Measurement of muscle blood flow and O2 uptake via near-infrared spectroscopy using a novel occlusion protocol

Abstract

We describe here a novel protocol that sequentially combines venous followed by arterial occlusions to determine muscle blood flow and O2 uptake from a single measurement point using near-infrared spectroscopy (NIRS) during handgrip exercise. NIRS data were obtained from the flexor digitorum superficialis (FDS) muscle on the dominant arm of 15 young, healthy adults (3 women; 26 ± 7 years; 78.6 ± 9.1 kg). Participants completed a series of 15-s static handgrip contractions at 20, 40 and 60% of maximal voluntary contraction (MVC) immediately followed by either a: (i) venous occlusion (VO); (ii); arterial occlusion (AO); or venous then arterial occlusion (COMBO). Each condition was repeated 3 times for each exercise-intensity. The concordance correlation coefficient (CCC) and robust linear mixed effects modeling were used to determine measurement agreement between vascular occlusion conditions. FDS muscle blood flow ($${\dot{\text{Q}}}_{{{\text{FDS}}}}$$ Q ˙ FDS ) and conductance ($${\text{C}}_{{{\text{FDS}}}}$$ C FDS ) demonstrated strong absolute agreement between VO and COMBO trials from rest up to 60%MVC, as evidenced by high values for CCC (> 0.82) and a linear relationship between conditions that closely approximated the line-of-identity (perfect agreement). Conversely, although FDS muscle O2 uptake ($${{\dot {\text{V}}}}{{\text{O}}_{2{\text{FDS}}}}$$ V ˙ O 2 FDS ) displayed “substantial” to “near perfect” agreement between methods across exercise intensities (i.e., CCC > 0.80), there was a tendency for COMBO trials to underestimate $${{\dot {\text{V}}}}{{\text{O}}_{2{\text{FDS}}}}$$ V ˙ O 2 FDS by up to 7%. These findings indicate that the COMBO method provides valid estimates of $${\dot {\text{Q}}}_{{\text{FDS}}}$$ Q ˙ FDS and, to a slightly lesser extent, $${{\dot {\text{V}}}}{{\text{O}}_{2{\text{FDS}}}}$$ V ˙ O 2 FDS at rest and during static handgrip exercise up to 60%MVC. Practical implications and suggested improvements of the method are discussed.

Optoacoustic Imaging Offers New Insights into In Vivo Human Skin Vascular Physiology

“…These questions, partially explained by time-related technological limitations, motivated RH exploration with other instruments in addition to plethysmography and laser Doppler flowmetry. RH has been investigated with near-infrared spectroscopy (NIRS) [ 28 , 29 ] and compared with PAT [ 30 ], assessed with diffuse correlation spectroscopy (DCS) [ 31 ], contrast-enhanced ultrasound (CEUS) [ 32 ], and peripheral artery tonometry [ 33 ]. Although these studies confirm the possibility of the use of quantifiable metabolic and molecular variables, together with image(s), in clinical and preclinical settings, there is still no agreement about outcomes.…”

“…Stronger correlations for the “time-to-peak” variable from CEUS and NIRS were recently reported [ 32 ]. Moreover, the venous and arterial involvement in RH is still not properly controlled in typical procedures, meaning that the vascular responsiveness of both micro and macrocirculation at different depths cannot be clearly distinguished [ 17 , 28 , 29 , 34 , 35 ]. Additionally, recent data from DCS suggests that skin circulation is not the best model to study skeletal muscle vasculature by RH [ 31 ].…”

“…It is also clear that the intensity and duration of the occlusion clearly affect the procedure. The separate control of venous and arterial occlusion by using different cuff pressures offers multiple controversies [ 27 , 28 , 30 , 36 ]. We opted for the application of 200 mmHg suprasystolic pressure in our study to ensure arterial occlusion, confident that pressure affects multiple structures in depth and involves more than the microcirculatory units in the area.…”

Comparisons Between Normobaric Normoxic and Hypoxic Recovery on Post-exercise Hemodynamics After Sprint Interval Cycling in Hypoxia

“…Venous occlusion technique has been suggested to estimate O 2 supply and consumption in working muscles during exercise ( Homma et al, 1996 ). Similarly, a recent study demonstrated that combination of arterial and venous occlusion provides valid estimates of blood flow and oxygen consumption at rest and during exercise ( Dennis et al, 2021 ). Although we must acknowledge that these techniques are useful and that we should have performed this technique to obtain more insight interpretations, we considered that further arterial occlusion may not be required after exhaustion.…”

The Quantitative Associations Between Near Infrared Spectroscopic Cerebrovascular Metrics and Cerebral Blood Flow: A Scoping Review of the Human and Animal Literature

“…It is difficult to have confidence in conclusions drawn from the studies identified in this review with so few data points. It should be acknowledged that a wider body of literature that has examined the use of NIRS based methods to measure blood flow in other tissues does exist and should, to some degree, bolster confidence in the findings of the studies identified in this review (Choo et al, 2017;Bangalore-Yogananda et al, 2018;Dennis et al, 2021).…”