Effect of body position on NIRS based hemodynamic measures from prefrontal cortex

Abstract

This study focuses on the positional effects on hemodynamic changes monitored by the functional near infrared (fNIR) spectroscopy. The motivation behind this exploratory study is to provide a standard approach for a number of bedside, and postural applications where the body-head position can influence the fNIR signal readings. By administering two consecutive experimental protocols, we investigated effects of the potential body-head positions that may be the cases during sleep and anesthesia recordings. Furthermore dynamic tilting was used to address positional effects from lying to standing up. Positions of supine and tilted are significantly different for HbO 2 and Hb (p < .05). The natural positions, i.e., sitting, prone, supine, and sideways showed differentiations in the fNIR measures. The deoxygenated hemoglobin values seem to be the least effected component of fNIR recordings across all different positions. © 2012 Springer-Verlag.