The measurement of oxygen levels in the blood commonly referred to as blood oxygen saturation (SpO2) is a critical medical diagnostic. The condition of below normal levels (<95%) is termed hypoxemia and is associated with patients who have asthma, heart disease, and chronic obstructive pulmonary disease … SpO2 levels are also of interest for brain and other surgical procedures (i.e. flap surgery), peripheral vascular disease (PVD), tumor development, the healing of wounds from conditions such as diabetic foot ulcer, systemic rheumatic disease, neuropathy and sepsis2–5. Pulse oximeters, a simple optical device that measures the ratios of two critical band-passes of light through an appendage … read more