Cerebral Autoregulation in the Microvasculature Measured with Near-Infrared Spectroscopy

摘要: Cerebral autoregulation (CA) is the mechanism that allows brain to maintain a stable blood flow despite changes in pressure. Dynamic CA can be quantified based on continuous measurements of systemic mean arterial pressure (MAP) and global cerebral flow. Here, we show dynamic also from local are sensitive microvasculature. We used near-infrared spectroscopy (NIRS) measure temporal oxy- deoxy-hemoglobin concentrations prefrontal cortex 11 human subjects. A novel hemodynamic model translates those into volume The interplay between them described by transfer function analysis, specifically high-pass filter whose cutoff frequency describes efficiency. have pneumatic thigh cuffs induce MAP perturbation fast release during rest hyperventilation, which known enhance autoregulation. Based our model, found increased hyperventilation comparison normal breathing 10 out subjects, indicating greater shown reliably measured noninvasively microvasculature, opening up possibility localized monitoring with NIRS.