| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
From the Neurology/Neurosurgery Intensive Care Unit, Washington
University School of Medicine, St Louis, Mo (E.M.M., M.N.D.); Neurovascular
Stroke Service, University of California at San Francisco (D.R.G.); and Acute
Stroke Service and Department of Neurosurgery, Harvard Medical School and
Massachusetts General Hospital, Boston, Mass (L.H.S., C.S.O.).
Correspondence to Edward M. Manno, MD, Washington University School of Medicine, Department of Neurology, Campus Box 8111, 660 S Euclid Ave, St Louis, MO 63110. E-mail mannoe{at}neuro.wustl.edu
Background and
PurposeTranscranial doppler ultrasound (TCD) is used
after subarachnoid hemorrhage to detect cerebral
vasospasm and is often treated with induced hypertension. Cerebral
autoregulation, however, may be disturbed in this population, raising
the possibility that TCD velocities may be elevated by induced
hypertension. To study this possibility, we performed continuous TCD
monitoring of the middle cerebral artery during the induction and
withdrawal of induced hypertension in patients after subarachnoid
hemorrhage.
MethodsTwenty-eight patients were studied during the induction
and withdrawal of hypertension using primarily
phenylephrine. Continuous monitoring was performed on the
middle cerebral artery with the highest flow velocity. Treatment was
based on rising TCD velocities or clinical evidence for cerebral
vasospasm. Mean arterial pressure and mean TCD velocities
were recorded every minute. A change of >15% from starting TCD
values was considered significant. Cerebral autoregulation was
calculated as a percentage of intact autoregulation. Patients were
subsequently divided into groups of disturbed and intact
autoregulation.
ResultsIn 10 of 19 patients (53%), TCD velocities changed by
>15% and paralleled changes in mean arterial
pressure. This directly altered the TCD interpretation of the grade of
vasospasm in 7 of 19 patients (36%). Three additional patients had
smaller absolute changes in TCD velocities. No clinical difference
could be identified between patients with disturbed and intact
autoregulation.
ConclusionsIn patients with disturbed autoregulation after
subarachnoid hemorrhage, induced hypertension can alter
cerebral blood flow velocities. The level of autoregulation needs to be
considered when interpreting TCD velocities in patients after
subarachnoid hemorrhage.
© 1998 American Heart Association, Inc.
Original Contributions
Effects of Induced Hypertension on Transcranial Doppler Ultrasound Velocities in Patients After Subarachnoid Hemorrhage
Key Words: ultrasonography, Doppler subarachnoid hemorrhage hypertension
This article has been cited by other articles:
![]() |
M. Wintermark, N.U. Ko, W.S. Smith, S. Liu, R.T. Higashida, and W.P. Dillon Vasospasm after Subarachnoid Hemorrhage: Utility of Perfusion CT and CT Angiography on Diagnosis and Management AJNR Am. J. Neuroradiol., January 1, 2006; 27(1): 26 - 34. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Krejza, P. Szydlik, D. S. Liebeskind, J. Kochanowicz, O. Bronov, Z. Mariak, and E. R. Melhem Age and Sex Variability and Normal Reference Values for the VMCA/VICA Index AJNR Am. J. Neuroradiol., April 1, 2005; 26(4): 730 - 735. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. F. M. Wijdicks, D. F. Kallmes, E. M. Manno, J. R. Fulgham, and D. G. Piepgras Subarachnoid Hemorrhage: Neurointensive Care and Aneurysm Repair Mayo Clin. Proc., April 1, 2005; 80(4): 550 - 559. [Abstract] [PDF] |
||||
![]() |
A J P Goddard, P P J Raju, and A Gholkar Does the method of treatment of acutely ruptured intracranial aneurysms influence the incidence and duration of cerebral vasospasm and clinical outcome? J. Neurol. Neurosurg. Psychiatry, June 1, 2004; 75(6): 868 - 872. [Abstract] [Full Text] [PDF] |
||||
|
Stroke Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 1998 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |