Please see Bibliography of References for a list of abstracts, manuscripts and posters.

StO₂ Proof of Concept

Reliability of near-infrared spectroscopy in people with dark skin pigmentation

Wassenaar EB, van den Brand JG. J Clin Monit Comput. 2005;19(3):195-199.

Objective: Near-infrared spectroscopy [NIRS) is a promising non-invasive technique for the continuous monitoring of tissue oxygendelivery. NIRSdetects light absorbance of haemoglobin chromophores to determine tissue oxygen saturation (StO₂).As skin colour is also determined by the presence of chromophores, it is plausible that NIRSsignal quality maybe affected by dark skin pigmentation.

Methods: Tissue saturation in the anterior compartment of the lower leg during isometric contraction was measured using NlRS in 17 volunteers with dark skin pigmentation. Measurements were continued until StO₂ was zero percent or until the signal disappeared.

ResuIts: The NIRS device failed toregister tissue saturation values at some point in nine of seventeen volunteers. This occurred more often in individuals with darker skin.

Conclusions: In patients with a dark pigmented skin. NlRSStO₂ measurements should be interpreted with caution, as melanin clearIy interferes with the quality of the reflected NIRS signal.