Dataset Information

Cerebral blood flow changes during tilt table testing in healthy volunteers, as assessed by Doppler imaging of the carotid and vertebral arteries.

ABSTRACT:

Objectives

Using different techniques, reduction of cerebral blood flow (CBF) during orthostatic stress were demonstrated. One study reported flow reduction of the right internal carotid (ICA) and vertebral (VA) artery during orthostatic stress by Doppler imaging, with different effects on the 2 vessels. Global CBF changes, using this technique, have not been reported. Therefore, flow of the ICA, VA and global CBF were measured during head-up tilt testing.

Methods

33 healthy volunteers underwent tilt testing. At three time points (supine, half way and at the end of the test) Doppler imaging of the ICA and VA was performed, as well as PetCO2 measurements.

Results

Global CBF was significantly reduced by 4.5 ± 2.8% halfway the test and by 6.0 ± 3.4% at the end. All 4 artery flows were significantly reduced during the tilt, without differences between them. Despite small changes in PetCO2 there was a significant relation between de CBF decrease and PetCO2 decrease (p < 0.05).

Conclusions

Orthostatic stress in HV results in a small but significant reduction of CBF by a homogenous reduction in the four cerebral vessels and is modulated by PetCO2 changes.

Significance

CBF changes can be measured during tilt testing using Doppler VA and ICA imaging.

SUBMITTER: van Campen CLMC

PROVIDER: S-EPMC6133915 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:ObjectiveThe aim of this study was to compare the hemodynamic effects of manual spinal manipulation (MSM) and instrumental spinal manipulation (ISM) on the vertebral artery (VA) and internal carotid artery (ICA) in participants with chronic nonspecific neck pain (NNP).MethodsThirty volunteers aged 20 to 40 years old with NNP over 3 months duration were included. Participants were randomly divided into the following 2 groups: (1) MSM group (n = 15) and (2) ISM group (n = 15). Ipsilateral (intervention side) and contralateral (opposite side of intervention) VAs and ICAs were evaluated using spectral color Doppler ultrasound before and immediately after manipulation. Measurements were recorded by visualizing the ICA carotid sinus (C4 level) and the VA at the V3 segment (C1-C2 level). The blood flow parameters of peak systolic velocity (PSV), end-diastolic velocity, resistive index, and volume flow (only for VA) were evaluated. The spinal segment, in which biomechanical aberrant movement was detected by palpation in the upper cervical spine, was manually manipulated in the MSM group. The same methodology was performed for the ISM group using an Activator V instrument (Activator Methods).ResultsIntragroup analysis exhibited no statistically significant difference between the MSM and ISM groups in terms of PSV, end-diastolic velocity, resistive index of ipsilateral and contralateral ICA and VA, in addition to volume flow of both VAs preintervention and postintervention (P > .05). Within the intergroup analysis, there was a significant difference in ipsilateral ICA PSV (P = .031) (preintervention vs postintervention difference was -7.9 ± 17.2 cm/s [95% confidence interval, -17.4 to 1.6] in the ISM group and 8.7 ± 22.5 cm/s [95% confidence interval, -3.6 to 21.2]) in the MSM group (P < .05). Other parameters did not show any significant difference (P > .05).ConclusionManual and instrumental spinal manipulations applied to the upper cervical spine in participants with chronic NNP did not appear to alter blood flow parameters of the VAs and ICAs.