Cerebrovascular autoregulation is the mechanism by which changes in cerebral blood flow are prevented during fluctuations in mean arterial blood pressure. Doppler ultrasound measurement of cerebral blood flow velocity provides a reliable indirect technique to estimate cerebral blood flow. In 48 stable preterm infants ≤ 32 weeks gestation, we studied the mean flow velocity in the pericallosal artery at 12, or at 12 and 72 h of age with two-dimensional/pulsed Doppler ultrasound and correlated the mean flow velocity with the simultaneously obtained mean arterial blood pressure values. Mean flow velocity was stable at a mean arterial blood pressure ranging from 31 to 40 mm Hg, but changed proportionally with mean arterial blood pressure values outside this narrow range. Multiple regression analysis showed that mean flow velocity was primarily determined by mean arterial blood pressure. These data suggest that in preterm infants regulation of cerebral blood flow velocity occurs only over a narrow range of mean arterial blood pressure values.

Keywords:
Cerebral blood flow velocity, Pericallosal artery, Pulsed Doppler ultrasound, Arterial blood pressure, Preterm infants
This content is only available via PDF.
© 1991 S. Karger AG, Basel
1991
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.