Dynamics of Microvascular Blood Flow and Oxygenation Measured Simultaneously in Human Skin. (August 2014)

• Record Type: Journal Article
• Authors: Kuliga, Katarzyna Z.; McDonald, Erin F.; Gush, Rodney; Michel, Charles; Chipperfield, Andrew J.; Clough, Geraldine F.
• Is Part Of: Microcirculation. Volume 21:Number 6(2014:Aug.)
• Page Start: 562
• Page End: 573
• Publication Date: 2014-08
• Subjects: Biological transport -- Periodicals; Microcirculation -- Physiology -- Periodicals; 612.135
• DOI: 10.1111/micc.12136
• Languages: English
• ISSNs: 1073-9688

Abstract

<abstract abstract-type="main" id="micc12136-abs-0001"> <title>Abstract</title> <sec id="micc12136-sec-0001" sec-type="section"> <title>Objective</title> <p>To evaluate the dynamics of skin microvascular blood flow (BF) and tissue oxygenation parameters (OXY) measured simultaneously at the same site using a combined non‐invasive BF+OXY+temperature probe.</p> </sec> <sec id="micc12136-sec-0002" sec-type="section"> <title>Methods</title> <p>Skin BF, oxygenated (oxyHb) and deoxygenated (deoxyHb) haemoglobin and mean oxygen saturation (SO<sub>2</sub>) were measured in 50 healthy volunteers at rest and during perturbation of local blood flow by post‐occlusive reactive hyperaemia, sympathetic nervous system‐mediated vasoconstriction (deep inspiratory breath‐hold) and local skin warming. Signals were analysed in time and frequency domains.</p> </sec> <sec id="micc12136-sec-0003" sec-type="section"> <title>Results</title> <p>The relationship between BF and SO<sub>2</sub> over the range of flows investigated was described by a non‐linear equation with an asymptote for SO<sub>2</sub> of 84% at BF >50 PU. SO<sub>2</sub> was independently associated with BF, skin temperature, BMI and age, which together identified 59% of the variance in SO<sub>2</sub> (p<0.0001). Fourier analysis revealed periodic low frequency fluctuations in both BF and SO<sub>2</sub>, attributable to endothelial (~0.01 Hz), neurogenic (~0.04 Hz) and myogenic (~0.1Hz) flow motion activity. The frequency coherence between the BF and SO<sub>2</sub> signals was greatest in the endothelial and neurogenic frequency bands.</p> </sec> <sec id="micc12136-sec-0004" sec-type="section"> <title>Conclusions</title> <p>The simultaneous evaluation of microvascular blood flow and oxygenation kinetics in healthy skin provides a platform from which to investigate microvascular impairment in the skin and more generally the pathogenesis of microvascular disease.</p> </sec> </abstract>