The cerebral hemodynamics of normotensive hypovolemia during lower-body negative pressure

C. A. Giller, B. D. Levine, Y. Meyer, J. C. Buckey, L. D. Lane, D. J. Borchers

Research output: Contribution to journalArticle

44 Citations (Scopus)

Abstract

Although severe hypovolemia can lead to hypotension and neurological decline, many patients with neurosurgical disorders experience a significant hypovolemia while autonomic compensatory mechanisms maintain a normal blood pressure. To assess the effects of normotensive hypovolemia upon cerebral hemodynamics, transcranial Doppler ultrasound monitoring of 13 healthy volunteers was performed during graded lower-body negative pressure of up to -50 mm Hg, an accepted laboratory model for reproducing the physiological effects of hypovolemia. Middle cerebral artery flow velocity declined by 16% ± 4% (mean ± standard error of the mean) and the ratio between transcranial Doppler ultrasound pulsatility and systemic pulsatility rose 22% ± 8%, suggesting cerebral small-vessel vasoconstriction in response to the sympathetic activation unmasked by lower-body negative pressure. This vasoconstriction may interfere with the autoregulatory response to a sudden fall in blood pressure, and may explain the common observation of neurological deficit during hypovolemia even with a normal blood pressure.

Original languageEnglish (US)
Pages (from-to)961-966
Number of pages6
JournalJournal of Neurosurgery
Volume76
Issue number6
StatePublished - 1992

Fingerprint

Lower Body Negative Pressure
Hypovolemia
Hemodynamics
Doppler Ultrasonography
Blood Pressure
Vasoconstriction
Middle Cerebral Artery
Hypotension
Healthy Volunteers
Observation

Keywords

  • hypovolemia
  • lower-body negative pressure
  • sympathetic nervous system
  • transcranial Doppler ultrasound

ASJC Scopus subject areas

  • Clinical Neurology
  • Neuroscience(all)

Cite this

Giller, C. A., Levine, B. D., Meyer, Y., Buckey, J. C., Lane, L. D., & Borchers, D. J. (1992). The cerebral hemodynamics of normotensive hypovolemia during lower-body negative pressure. Journal of Neurosurgery, 76(6), 961-966.

The cerebral hemodynamics of normotensive hypovolemia during lower-body negative pressure. / Giller, C. A.; Levine, B. D.; Meyer, Y.; Buckey, J. C.; Lane, L. D.; Borchers, D. J.

In: Journal of Neurosurgery, Vol. 76, No. 6, 1992, p. 961-966.

Research output: Contribution to journalArticle

Giller, CA, Levine, BD, Meyer, Y, Buckey, JC, Lane, LD & Borchers, DJ 1992, 'The cerebral hemodynamics of normotensive hypovolemia during lower-body negative pressure', Journal of Neurosurgery, vol. 76, no. 6, pp. 961-966.
Giller, C. A. ; Levine, B. D. ; Meyer, Y. ; Buckey, J. C. ; Lane, L. D. ; Borchers, D. J. / The cerebral hemodynamics of normotensive hypovolemia during lower-body negative pressure. In: Journal of Neurosurgery. 1992 ; Vol. 76, No. 6. pp. 961-966.
@article{e41a582001974a1eabb09513056bef28,
title = "The cerebral hemodynamics of normotensive hypovolemia during lower-body negative pressure",
abstract = "Although severe hypovolemia can lead to hypotension and neurological decline, many patients with neurosurgical disorders experience a significant hypovolemia while autonomic compensatory mechanisms maintain a normal blood pressure. To assess the effects of normotensive hypovolemia upon cerebral hemodynamics, transcranial Doppler ultrasound monitoring of 13 healthy volunteers was performed during graded lower-body negative pressure of up to -50 mm Hg, an accepted laboratory model for reproducing the physiological effects of hypovolemia. Middle cerebral artery flow velocity declined by 16{\%} ± 4{\%} (mean ± standard error of the mean) and the ratio between transcranial Doppler ultrasound pulsatility and systemic pulsatility rose 22{\%} ± 8{\%}, suggesting cerebral small-vessel vasoconstriction in response to the sympathetic activation unmasked by lower-body negative pressure. This vasoconstriction may interfere with the autoregulatory response to a sudden fall in blood pressure, and may explain the common observation of neurological deficit during hypovolemia even with a normal blood pressure.",
keywords = "hypovolemia, lower-body negative pressure, sympathetic nervous system, transcranial Doppler ultrasound",
author = "Giller, {C. A.} and Levine, {B. D.} and Y. Meyer and Buckey, {J. C.} and Lane, {L. D.} and Borchers, {D. J.}",
year = "1992",
language = "English (US)",
volume = "76",
pages = "961--966",
journal = "Journal of Neurosurgery",
issn = "0022-3085",
publisher = "American Association of Neurological Surgeons",
number = "6",

}

TY - JOUR

T1 - The cerebral hemodynamics of normotensive hypovolemia during lower-body negative pressure

AU - Giller, C. A.

AU - Levine, B. D.

AU - Meyer, Y.

AU - Buckey, J. C.

AU - Lane, L. D.

AU - Borchers, D. J.

PY - 1992

Y1 - 1992

N2 - Although severe hypovolemia can lead to hypotension and neurological decline, many patients with neurosurgical disorders experience a significant hypovolemia while autonomic compensatory mechanisms maintain a normal blood pressure. To assess the effects of normotensive hypovolemia upon cerebral hemodynamics, transcranial Doppler ultrasound monitoring of 13 healthy volunteers was performed during graded lower-body negative pressure of up to -50 mm Hg, an accepted laboratory model for reproducing the physiological effects of hypovolemia. Middle cerebral artery flow velocity declined by 16% ± 4% (mean ± standard error of the mean) and the ratio between transcranial Doppler ultrasound pulsatility and systemic pulsatility rose 22% ± 8%, suggesting cerebral small-vessel vasoconstriction in response to the sympathetic activation unmasked by lower-body negative pressure. This vasoconstriction may interfere with the autoregulatory response to a sudden fall in blood pressure, and may explain the common observation of neurological deficit during hypovolemia even with a normal blood pressure.

AB - Although severe hypovolemia can lead to hypotension and neurological decline, many patients with neurosurgical disorders experience a significant hypovolemia while autonomic compensatory mechanisms maintain a normal blood pressure. To assess the effects of normotensive hypovolemia upon cerebral hemodynamics, transcranial Doppler ultrasound monitoring of 13 healthy volunteers was performed during graded lower-body negative pressure of up to -50 mm Hg, an accepted laboratory model for reproducing the physiological effects of hypovolemia. Middle cerebral artery flow velocity declined by 16% ± 4% (mean ± standard error of the mean) and the ratio between transcranial Doppler ultrasound pulsatility and systemic pulsatility rose 22% ± 8%, suggesting cerebral small-vessel vasoconstriction in response to the sympathetic activation unmasked by lower-body negative pressure. This vasoconstriction may interfere with the autoregulatory response to a sudden fall in blood pressure, and may explain the common observation of neurological deficit during hypovolemia even with a normal blood pressure.

KW - hypovolemia

KW - lower-body negative pressure

KW - sympathetic nervous system

KW - transcranial Doppler ultrasound

UR - http://www.scopus.com/inward/record.url?scp=0026740435&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0026740435&partnerID=8YFLogxK

M3 - Article

C2 - 1588430

AN - SCOPUS:0026740435

VL - 76

SP - 961

EP - 966

JO - Journal of Neurosurgery

JF - Journal of Neurosurgery

SN - 0022-3085

IS - 6

ER -