Measurement of hemoglobin flow and blood flow by near-infrared spectroscopy

Edwards, Anthony; Richardson, C. E.; Zee, Pieter van der; Elwell, Clare E.; Wyatt, John; Cope, M; Delpy, DT; Reynolds, E. O. R.

doi:10.1152/jappl.1993.75.4.1884

Cited by 130 publications

(69 citation statements)

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“…Regional limb blood-flow measurements have been performed using electromagnetic flow meters (Cronestrand,888 G. Rådegran (Lassen et al 1964), microdialysis (Hickner et al 1994a;, near i.r. spectroscopy (NIRS; Edwards et al 1993;Boushel et al 1997), positron emission tomography (PET; Ruotsalainen et al 1997), and laser Doppler (Jensen et al 1995). In addition, drop or volume counting, hot-wire anemometer and radioactively-labelled microsphere techniques have been used in animals.…”

Section: Blood Flow: Exercise: Muscle Metabolism: Hyperaemiamentioning

confidence: 99%

“…NIRS allows measurements to be made of concentration changes of oxyhaemoglobin, deoxyhaemoglobin and total haemoglobin in local muscle regions. Changes in these concentrations were previously used as a measure of local muscle blood flow (Edwards et al 1993;De Blasi et al 1994). However, as blood flow and delivery of O 2 to the muscle may be independent of the O 2 consumption the NIRS-ICG procedure is a better concept for estimating local blood flow.…”

Section: Near Ir Spectroscopymentioning

confidence: 99%

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Limb and skeletal muscle blood flow measurements at rest and during exercise in human subjects

Rådegran

1999

Proc. Nutr. Soc.

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Abbreviations: ∆f, Doppler frequency shift that occurs as transmitted sound waves of a specific frequency f are reflected by erythrocytes; ICG, indo-cyanine green; NIRS, near i.r. spectroscopy; PET, positron emission tomography. The aim of the present review is to present techniques used for measuring blood flow in human subjects and advice as to when they may be applicable. Since blood flow is required to estimate substrate fluxes, energy turnover and metabolic rate of skeletal muscle, accurate measurements of blood flow are of extreme importance. Several techniques have therefore been developed to enable estimates to be made of the arterial inflow to, venous outflow from, or local blood flow within the muscle. Regional measurements have been performed using electromagnetic flow meters, plethysmography, indicator methods (e.g. thermodilution and indo-cyanine green dye infusion), ultrasound Doppler, and magnetic resonance velocity imaging. Local estimates have been made using 133 Xe clearance, microdialysis, near i.r. spectroscopy, positron emission tomography and laser Doppler. In principle, the aim of the study, the type of interventions and the limitations of each technique determine which method may be most appropriate. Ultrasound Doppler and continuous indo-cyanine green dye infusion gives the most accurate limb blood flow measurements at rest. Moreover, the ultrasound Doppler is unique, as it does not demand a steadystate, and because its high temporal resolution allows detection of normal physiological variations as well as continuous measurements during transitional states such as at onset of and in recovery from exercise. During steady-state exercise thermodilution can be used in addition to indo-cyanine green dye infusion and ultrasound Doppler, where the latter is restricted to exercise modes with a fixed vessel position. Magnetic resonance velocity imaging may in addition be used to determine blood flow within deep single vessels. Positron emission tomography seems to be the most promising tool for local skeletal muscle blood-flow measurements in relation to metabolic activity, although the mode and intensity of exercise will be restricted by the apparatus design.

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Section: Blood Flow: Exercise: Muscle Metabolism: Hyperaemiamentioning

confidence: 99%

Section: Near Ir Spectroscopymentioning

confidence: 99%

Limb and skeletal muscle blood flow measurements at rest and during exercise in human subjects

Rådegran

1999

Proc. Nutr. Soc.

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“…Near-infrared spectroscopy relies on the observation that blood flow can be quantified by relating the concentration of a tracer molecule to the rate of tracer accumulation under certain conditions. Endogenous compounds, such as hemoglobin and myoglobin, are used as tracers because they are not degraded quickly and can be detected accurately [Edwards et al, 1993].…”

Section: Measurements Of Regional Blood Flows With Venous Occlusion Pmentioning

confidence: 99%

“…However, the method appears to exhibit a high correlation with venous occlusion plethysmography [Edwards et al, 1993;De Blasi et al, 1994]. Nearinfrared spectroscopy can potentially be used to assess blood flows to exercising skeletal muscles, after ischemia and during intra-arterial infusion of vasoactive compounds [Nioka et al, 2006].…”

Section: Measurements Of Regional Blood Flows With Venous Occlusion Pmentioning

confidence: 99%

Sympathetic Vascular Tone in Human Obesity

Agapitov

Sinkey

Dopp

et al. 2004

Journal of Hypertension

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Obesity is associated with increased sympathoactivation that elevates arterial pressure. However, the mechanism linking sympathetic activation to arterial pressure is unclear. Specifically, it has never been demonstrated unequivocally that sympathetically mediated vasoconstriction is increased in obesity. This project tested the hypothesis that sympathetic vascular tone is increased in obese normotensive and hypertensive subjects.The effect of weight loss on sympathetic vascular tone was also assessed.Sympathetic vascular tone was assessed as forearm vasodilatation to intra-arterial phentolamine (α 1/2 -adrenergic receptor antagonist). Pharmacological responses were correlated with skeletal muscle sympathetic nerve activity (mSNA). Obese subjects with and without hypertension had increased mSNA. However, the vasodilatator response to phentolamine was not augmented in obese normotensive and hypertensive subjects versus lean controls. Additionally, weight loss did not alter phentolamine's vasodilatator response, despite reducing mSNA and arterial pressure in obese groups. These results indicate that sympathetic vascular tone is not increased in obesity despite higher mSNA.These studies also assessed forearm resistance vessel function using intra-arterial nitroprusside (nitric oxide donor) and isoproterenol (β 2 -adrenergic receptor agonist). The effects of weight loss on these responses were studied in the obese groups. The response to both vasodilators was blunted, but only in obese hypertensive subjects. Weight loss normalized the response to nitroprusside but not to isoproterenol. This result suggests that obesity-related hypertension is associated with vascular smooth muscle dysfunction, which can be improved by weight loss. Blunted vasodilatation to isoproterenol suggests an abnormality on β 2 -adrenergic receptor-dependent mechanisms that may or may not depend on the endothelium. Also, mental stress-induced forearm vasodilatation was blunted in obese normotensive subjects, which was not normalized by weight loss. 2In conclusion, increased sympathetic nerve activity does not augment forearm sympathetic vascular tone. This dissociation could be due to opposing local factors (e.g. insulin, leptin) or to a different target of limb sympathoactivation (e.g. adipocytes vs. vascular). Sympathetic drive to tissues other than the peripheral circulation may play a more important role in arterial pressure elevation in obesity, either directly or indirectly.Abstract Approved: ____________________________________ Thesis Supervisor ____________________________________

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“…NIRS and NIRI are applied in many clinical applications, using different types of instruments to track oxygenation and blood flow in tissue [14][15][16][17][18][19][20][21][22][23][24][25][26][27]. Many of these applications could profit from textile integrated optic devices, as described in [22].…”

Section: Introductionmentioning

confidence: 99%

Textile integrated sensors and actuators for near-infrared spectroscopy

Zysset¹,

Nasseri²,

Büthe³

et al. 2013

Opt. Express

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Being the closest layer to our body, textiles provide an ideal platform for integrating sensors and actuators to monitor physiological signals. We used a woven textile to integrate photodiodes and light emitting diodes. LEDs and photodiodes enable near-infrared spectroscopy (NIRS) systems to monitor arterial oxygen saturation and oxygenated and deoxygenated hemoglobin in human tissue. Photodiodes and LEDs are mounted on flexible plastic strips with widths of 4 mm and 2 mm, respectively. The strips are woven during the textile fabrication process in weft direction and interconnected with copper wires with a diameter of 71 m in warp direction. The sensor textile is applied to measure the pulse waves in the fingertip and the changes in oxygenated and deoxygenated hemoglobin during a venous occlusion at the calf. The system has a signal-to-noise ratio of more than 70 dB and a system drift of 0.37% ± 0.48%. The presented work demonstrates the feasibility of integrating photodiodes and LEDs into woven textiles, a step towards wearable health monitoring devices. Abstract: Being the closest layer to our body, textiles provide an ideal platform for integrating sensors and actuators to monitor physiological signals. We used a woven textile to integrate photodiodes and light emitting diodes. LEDs and photodiodes enable near-infrared spectroscopy (NIRS) systems to monitor arterial oxygen saturation and oxygenated and deoxygenated hemoglobin in human tissue. Photodiodes and LEDs are mounted on flexible plastic strips with widths of 4 mm and 2 mm, respectively. The strips are woven during the textile fabrication process in weft direction and interconnected with copper wires with a diameter of 71 μm in warp direction. The sensor textile is applied to measure the pulse waves in the fingertip and the changes in oxygenated and deoxygenated hemoglobin during a venous occlusion at the calf. The system has a signalto-noise ratio of more than 70 dB and a system drift of 0.37% ± 0.48%. The presented work demonstrates the feasibility of integrating photodiodes and LEDs into woven textiles, a step towards wearable health monitoring devices. ©2013 Optical Society of America

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Measurement of hemoglobin flow and blood flow by near-infrared spectroscopy

Cited by 130 publications

References 0 publications

Limb and skeletal muscle blood flow measurements at rest and during exercise in human subjects

Limb and skeletal muscle blood flow measurements at rest and during exercise in human subjects

Sympathetic Vascular Tone in Human Obesity

Textile integrated sensors and actuators for near-infrared spectroscopy

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