A Decrease in Spatially Resolved Near-Infrared Spectroscopy-Determined Frontal Lobe Tissue Oxygenation by Phenylephrine Reflects Reduced Skin Blood Flow

Background Peripheral arterial disease is a stenosis or occlusion of peripheral arteries that results in compromised blood flow and muscle ischemia. The available diagnostic methods are mostly used to measure and visualize blood flow and are not useful in the evaluation of perfusion, especially in diabetic patients, which is now considered to be a research priority by most of the vascular societies around the world as this is still a relatively poorly studied phenomenon. Objective The aim of this review is to explore the clinical significance of muscle tissue oxygenation monitoring in lower-extremity peripheral artery disease diagnosis using the near-infrared spectroscopy method. Methods A systematic search in PubMed, CINAHL, and Cochrane databases was performed to identify clinical near-infrared spectroscopy (NIRS) studies in English and Russian, published until September 2019, involving muscle tissue oxygenation in peripheral arterial disease (PAD). The manuscripts were reviewed by two researchers independently and scored on the quality of the research using MINORS criteria. Results After screening 443 manuscripts, 23 studies ( n = 1580) were included. NIRS-evaluated recovery time seems to be more accurate than ankle-brachial index in diabetic patients to differentiate between moderate and severe claudication. Consistent findings across all the included studies showed that both the oxygenation and deoxygenation rates as well as the recovery times varied from patient to patient and therefore were not suitable for standardization. Conclusions The clinical relevance of routine use of NIRS to diagnose PAD is unproven; therefore, its use is not currently part of standard-of-care for patients with PAD since the absolute values seem to vary significantly, depending on the outside conditions. More data need to be provided on the possible use of NIRS monitoring intraoperatively where the conditions can be more controlled.

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Tissue Oxygenation by Near-Infrared Spectroscopy and Muscle Blood Flow During Isometric Contractions of the Forearm

Canadian Journal of Applied Physiology ◽

10.1139/h99-018 ◽

1999 ◽

Vol 24 (3) ◽

pp. 216-230 ◽

Cited By ~ 38

Author(s):

Andrew Hicks ◽

Stuart Mcgill ◽

Richard L. Hughson

Keyword(s):

Blood Flow ◽

Infrared Spectroscopy ◽

Doppler Ultrasound ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Tissue Oxygenation ◽

Muscle Blood Flow ◽

Venous Blood ◽

Muscle Oxygenation ◽

Isometric Contractions

The relationship between tissue oxygenation measured by near-infrared spectroscopy (NIRS) and forearm muscle blood flow (FBF) measured by Doppler ultrasound was tested during isometric contractions at 10 and 30% maximal voluntary contraction (MVC) under conditions of normoxia and hypoxia (14% inspired O2). Six subjects maintained contractions at 10% MVCfor 5 min and at 30% for 2 min in both gas conditions. FBF was elevated during exercise at 10% MVC in hypoxia compared to normoxia, but there was no further increase in flow at 30% MVC. Median power frequency calculations from electromyographic recordings suggested progressive development of fatigue throughout both 10 and 30% MVC contractions. NIRS indicated no change in muscle oxygenation at 10% MVC, but deep venous blood O2 saturation was reduced in normoxia and more so in hypoxia. At 30% MVC, both NIRS and venous O2 saturation were reduced, with no effect of hypoxia on the NIRS signal. While NIRS might provide an indication of muscle oxygenation during isometric exercise, the conflicting findings for NIRS and direct venous blood sampling at 10 vs. 30% MVC suggest caution in the application of this noninvasive technique. Key words: exercise, Doppler ultrasound, venous blood. O2 saturation, hemoglobin

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