Cerebrocortical oxygenation and ventilatory response during sustained hypoxia

David S. Bacon; M. Sherif Afifi; Jack A. Griebel; Enrico M. Camporesi

doi:10.1016/0034-5687(90)90087-F

Cerebrocortical oxygenation and ventilatory response during sustained hypoxia

David S. Bacon, M. Sherif Afifi, Jack A. Griebel, Enrico M. Camporesi^*

^*Corresponding author for this work

Anesthesiology

Research output: Contribution to journal › Article › peer-review

8 Scopus citations

Abstract

Cerebrocortical oxygenation was monitored in 8 healthy adults during exposure to sustained isocapnic hypoxia. Subjects were maintained at an arterial oxygen saturation (Sa_O₂) of 80% for 12 min with a rebreathing circuit while cerebrocortical oxygenation was assessed non-invasively using near-infrared (NIR) spectroscopy to measure changes in the oxidation state of cytochrome a,a₃ (Cyt a,a₃) and changes in cortical blood volume (tBV). During sustained hypoxia, subjects demonstrated a biphasic ventilatory response. The mean ventilation (V̇E) peak response was 255% of baseline at an average of 3.4±0.5 min (mean±SE) after the initiation of hypoxia. A subsequent significant attenuation of V̇E to 163% (P<0.05) of baseline occurred after an additional 8.6 min. NIR monitoring revealed a significant (P<0.05) decrease in oxidized Cyt a,a₃ as well as a significant (P<0.05) increase in tissue blood volume (tBV) at the time of peak V̇E. Both Cyt a, a₃ and tBV remained stable during the remainder of the hypoxic period, despite attenuation of V̇E during sustained hypoxia. The data suggest that cerebrocortical oxygenation and blood flow remain constant when the ventilatory attenuation is observed during sustained hypoxia.

Original language	English (US)
Pages (from-to)	245-257
Number of pages	13
Journal	Respiration Physiology
Volume	80
Issue number	2-3
DOIs	https://doi.org/10.1016/0034-5687(90)90087-F
State	Published - 1990

Keywords

Animal, man
Blood volume in hypoxia, cortical
Control of breathing, isocapnic hypoxia
Cytochrome oxydase, Cyt a,a in brain
Hypoxia, cerebrocortical oxygenation, ventilatory response
Technique on respiratory physiology, near-infrared spectroscopy (NIR)
Ventilation, sensitivity to hypoxia

ASJC Scopus subject areas

Physiology
Pulmonary and Respiratory Medicine

Access to Document

10.1016/0034-5687(90)90087-F

Cite this

@article{49f14750f9994abab61baedba3791c1c,

title = "Cerebrocortical oxygenation and ventilatory response during sustained hypoxia",

abstract = "Cerebrocortical oxygenation was monitored in 8 healthy adults during exposure to sustained isocapnic hypoxia. Subjects were maintained at an arterial oxygen saturation (SaO2) of 80% for 12 min with a rebreathing circuit while cerebrocortical oxygenation was assessed non-invasively using near-infrared (NIR) spectroscopy to measure changes in the oxidation state of cytochrome a,a3 (Cyt a,a3) and changes in cortical blood volume (tBV). During sustained hypoxia, subjects demonstrated a biphasic ventilatory response. The mean ventilation ({\.V}E) peak response was 255% of baseline at an average of 3.4±0.5 min (mean±SE) after the initiation of hypoxia. A subsequent significant attenuation of {\.V}E to 163% (P<0.05) of baseline occurred after an additional 8.6 min. NIR monitoring revealed a significant (P<0.05) decrease in oxidized Cyt a,a3 as well as a significant (P<0.05) increase in tissue blood volume (tBV) at the time of peak {\.V}E. Both Cyt a, a3 and tBV remained stable during the remainder of the hypoxic period, despite attenuation of {\.V}E during sustained hypoxia. The data suggest that cerebrocortical oxygenation and blood flow remain constant when the ventilatory attenuation is observed during sustained hypoxia.",

keywords = "Animal, man, Blood volume in hypoxia, cortical, Control of breathing, isocapnic hypoxia, Cytochrome oxydase, Cyt a,a in brain, Hypoxia, cerebrocortical oxygenation, ventilatory response, Technique on respiratory physiology, near-infrared spectroscopy (NIR), Ventilation, sensitivity to hypoxia",

author = "Bacon, {David S.} and {Sherif Afifi}, M. and Griebel, {Jack A.} and Camporesi, {Enrico M.}",

year = "1990",

doi = "10.1016/0034-5687(90)90087-F",

language = "English (US)",

volume = "80",

pages = "245--257",

journal = "Respiration Physiology",

issn = "0034-5687",

publisher = "Elsevier",

number = "2-3",

}

TY - JOUR

T1 - Cerebrocortical oxygenation and ventilatory response during sustained hypoxia

AU - Bacon, David S.

AU - Sherif Afifi, M.

AU - Griebel, Jack A.

AU - Camporesi, Enrico M.

PY - 1990

Y1 - 1990

N2 - Cerebrocortical oxygenation was monitored in 8 healthy adults during exposure to sustained isocapnic hypoxia. Subjects were maintained at an arterial oxygen saturation (SaO2) of 80% for 12 min with a rebreathing circuit while cerebrocortical oxygenation was assessed non-invasively using near-infrared (NIR) spectroscopy to measure changes in the oxidation state of cytochrome a,a3 (Cyt a,a3) and changes in cortical blood volume (tBV). During sustained hypoxia, subjects demonstrated a biphasic ventilatory response. The mean ventilation (V̇E) peak response was 255% of baseline at an average of 3.4±0.5 min (mean±SE) after the initiation of hypoxia. A subsequent significant attenuation of V̇E to 163% (P<0.05) of baseline occurred after an additional 8.6 min. NIR monitoring revealed a significant (P<0.05) decrease in oxidized Cyt a,a3 as well as a significant (P<0.05) increase in tissue blood volume (tBV) at the time of peak V̇E. Both Cyt a, a3 and tBV remained stable during the remainder of the hypoxic period, despite attenuation of V̇E during sustained hypoxia. The data suggest that cerebrocortical oxygenation and blood flow remain constant when the ventilatory attenuation is observed during sustained hypoxia.

AB - Cerebrocortical oxygenation was monitored in 8 healthy adults during exposure to sustained isocapnic hypoxia. Subjects were maintained at an arterial oxygen saturation (SaO2) of 80% for 12 min with a rebreathing circuit while cerebrocortical oxygenation was assessed non-invasively using near-infrared (NIR) spectroscopy to measure changes in the oxidation state of cytochrome a,a3 (Cyt a,a3) and changes in cortical blood volume (tBV). During sustained hypoxia, subjects demonstrated a biphasic ventilatory response. The mean ventilation (V̇E) peak response was 255% of baseline at an average of 3.4±0.5 min (mean±SE) after the initiation of hypoxia. A subsequent significant attenuation of V̇E to 163% (P<0.05) of baseline occurred after an additional 8.6 min. NIR monitoring revealed a significant (P<0.05) decrease in oxidized Cyt a,a3 as well as a significant (P<0.05) increase in tissue blood volume (tBV) at the time of peak V̇E. Both Cyt a, a3 and tBV remained stable during the remainder of the hypoxic period, despite attenuation of V̇E during sustained hypoxia. The data suggest that cerebrocortical oxygenation and blood flow remain constant when the ventilatory attenuation is observed during sustained hypoxia.

KW - Animal, man

KW - Blood volume in hypoxia, cortical

KW - Control of breathing, isocapnic hypoxia

KW - Cytochrome oxydase, Cyt a,a in brain

KW - Hypoxia, cerebrocortical oxygenation, ventilatory response

KW - Technique on respiratory physiology, near-infrared spectroscopy (NIR)

KW - Ventilation, sensitivity to hypoxia

UR - http://www.scopus.com/inward/record.url?scp=0025277795&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0025277795&partnerID=8YFLogxK

U2 - 10.1016/0034-5687(90)90087-F

DO - 10.1016/0034-5687(90)90087-F

M3 - Article

C2 - 2171123

AN - SCOPUS:0025277795

SN - 0034-5687

VL - 80

SP - 245

EP - 257

JO - Respiration Physiology

JF - Respiration Physiology

IS - 2-3

ER -

Cerebrocortical oxygenation and ventilatory response during sustained hypoxia

Abstract

Keywords

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this