Frontal Cerebral Oxygenation in Humans at Rest: A Mirror Symmetry in the Correlation with Cardiorespiratory Activity

Felix Scholkmann; Hamoon Zohdi; Martin Wolf; Ursula Wolf

doi:10.1007/978-3-031-14190-4_8

Frontal Cerebral Oxygenation in Humans at Rest: A Mirror Symmetry in the Correlation with Cardiorespiratory Activity

Adv Exp Med Biol. 2022:1395:45-51. doi: 10.1007/978-3-031-14190-4_8.

Authors

Felix Scholkmann^{1

2}, Hamoon Zohdi³, Martin Wolf⁴, Ursula Wolf³

Affiliations

¹ Institute of Complementary and Integrative Medicine, University of Bern, Bern, Switzerland. Felix.Scholkmann@unibe.ch.
² Biomedical Optics Research Laboratory, Department of Neonatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland. Felix.Scholkmann@unibe.ch.
³ Institute of Complementary and Integrative Medicine, University of Bern, Bern, Switzerland.
⁴ Biomedical Optics Research Laboratory, Department of Neonatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.

PMID: 36527612
DOI: 10.1007/978-3-031-14190-4_8

Abstract

Background: Although several studies published reference values for frontal cerebral tissue oxygen saturation (StO₂) measured with near-infrared spectroscopy (NIRS) based cerebral oximetry, a detailed investigation, whether and which factors from systemic physiology are related to the individual StO₂ values, is missing.

Aim: We investigated how the state of the cardiorespiratory system is linked to StO₂ values at rest.

Subjects and methods: Absolute StO₂ values (median over a 5 min resting-phase while sitting) were obtained from 126 healthy subjects (age: 24.0 ± 0.2 years, 45 males, 81 females) over the left and right prefrontal cortex (PFC) by employing frequency-domain NIRS as part of a systemic physiology augmented functional near-infrared spectroscopy (SPA-fNIRS) study. In addition, heart rate (HR) and respiration rate (RR) were measured, and the pulse respiration quotient (PRQ) was determined (PRQ = HR/RR). General additive models (GAM) were used to analyse the data.

Results: The GAM analysis revealed a specific relationship between the overall PFC StO₂ values (mean over right and left PFC) and the variables HR and RR: HR was positively correlated with mean StO₂, while RR showed no correlation. In the mirror case, RR was negatively linearly correlated with the frontal cerebral oxygenation asymmetry (FCOA), which was not correlated with HR. The right PFC StO₂ was not linked to the RR, whereas the left PFC StO₂ was. Positive correlations of the PRQ with the mean PFC StO₂ as well as the FCOA were also found. GAM modelling revealed that the individual FCOA values are explained to a large extent (deviance explained: 88.8%) by the individual mean PFC StO₂ and PRQ. We conclude that (i) the state of the cardiorespiratory system is significantly correlated with StO₂ values and (ii) there is a mirror symmetry with regard to the impact of cardiorespiratory parameters on the mean PFC StO₂ and FCOA.

Keywords: Cardiorespiratory activity; Frontal cerebral tissue oxygen saturation; NIRS; SPA-fNIRS.

MeSH terms

Adult
Cerebrovascular Circulation
Female
Heart Rate
Humans
Male
Oximetry* / methods
Oxygen
Oxygen Consumption* / physiology
Spectroscopy, Near-Infrared / methods
Young Adult

Substances

Oxygen