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Recent developments in near-infrared spectroscopy (NIRS) for the assessment of local skeletal muscle microvascular function and capacity to utilise oxygen

View Article: PubMed Central - PubMed

ABSTRACT

Purpose of review: Continuous wave near infrared spectroscopy (CW NIRS) provides non-invasive technology to measure relative changes in oxy- and deoxy-haemoglobin in a dynamic environment. This allows determination of local skeletal muscle O2 saturation, muscle oxygen consumption (V˙O2) and blood flow. This article provides a brief overview of the use of CW NIRS to measure exercise-limiting factors in skeletal muscle.

Recent findings: NIRS parameters that measure O2 delivery and capacity to utilise O2 in the muscle have been developed based on response to physiological interventions and exercise. NIRS has good reproducibility and agreement with gold standard techniques and can be used in clinical populations where muscle oxidative capacity or oxygen delivery (or both) are impaired. CW NIRS has limitations including: the unknown contribution of myoglobin to the overall signals, the impact of adipose tissue thickness, skin perfusion during exercise, and variations in skin pigmentation. These, in the main, can be circumvented through appropriate study design or measurement of absolute tissue saturation.

Summary: CW NIRS can assess skeletal muscle O2 delivery and utilisation without the use of expensive or invasive procedures and is useable in large population-based samples, including older adults.

No MeSH data available.


Related in: MedlinePlus

Example of an arterial (top panel) and a venous (bottom panel) occlusion for ∼30 s, vertical dashed lines show the onset of occlusion and release of cuff.
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fig2: Example of an arterial (top panel) and a venous (bottom panel) occlusion for ∼30 s, vertical dashed lines show the onset of occlusion and release of cuff.

Mentions: An arterial occlusion creates a closed circuit system, no blood flow in or out, so, in the absence of volume change between vascular compartments within the occluded tissue, the rate of decrease in oxy-Hb (or deoxy-Hb increase) represents the muscle , in μM/second (Fig. 2, top panel). During venous occlusion, arterial blood flow is maintained but venous outflow is obstructed until venous pressure exceeds the pressure in the occluding cuff (Fig. 2, bottom panel). In the early quasi-linear phase following inflation of the venous occlusion cuff the rate of increase in deoxy-Hb represents 49 and rate of increase in total Hb signal provides a measurement of resting blood flow.50


Recent developments in near-infrared spectroscopy (NIRS) for the assessment of local skeletal muscle microvascular function and capacity to utilise oxygen
Example of an arterial (top panel) and a venous (bottom panel) occlusion for ∼30 s, vertical dashed lines show the onset of occlusion and release of cuff.
© Copyright Policy - CC BY
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5134760&req=5

fig2: Example of an arterial (top panel) and a venous (bottom panel) occlusion for ∼30 s, vertical dashed lines show the onset of occlusion and release of cuff.
Mentions: An arterial occlusion creates a closed circuit system, no blood flow in or out, so, in the absence of volume change between vascular compartments within the occluded tissue, the rate of decrease in oxy-Hb (or deoxy-Hb increase) represents the muscle , in μM/second (Fig. 2, top panel). During venous occlusion, arterial blood flow is maintained but venous outflow is obstructed until venous pressure exceeds the pressure in the occluding cuff (Fig. 2, bottom panel). In the early quasi-linear phase following inflation of the venous occlusion cuff the rate of increase in deoxy-Hb represents 49 and rate of increase in total Hb signal provides a measurement of resting blood flow.50

View Article: PubMed Central - PubMed

ABSTRACT

Purpose of review: Continuous wave near infrared spectroscopy (CW NIRS) provides non-invasive technology to measure relative changes in oxy- and deoxy-haemoglobin in a dynamic environment. This allows determination of local skeletal muscle O2 saturation, muscle oxygen consumption (V˙O2) and blood flow. This article provides a brief overview of the use of CW NIRS to measure exercise-limiting factors in skeletal muscle.

Recent findings: NIRS parameters that measure O2 delivery and capacity to utilise O2 in the muscle have been developed based on response to physiological interventions and exercise. NIRS has good reproducibility and agreement with gold standard techniques and can be used in clinical populations where muscle oxidative capacity or oxygen delivery (or both) are impaired. CW NIRS has limitations including: the unknown contribution of myoglobin to the overall signals, the impact of adipose tissue thickness, skin perfusion during exercise, and variations in skin pigmentation. These, in the main, can be circumvented through appropriate study design or measurement of absolute tissue saturation.

Summary: CW NIRS can assess skeletal muscle O2 delivery and utilisation without the use of expensive or invasive procedures and is useable in large population-based samples, including older adults.

No MeSH data available.


Related in: MedlinePlus