Spontaneous oscillations of arterial blood pressure, cerebral and peripheral blood flow in healthy and comatose subjects

Slow and rhythmic spontaneous oscillations of cerebral and peripheral blood flow occur within frequencies of 0.5-3 min~1 (0.008-0.05 Hz, B-waves) and 3-9 min~1 (0.05-0.15 Hz, M-waves). The generators and pathways of such oscillations are not fully understood. We compared the coefficient of variance...

Full description

Saved in:

Bibliographic Details
Published in:	Neurological research (New York) Vol. 21; no. 7; pp. 665 - 669
Main Authors:	Lang, Erhard W., Dieh, Rolf R., Timmermann, Lars, Baron, Ralf, Deusch, Giinther, Maximilian Mehdorn, H., Zunker, Peter
Format:	Journal Article
Language:	English
Published:	England Taylor & Francis 01-10-1999 Maney Publishing
Subjects:	Adult Blood Pressure - physiology Cerebral autoregulation cerebral circulation Cerebrovascular Circulation - physiology coma Coma - diagnostic imaging Coma - physiopathology covariance analysis Female Humans Male Middle Cerebral Artery - physiology Middle Cerebral Artery - physiopathology Oscillometry peripheral autoregulation Reference Values Regional Blood Flow - physiology transcranial Doppler ultrasound Ultrasonography, Doppler, Transcranial
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Slow and rhythmic spontaneous oscillations of cerebral and peripheral blood flow occur within frequencies of 0.5-3 min~1 (0.008-0.05 Hz, B-waves) and 3-9 min~1 (0.05-0.15 Hz, M-waves). The generators and pathways of such oscillations are not fully understood. We compared the coefficient of variance (CoV), which serves as an indicator for the amplitude of oscillations and is calculated as the percent standard deviation of oscillations within a particular frequency band from the mean, to study the impairment of generators or pathways of such oscillations in normal subjects and comatose patients in a controlled fashion. With local ethic committee approval, data were collected from 19 healthy volunteers and nine comatose patients suffering from severe traumatic brain injury (n = 3), severe subarachnoid hemorrhage (n = 3), and intracerebral hemorrhage (n = 3). Cerebral blood flow velocities were measured by transcranial Doppler ultrasound (TCD), peripheral vasomotion by finger tip laser Doppler flowmetry (LDF), and ABP by either non-invasive continuous blood pressure recordings (Finapres method) in control subjects, or by direct radial artery recordings in comatose patients. Each recording session lasted ~ 20-30 min. Data were stored in the TCD device for offline analysis of CoV. For CoV in the cerebral B-wave frequency range there was no difference between coma patients and controls, however there was a highly significant reduction in the amplitude of peripheral B-wave LDF and ABP vasomotion (3.8 ±2.1 vs. 28.2 ± 76.7 for LDF, p < 0.00 7; and 1.2±0.7 vs. 4.6±2.8 for ABP, p < 0.001) This observation was confirmed for spontaneous cerebral and peripheral oscillations in the M-wave frequency range. The CoV reduction in peripheral LDF and ABP oscillations suggest a severe impairment of the proposed sympathetic pathway in comatose patients. The preservation of central TCD oscillations argues in favor of different pathways and/or generators of cerebral and peripheral B- and M-waves. [Neurol Res 1999; 21: 665-669]
Bibliography:	ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23
ISSN:	0161-6412 1743-1328
DOI:	10.1080/01616412.1999.11740995