007427:Intracranial Pressure / Q000187:drug effects / Q000502:physiology; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods*; D010100:Oxygen / Q000378:metabolism*; D011446:Prospective Studies; D013345:Subarachnoid Hemorrhage / Q000188:drug therapy / Q000378:metabolism / Q000503:physiopathology
D010100:Oxygen