Measurement of hemodynamics during postural changes using a new wearable cephalic laser blood flowmeter.
BACKGROUND
Patients with orthostatic hypotension have pathologic hemodynamics related to changes in body posture. A new cephalic laser blood flowmeter that can be worn on the tragus to investigate the hemodynamics upon rising from a sitting or squatting posture was developed.


RESULTS
The relationship between cephalic hemodynamics and cerebral ischemic symptoms in 63 subjects in a sitting, squatting, and standing positions using the new device was evaluated. Transient decrease in blood pressure within 15 s after rising to an erect position possibly causes dizziness, syncope, and fall. Subjects exhibiting dizziness upon standing showed a significant decrease in the cephalic blood flow (CBF) and indirect beat-to-beat systolic blood pressure, as monitored by the Finometer, and a significant correlation was observed between the drop ratio (drop value on rising/mean value in the squatting position) of CBF and that of systolic blood pressure.


CONCLUSIONS
This new wearable CBF-meter is potentially useful for estimating cephalic hemodynamics and objectively diagnosing cerebral ischemic symptoms of subjects in a standing posture.
Fujikawa
Tetsuya
T
Department of Medical Science and Cardiorenal Medicine, Yokohama City University Graduate School of Medicine, Japan. t066033c@yokohama-cu.ac.jp
Tochikubo
Osamu
O
Kura
Naoki
N
Kiyokura
Takanori
T
Shimada
Junichi
J
Umemura
Satoshi
S
D000328:Adult; D001783:Blood Flow Velocity; D001794:Blood Pressure; D002545:Brain Ischemia / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D002560:Cerebrovascular Circulation; D004431:Ear, External; D004867:Equipment Design; D005260:Female; D006339:Heart Rate; D006439:Hemodynamics; D006801:Humans; D007024:Hypotension, Orthostatic / Q000209:etiology / Q000503:physiopathology*; D017078:Laser-Doppler Flowmetry / Q000295:instrumentation*; D008297:Male; D011187:Posture; D055815:Young Adult