Neonatal Oximeter Bias Study

The accuracy of clinical pulse oximeters is specified as 3% RMS (root mean squared of the bias and variance) compared to arterial SaO2, in the range of 70-100% SpO2. This combines errors from bias and from scatter (imprecision). These validations are carried out under ideal laboratory conditions; that is, on healthy volunteers who undergo experimental desaturations, and not in the routine clinical environment. In a large multicenter clinical observation study, Ross et al in 2013 identified important related concerns. Specifically, they found that many of the clinical measurements were outside the 3% accuracy envelop. Specifically, they reported that bias varied depending on the level of saturation, the oximeter brand, sensor, race and site perfusion. Others have identified relevant differences in oximeters, oximeter sensors \[Maiwald\], and skin pigmentation.

Our study would be the first study in the neonatal ICU evaluating bias to consider different oximeters, sensors and sensor sites. It is highly topical in that changes in average SpO2 of 3% have been associated with excess neonatal mortality and morbidity.

This study is planned to investigate the source and magnitude of differences in SpO2 readings from oximeter sensors at different sensor sites that are routinely noticed by clinicians. While these differences are most often ignored and attributed to sensor site perfusion, if systematic they could have marked impact on mortality and morbidity.

The aim of the investigation is to provide practical guidance relating to SpO2 bias among oximeters, oximeter sensors and sensor location. While taking advantage of the clinical need for 2 oximeter sensors, the results will be applicable to all neonatal oximeter monitoring.

An observational design was selected to take place in centers using automated FiO2 control systems (A-FiO2) that routinely require the use of one sensor for control and another for monitoring. This is a refinement of the approach used in the often-cited multicenter evaluation of neonatal SpO2 exposure. Thus, without an investigational intervention the observational design is well suited to collect comparable data from multiple centers.

• Bias between paired SpO2 related to site [Срок оценки: 1 month (250 observations is expected from each participating center; on average 2 patients and 5 observations per day per patient assumed)]
• Bias between paired SpO2 related to sensor location [Срок оценки: 1 month (250 observations is expected from each participating center; on average 2 patients and 5 observations per day per patient assumed)]
• Bias between paired SpO2 related to oximeter brand pairs [Срок оценки: 1 month (250 observations is expected from each participating center; on average 2 patients and 5 observations per day per patient assumed)]
• Bias between paired SpO2 related to sensor pairs [Срок оценки: 1 month (250 observations is expected from each participating center; on average 2 patients and 5 observations per day per patient assumed)]
• Bias between paired SpO2 related to oximeter averaging setting [Срок оценки: 1 month (250 observations is expected from each participating center; on average 2 patients and 5 observations per day per patient assumed)]
• Bias between paired SpO2 related to skin shade [Срок оценки: 1 month (250 observations is expected from each participating center; on average 2 patients and 5 observations per day per patient assumed)]