The device is a non invasive NIRS monitor. It detects signals from which are derived venous and arterial blood brain oxygen levels.~The device will be used as a adjunct monitor in patients with a brain injury or at risk of a brain injury.~The primary objective of the study is to measure the absolute and relative accuracy of the StO2 device by comparing the NIRS-derived brain tissue oxygen saturation with blood-referenced CO-oximeter oxygen saturation values. The CO-oximeter oxygen saturation values from paired arterial and internal jugular venous blood gas samples are then inserted into a weighted-equation to derive the calculated brain tissue oxygen saturation. Accuracy is reported over a range of oxygen saturations with study subjects exposed to a controlled oxygen desaturation with serial sampling of paired arterial and internal jugular venous blood gas samples.
The purpose of the study is to calibrate and to validate the accuracy of the oximeter with an estimate of brain oxygen levels assessed by measuring arterial and internal jugular vein blood oxygen saturations.