Minhas+et+al_2018_Physiol._Meas._10.1088_1361-6579_aac76b.pdf (1.03 MB)
Download file

Modelling the cerebral haemodynamic response in the physiological range of PaCO2.

Download (1.03 MB)
journal contribution
posted on 04.06.2018, 09:07 by Jatinder Singh Minhas, Ronney B. Panerai, Thompson G. Robinson
Objective Arterial CO2 (PaCO2) has a strong effect on cerebral blood flow (CBF), but its influence on CBF regulatory mechanisms and circulatory systemic variables has not been fully described over the entire physiological range of PaCO2. Approach CBF velocity (CBV, transcranial Doppler), blood pressure (BP, Finometer) and end-tidal CO2 (EtCO2, capnography) were measured in 45 healthy volunteers (19 male, mean age 37.5 years, range 21-71) at baseline, and in response to hypo- (-5mm Hg and -10mm Hg below baseline) and hypercapnia (5% and 8% CO2), applied in random order. Main Results CBV, cerebral dynamic autoregulation index (ARI), heart rate (HR), arterial blood pressure (ABP), critical closing pressure (CrCP) and resistance-area product (RAP) changed significantly (all p<0.0001) for hypo- and hyper-capnia. These parameters were shown to follow a logistic curve relationship representing a 'dose-response' curve for the effects of PaCO2 on the cerebral and systemic circulations. The four logistic model parameters describing each 'dose-response' curve were specific to each of the modelled variables (ANOVA p<0.0001). Significance The ability to model the CBV, ARI, HR, ABP, CrCP and RAP dependency of PaCO2 over its entire physiological range is a powerful tool for physiological and clinical studies, including the need to perform adjustments in disease populations with differing values of baseline PaCO2. .

Funding

JSM is a Dunhill Medical Trust Clinical Research Training Fellow (RTF97/0117) at the Department of Cardiovascular Sciences, University of Leicester. TGR is an NIHR Senior Investigator.

History

Citation

Physiological Measurement, 2018

Author affiliation

/Organisation/COLLEGE OF LIFE SCIENCES/School of Medicine/Department of Cardiovascular Sciences

Version

AM (Accepted Manuscript)

Published in

Physiological Measurement

Publisher

IOP Publishing

issn

0967-3334

eissn

1361-6579

Acceptance date

23/05/2018

Copyright date

2018

Available date

23/05/2019

Publisher version

http://iopscience.iop.org/article/10.1088/1361-6579/aac76b

Notes

The file associated with this record is under embargo until 12 months after publication, in accordance with the publisher's self-archiving policy. The full text may be available through the publisher links provided above.

Language

en

Usage metrics

Categories

Exports