The influence of larger subcutaneous blood vessels on pulse oximetry.

Objective: Recent studies have renewed interest in reflectance pulse oximetry, specifically for monitoring the patient's forehead. Blood circulation on the forehead immediately above the eyebrow is fed by arteries that branch from the internal carotid artery and lack the vasoconstrictor response present in more peripheral regions. Some investigators question, however, the reliability of monitoring SpO2 on the forehead due to prior reported inaccurate readings with reflectance sensors.

The effects of motion artifact and low perfusion on the performance of a new generation of pulse oximeters in volunteers undergoing hypoxemia.

Introduction: Motion artifact and low perfusion often lead to faulty or absent pulse oximetry readings in clinical practice.

Objective: Determine the impact of motion artifact and low perfusion on newly introduced pulse oximetry technologies during hypoxemic episodes in healthy volunteers.

Methods: Five different pulse oximeters from 4 manufacturers (the Datex Ohmeda 3900P; the Agilent; the Nellcor N-3000; the Nellcor N-395; and the Schiller OX-1, which is the European version of the Ivy SatGuard 2000 with Masimo SET) were compared with respect to their ability (separated or in combination) to provide accurate readings in the presence of motion artifact and low perfusion.