Effects of rapid onset acceleration on cephalic pulsatile blood volume impedance waveforms in humans

Electrical impedance plethysmographic measurements of the relative changes in cephalic pulsatile blood volume (rheoencephalography, or REG) have been performed clinically for many years. REG indices provide information about cerebral vascular resistance (CVR). The technique has been used to noninvasively monitor real-time cephalic pulsatile blood volume changes in humans exposed to acceleration stress in the head-to-foot direction (+G/sub z/) on the Naval Air Development Center (NADC) human centrifuge. Changes in the REG waveform occurring with increasing +Gz load have been characterized.<
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