An Automated System for the Measurement of the Response of Cerebral Blood Volume and Cerebral Blood Flow to Changes in Arterial Carbon Dioxide Tension Using Near Infrared Spectroscopy

Elwell, Clare E.; Cope, M; Kirkby, David; Owen-Reece, H; Cooper, Chris E.; Reynolds, E. O. R.; Delpy, David T.

doi:10.1007/978-1-4615-1875-4_19

Cited by 10 publications

(4 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The NIR attenuation spectra were collected contigu ously every second throughout the study, and heart rate, blood pressure, and rectal temperature were logged si multaneously by the NIRS software. The gas mixture fed to the piglets was controlled using a computerised gas blender (Elwell et a!., 1994) and was switched synchro nously with the NIRS data collection. The 31 P spectra were collected contiguously every 10 seconds asynchro nously with respect to the NIRS data collection, and the beginning of each spectrum was logged by the NTR soft ware.…”

Section: Methodsmentioning

confidence: 99%

Oxygen Dependency of Cerebral Oxidative Phosphorylation in Newborn Piglets

Springett

Wylezińska

Cady

et al. 2000

J Cereb Blood Flow Metab

View full text Add to dashboard Cite

Changes in hemoglobin oxygenation and oxidation state of the CuA centre of cytochrome oxidase were measured with full spectral near infrared spectroscopy simultaneously with phosphorus metabolites using nuclear magnetic resonance 31P spectroscopy at high time resolution (10 seconds) during transient anoxia (FiO2 = 0.0 for 105 seconds) in the newborn piglet brain. During the onset of anoxia, there was no change in either phosphocreatine (PCr) concentration or the oxidation state of the CuA centre of cytochrome oxidase until there was a substantial fall in cerebral hemoglobin oxygenation, at which point the CuA centre reduced simultaneously with the decline in PCr. At a later time during the anoxia, intracellular pH decreased rapidly, consistent with a fall in cerebral metabolic rate for O2 and reduced flux through the tricarboxylic acid cycle. The simultaneous reduction of CuA and decline in PCr can be explained in terms of the effects of the falling mitochondrial electrochemical potential. From these observations, it is concluded that, at normoxia, oxidative phosphorylation and the oxidation state of the components of the electron transport chain are independent of cerebral oxygenation and that the reduction in the CuA signal occurs when oxygen tension limits the capacity of oxidative phosphorylation to maintain the phosphorylation potential.

show abstract

Section: Methodsmentioning

confidence: 99%

Oxygen Dependency of Cerebral Oxidative Phosphorylation in Newborn Piglets

Springett

Wylezińska

Cady

et al. 2000

J Cereb Blood Flow Metab

View full text Add to dashboard Cite

show abstract

“…This method of quantifying CBV was first described by Wyatt et al 24 for neonatal applications. In adults the method has extensively been described by Elwell et al 8,25 A 4-wavelength, attenuation-type NIRS instrument (Radiometer Medical A/S, Copenhagen, Denmark) was used. 7,26 The distance of the NIRS optodes was 5.5 cm for all experiments.…”

Section: Nirsmentioning

confidence: 99%

Age dependency of cerebral oxygenation assessed with near infrared spectroscopy

Colier

Haaren

Ven³

et al. 1997

J. Biomed. Opt.

View full text Add to dashboard Cite

Near infrared spectroscopy (NIRS) is an optical technique that provides information on cerebral tissue oxygenation and hemodynamics on a continuous, direct, and noninvasive basis. It is used to determine cerebral blood volume (CBV) and cerebrovascular CO 2 reactivity during normoxic hyper-and hypocapnia in a group of 28 healthy volunteers aged 20 to 83 years. The main focus is on to the age dependency of the measured variables. The influence of changes in minute ventilation during normocapnia on the cerebral oxygenation was also studied. The mean CBV (ϮSD) in age was, for 20 to 30 years, 2.14Ϯ0.51 ml/100 g of brain tissue; for 45 to 50 years, 1.92Ϯ0.40 ml/100 g; and for 70 to 83 years, 1.47Ϯ0.55 ml/100 g. The CBV showed a significant decrease with advancing age. No influence was found for a change in minute ventilation on cerebral oxygenation. During hypercapnia cerebral blood flow (CBF) significantly increased in all age groups, with a factor of 1.31Ϯ0.17 kPa −1 , 1.64Ϯ1.39 kPa −1 , and 2.4Ϯ1.7 kPa −1 , respectively, for the three age groups. The difference in change among the age groups was not statistically significant (pϭ0.09). The trend seen was an increased change in CBF with advancing age. During hypocapnia, the CBF significantly decreased in all age groups, with a factor of 0.89Ϯ0.08 kPa −1 , 0.89Ϯ0.04 kPa −1 , and 0.85Ϯ0.11 kPa −1 , respectively. There was no significant difference among the age groups (pϭ0.50).

show abstract

“…This study was therefore the first applied field research during Alpine skiing to confirm a restricted blood-flow hypothesis using NIRS. Invasive techniques (indocyanide green intravascular tracer) have been used simultaneously with NIRS to reliably measure blood flow in cerebral tissue (Elwell et al, 1994;Roberts et al, 1993) and skeletal muscle tissue (Boushel et al, 2000).…”

Section: Evaluation Of Hemodynamics Using Nirsmentioning

confidence: 99%

Application of Near Infrared Spectroscopy to Exercise Sports Science

Neary¹

2004

Can. J. Appl. Physiol.

View full text Add to dashboard Cite

Over the past 15 years the use of near infrared spectroscopy in exercise and sports science has increased exponentially. The majority of these studies have used this noninvasive technique to provide information related to tissue metabolism during acute exercise. This has been undertaken to determine its utility as a suitable tool to provide new insights into the heterogeneity and regulation of local tissue metabolism, both in cerebral and skeletal muscle tissue. In the accompanying articles in this symposium, issues related to the principles, techniques, limitations (Ferrari et al., 2004), and reliability and validity of NIRS in both cerebral and skeletal muscle tissue (Bhaambhani, 2004), mostly during acute exercise, have been addressed and will not be discussed here. Instead, the present paper will focus specifically on the application of NIRS to exercise sports science, with an emphasis on how this technology has been applied to exercise training and sport, and how it can be used to design training programs for athletes.

show abstract

An Automated System for the Measurement of the Response of Cerebral Blood Volume and Cerebral Blood Flow to Changes in Arterial Carbon Dioxide Tension Using Near Infrared Spectroscopy

Cited by 10 publications

References 21 publications

Oxygen Dependency of Cerebral Oxidative Phosphorylation in Newborn Piglets

Oxygen Dependency of Cerebral Oxidative Phosphorylation in Newborn Piglets

Age dependency of cerebral oxygenation assessed with near infrared spectroscopy

Application of Near Infrared Spectroscopy to Exercise Sports Science

Contact Info

Product

Resources

About