Blood volume vs. deoxygenated NIRS signal: computational analysis of the effects muscle O2 delivery and blood volume on the NIRS signals

2021 ◽  
Author(s):  
Bhabuk Koirala ◽  
Alessandro Concas ◽  
Yi Sun ◽  
L. Bruce Gladden ◽  
Nicola Lai
Keyword(s):  
Blood Volume ◽  
Computational Analysis ◽  
Near Infrared ◽  
Canine Model ◽  
Normal Delivery ◽  
Contracting Muscle ◽  
Muscle Oxygen ◽  
Key Factor ◽  
Nirs Signal ◽  
Concentration Changes

Near-infrared spectroscopy (NIRS) signals quantify the oxygenated (ΔHbMbO2) and deoxygenated (ΔHHbMb) heme group concentrations. ΔHHbMb has been preferred to ΔHbMbO2 in evaluating skeletal muscle oxygen extraction because it is assumed to be insensitive to blood volume (BV) changes, but uncertainties exist on this assumption. To analyze this assumption a computational model of oxygen transport and metabolism is used to quantify the effect of O2 delivery and BV changes on the NIRS signals from a canine model of muscle oxidative metabolism (Med.Sci.SportsExerc.,48(10)2013-2020,2016). The computational analysis accounts for microvascular (ΔHbO2, ΔHHb) and extravascular (ΔHMb, ΔHMb) oxygenated and deoxygenated forms. Simulations predicted muscle oxygen uptake and NIRS signal changes well for blood flows ranging from resting to contracting muscle. Additional NIRS signal simulations were obtained in the absence or presence of BV changes corresponding to a heme groups concentration changes (ΔHbMb=0-48μM). Under normal delivery (Q=1.0L kg-1min-1) of contracting muscle, capillary oxygen saturation (SO2) was 62% with capillary ΔHbO2 and ΔHHb of ±41μM for ΔHbMb=0. An increase of BV (ΔHbMb =24mM) caused a ΔHbO2 decrease (16mM) almost twice as much as the increase observed for ΔHHb (9μM). When SO2 increased to more than 80%, only ΔHbO2 was significantly affected by BV changes. The analysis indicates that microvascular SO2 is a key factor in determining the sensitivity of ΔHbMbO2 and ΔHHbMb to BV changes. Contrary to a common assumption, the ΔHHbMb is affected by BV changes in normal contracting muscle and even more in the presence of impaired O2 delivery.

scholarly journals Increased tissue oxygenation explains the attenuation of hyperemia upon repetitive pneumatic compression of the lower leg

2017 ◽  
Vol 123 (6) ◽  
pp. 1451-1460 ◽  
Author(s):  
Alessandro Messere ◽  
Gianluca Ceravolo ◽  
Walter Franco ◽  
Daniela Maffiodo ◽  
Carlo Ferraresi ◽  
...  
Keyword(s):  
Blood Flow ◽  
Blood Volume ◽  
Near Infrared ◽  
Tissue Oxygenation ◽  
Femoral Vein ◽  
Lower Leg ◽  
Local Circulation ◽  
Doppler Measurement ◽  
Key Factor ◽  
Interstimulus Intervals

The rapid hyperemia evoked by muscle compression is short lived and was recently shown to undergo a rapid decrease even in spite of continuing mechanical stimulation. The present study aims at investigating the mechanisms underlying this attenuation, which include local metabolic mechanisms, desensitization of mechanosensitive pathways, and reduced efficacy of the muscle pump. In 10 healthy subjects, short sequences of mechanical compressions ( n = 3–6; 150 mmHg) of the lower leg were delivered at different interstimulus intervals (ranging from 20 to 160 s) through a customized pneumatic device. Hemodynamic monitoring included near-infrared spectroscopy, detecting tissue oxygenation and blood volume in calf muscles, and simultaneous echo-Doppler measurement of arterial (superficial femoral artery) and venous (femoral vein) blood flow. The results indicate that 1) a long-lasting (>100 s) increase in local tissue oxygenation follows compression-induced hyperemia, 2) compression-induced hyperemia exhibits different patterns of attenuation depending on the interstimulus interval, 3) the amplitude of the hyperemia is not correlated with the amount of blood volume displaced by the compression, and 4) the extent of attenuation negatively correlates with tissue oxygenation ( r = −0,78, P < 0.05). Increased tissue oxygenation appears to be the key factor for the attenuation of hyperemia upon repetitive compressive stimulation. Tissue oxygenation monitoring is suggested as a useful integration in medical treatments aimed at improving local circulation by repetitive tissue compression. NEW & NOTEWORTHY This study shows that 1) the hyperemia induced by muscle compression produces a long-lasting increase in tissue oxygenation, 2) the hyperemia produced by subsequent muscle compressions exhibits different patterns of attenuation at different interstimulus intervals, and 3) the extent of attenuation of the compression-induced hyperemia is proportional to the level of oxygenation achieved in the tissue. The results support the concept that tissue oxygenation is a key variable in blood flow regulation.

scholarly journals Interpretation of Near-Infrared Spectroscopy (NIRS) Signals in Skeletal Muscle

2019 ◽  
Author(s):  
Adeola A. Sanni ◽  
Kevin K. McCully
Keyword(s):  
Skeletal Muscle ◽  
Oxygen Saturation ◽  
Blood Volume ◽  
Near Infrared ◽  
Continuous Wave ◽  
Muscle Oxygen ◽  
Significant Difference ◽  
Forearm Flexor Muscles ◽  
The Difference ◽  
Forearm Flexor

NIRS uses the relative absorption of light at 850nm and 760nm, to determine skeletal muscle oxygen saturation. Previous studies have used the ratio of both signals to report muscle oxygen saturation. Purpose: To evaluate the different approaches used to represent muscle oxygen saturation, and to evaluate the pulsations of the O2heme and Heme signal. Method: Twelve participants, ages 20-29years were tested on the forearm flexor muscles using continuous wave NIRS at rest. Measurements were taken during 2-3mins rest, during physiological calibration (5-minuts Ischemia) and during reperfusion.&nbsp; Results: There was a significant difference in pulse size between O2heme and Heme signal at the three locations (p &lt; 0.05). Resting oxygen saturation was 58.8+9.2%, 69.6+3.9%, and 89.2+6.9% when calibrated using O2heme, TSI, and Heme, respectively.&nbsp; Conclusion: The difference in magnitude of O2heme and Heme pulse with each heartbeat might suggest different anatomical locations of these signals, which propose calibrating with just one of the signals instead of the ratio of both. Calculations of physiological calibration must account for increased blood volume in the tissue, because of the changes in blood volume which appear to be primarily from the O2heme signal. Resting oxygen levels calibrated with Heme agrees with theoretical oxygen saturation.

scholarly journals Interpretation of Near-Infrared Spectroscopy (NIRS) Signals in Skeletal Muscle

2019 ◽  
Vol 4 (2) ◽  
pp. 28
Author(s):  
Adeola A. Sanni ◽  
Kevin K. McCully
Keyword(s):  
Skeletal Muscle ◽  
Infrared Spectroscopy ◽  
Oxygen Saturation ◽  
Blood Volume ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Continuous Wave ◽  
Saturation Index ◽  
Muscle Oxygen ◽  
Significant Difference

Near-infrared spectroscopy (NIRS) uses the relative absorption of light at 850 and 760 nm to determine skeletal muscle oxygen saturation. Previous studies have used the ratio of both signals to report muscle oxygen saturation. Purpose: The purpose of this pilot study is to assess the different approaches used to represent muscle oxygen saturation and to evaluate the pulsations of oxygenated hemoglobin/myoglobin (O2heme) and deoxygenated hemoglobin/myoglobin (Heme) signals. Method: Twelve participants, aged 20–29 years, were tested on the forearm flexor muscles using continuous-wave NIRS at rest. Measurements were taken during 2–3 min rest, physiological calibration (5 min ischemia), and reperfusion. Ten participants were included in the study analysis. Results: There was a significant difference in pulse size between O2heme and Heme signals at the three locations (p < 0.05). Resting oxygen saturation was 58.8% + 9.2%, 69.6% + 3.9%, and 89.2% + 6.9% when calibrated using O2heme, the tissue oxygenation/saturation index (TSI), and Heme, respectively. Conclusion: The difference in magnitude of O2heme and Heme pulses with each heartbeat might suggest different anatomical locations of these signals, for which calibrating with just one of the signals instead of the ratio of both is proposed. Calculations of physiological calibration must account for increased blood volume in the tissue because of the changes in blood volume, which appear to be primarily from the O2heme signal. Resting oxygen levels calibrated with Heme agree with theoretical oxygen saturation.

Measuring Real-Time Physiological Changes by near Infrared Spectroscopy

2014 ◽  
Vol 687-691 ◽  
pp. 974-977
Author(s):  
Yu Xiang Wu ◽  
Min Fang Huang ◽  
Tao Song ◽  
Guo Dong Xu
Keyword(s):  
Infrared Spectroscopy ◽  
Real Time ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Hemoglobin Concentration ◽  
Muscle Oxygen ◽  
Sport Training ◽  
Concentration Changes ◽  
Oxygen Monitoring ◽  
Scientific Fields

Near infrared spectroscopy is a promising technique in many scientific fields, but it is still a new measurement in sport science, of which coaches and athletes cannot make good use. In this paper we demonstrate how the real-time physiological oxygenated hemoglobin and deoxygenated hemoglobin concentration changes in the muscle can be measured noninvasively by near infrared spectroscopy and explain what the advantages of it is. The purpose is to reveal the mechanism and potential of muscle oxygen monitoring, which may play an important role in sport training.

Psychophysiological Responses to Stress Related to Anxiety in Healthy Aging

2019 ◽  
Vol 33 (3) ◽  
pp. 188-197 ◽  
Author(s):  
Roberta Adorni ◽  
Agostino Brugnera ◽  
Alessia Gatti ◽  
Giorgio A. Tasca ◽  
Kaoru Sakatani ◽  
...  
Keyword(s):  
Healthy Aging ◽  
Near Infrared ◽  
Response Times ◽  
Cognitive Resources ◽  
Stressful Condition ◽  
Healthy Elderly ◽  
Situational Stress ◽  
Anxiety Response ◽  
Nirs Signal ◽  
Psychophysiological Correlates

Abstract. The aim of the study was to explore the effects of situational stress and anxiety in a group of healthy elderly, both in terms of psychophysiological correlates and cognitive performance. Eighteen participants ( Mage = 70 ± 6.3; range 60–85) were assessed for anxiety and were instructed to perform a computerized math task, under both a stressful and a control condition, while near-infrared spectroscopy (NIRS) signal and electrocardiography (ECG) were recorded. NIRS results evidenced an increased activation of right PFC during the entire procedure, even if effect sizes between left and right channels were larger during the experimental condition. The amount of right activation during the stressful condition was positively correlated with anxiety. Response times (RTs) were slower in more anxious than in less anxious individuals, both during the control and stressful conditions. Accuracy was lower in more anxious than in less anxious individuals, only during the stressful condition. Moreover, heart rate (HR) was not modulated by situational stress, nor by anxiety. Overall, the present study suggests that in healthy elderly, anxiety level has a significant impact on cerebral responses, and both on the amount of cognitive resources and the quality of performance in stressful situations.

Movement of Prefrontal Blood Volume during Stroop Task using Near-infrared

2016 ◽  
Vol 136 (1) ◽  
pp. 86-91
Author(s):  
Shingo Takahashi ◽  
Naoki Kodama ◽  
Naoko Kosugi ◽  
Hiroshi Takeuchi
Keyword(s):  
Blood Volume ◽  
Stroop Task ◽  
Near Infrared

Bi19S27I3 nanorods: a new candidate for photothermal therapy in the first and second biological near-infrared windows

Nanoscale ◽  
2021 ◽  
Author(s):  
Jinsong Xiong ◽  
Qinghuan Bian ◽  
Shuijin Lei ◽  
Yatian Deng ◽  
Kehan Zhao ◽  
...  
Keyword(s):  
Cancer Therapy ◽  
Photothermal Therapy ◽  
Near Infrared ◽  
Research Interest ◽  
The Past ◽  
Nir Light ◽  
Considerable Research ◽  
Key Factor

Near-infrared (NIR) light induced photothermal cancer therapy using nanomaterials as photothermal agents has attracted considerable research interest over the past few years. As the key factor in the photothermal therapy...

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