New Study Evaluates the Ability of Masimo ORi™ to Reflect Oxygenation During Moderate Hyperoxia

NEUCHATEL, Switzerland--(BUSINESS WIRE)--Masimo (NASDAQ: MASI) announced today the findings of a study recently published in Anesthesia & Analgesia in which researchers at the University of Groningen, the Netherlands, and Ghent University, Belgium, investigated the ability of Masimo ORi™ (Oxygen Reserve Index) to show trends in oxygenation in the moderate hyperoxic region (partial pressure of oxygen in arterial blood [PaO₂] in the range of 100 to 200 mmHg).¹ ORi is available outside the U.S. and is intended as a noninvasive, relative indicator of a patient’s oxygen reserve during moderate hyperoxia. ORi can be trended and has optional alarms to notify clinicians of changes in oxygenation.

Noting that monitoring oxygenation using pulse oximetry alone “gives little information on PaO₂” during conditions of normoxia and hyperoxia, Dr. Jaap Jan Vos and colleagues sought to evaluate the correlation of ORi to PaO₂ during moderate hyperoxia. They collected data from 20 healthy adult volunteers, who breathed a series of standardized oxygen concentrations ranging from mildly hypoxic (inspired oxygen = 14%) to extremely hyperoxic (inspired oxygen = 100%). ORi and SpO₂ were noninvasively and continuously measured by sensors on both the second and fourth fingers and displayed on a Masimo Radical-7^® Pulse CO-Oximeter^®. At baseline and at each induced oxygenation stage, arterial blood samples were taken for blood gas analysis and PaO₂ was measured invasively using a Siemens Rapidpoint 405 CO-Oximeter.

The researchers collected 1,090 paired data points of simultaneous ORi and PaO₂ values. In the “ORi-sensitive” range of 100-200 mmHg, the mean ORi value was 0.16, with associated oxygen saturation (SpO₂) values of ≥ 97% at all points. Correlation between ORi and PaO₂ was positive at all points (p < 0.0001), with R values of 0.78, 0.83, and 0.84 for sensor 1, sensor 2, and mean of both sensors, respectively. To assess ORi’s trending ability, the researchers used a 4-quadrant plot and calculated that ORi trending of PaO₂ within the range of 100-200 mmHg had a concordance rate of 94%.

The researchers concluded, “In this prospective volunteer validation study, a strong and positive correlation between PaO₂ and ORi was found, together with a good trending ability. Based on these data, the future use of ORi as a continuous noninvasive monitoring tool for assessing oxygenation status in patients receiving supplemental oxygen might be supported.” They also noted that “in healthy volunteers, ORi provides reasonable trending information of PaO₂ around the moderate hyperoxic range of PaO₂ for which its use is intended. Also, changes in PaO₂ are well reflected by changes in ORi, with good concordance. The trend in ORi can be used to track changes in PaO₂ levels in the moderate hyperoxic region, and absolute values should not be interpreted for PaO₂ levels.”

The researchers noted several limitations of the study, including that “additional studies are required to confirm these findings in a clinical setting” and that the influence of factors such as patient comorbidity and clinical circumstances requires further research. In addition, the researchers observed differences between the absolute values of simultaneously measured ORi values from sensors placed at different sites on the subject, which may require further studies in order to clinically rely on absolute ORi values as a direct measure of oxygen reserve, especially in situations where accurate oxygenation assessment may be necessary.

Study co-author Professor Thomas Scheeren commented, “ORi fills a gap in the monitoring of patients receiving supplemental oxygen by noninvasively and continuously trending the course of arterial oxygen tension. It may help to better titrate oxygen therapy to avoid both hypoxia and unintended hyperoxia.”

ORi has not received FDA 510(k) clearance and is not available for sale in the United States.

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Reference

1. Vos JJ, Willems CH, Van Amsterdam K, van den Berg J, Spanjersberg R, Struys MMRF, and Scheeren TW. Oxygen Reserve Index: Validation of a New Variable. Anesth Analg. 22 Aug 2018. DOI: 10.1213/ANE.0000000000003706.

About Masimo

Masimo (NASDAQ: MASI) is a global leader in innovative noninvasive monitoring technologies. Our mission is to improve patient outcomes and reduce the cost of care. In 1995, the company debuted Masimo SET^® Measure-through Motion and Low Perfusion™ pulse oximetry, which has been shown in multiple studies to significantly reduce false alarms and accurately monitor for true alarms. Masimo SET^® has also been shown to help clinicians reduce severe retinopathy of prematurity in neonates,¹ improve CCHD screening in newborns,² and, when used for continuous monitoring with Masimo Patient SafetyNet™ in post-surgical wards, reduce rapid response activations and costs.^3,4,5 Masimo SET^® is estimated to be used on more than 100 million patients in leading hospitals and other healthcare settings around the world,⁶ and is the primary pulse oximetry at 9 of the top 10 hospitals listed in the 2018-19 U.S. News and World Report Best Hospitals Honor Roll.⁷ In 2005, Masimo introduced rainbow^® Pulse CO-Oximetry technology, allowing noninvasive and continuous monitoring of blood constituents that previously could only be measured invasively, including total hemoglobin (SpHb^®), oxygen content (SpOC™), carboxyhemoglobin (SpCO^®), methemoglobin (SpMet^®), Pleth Variability Index (PVi^®), and more recently, Oxygen Reserve Index (ORi™), in addition to SpO₂, pulse rate, and perfusion index (Pi). In 2014, Masimo introduced Root^®, an intuitive patient monitoring and connectivity platform with the Masimo Open Connect^® (MOC-9^®) interface, enabling other companies to augment Root with new features and measurement capabilities. Masimo is also taking an active leadership role in mHealth with products such as the Radius-7^® wearable patient monitor, iSpO₂^® pulse oximeter for smartphones, and the MightySat™ fingertip pulse oximeter. Additional information about Masimo and its products may be found at www.masimo.com. Published clinical studies on Masimo products can be found at http://www.masimo.com/evidence/featured-studies/feature/.

ORi has not received FDA 510(k) clearance and is not available for sale in the United States.

The use of the trademark Patient SafetyNet is under license from University HealthSystem Consortium.

References

1. Castillo A et al. Prevention of Retinopathy of Prematurity in Preterm Infants through Changes in Clinical Practice and SpO₂ Technology. Acta Paediatr. 2011 Feb;100(2):188-92.
2. de-Wahl Granelli A et al. Impact of pulse oximetry screening on the detection of duct dependent congenital heart disease: a Swedish prospective screening study in 39,821 newborns. BMJ. 2009;Jan 8;338.
3. Taenzer AH et al. Impact of Pulse Oximetry Surveillance on Rescue Events and Intensive Care Unit Transfers: A Before-And-After Concurrence Study. Anesthesiology. 2010; 112(2):282-287.
4. Taenzer AH et al. Postoperative Monitoring – The Dartmouth Experience. Anesthesia Patient Safety Foundation Newsletter. Spring-Summer 2012.
5. McGrath SP et al. Surveillance Monitoring Management for General Care Units: Strategy, Design, and Implementation. The Joint Commission Journal on Quality and Patient Safety. 2016 Jul;42(7):293-302.
6. Estimate: Masimo data on file.
7. http://health.usnews.com/health-care/best-hospitals/articles/best-hospitals-honor-roll-and-overview.

Forward-Looking Statements

This press release includes forward-looking statements as defined in Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, in connection with the Private Securities Litigation Reform Act of 1995. These forward-looking statements include, among others, statements regarding the potential effectiveness of Masimo ORi™. These forward-looking statements are based on current expectations about future events affecting us and are subject to risks and uncertainties, all of which are difficult to predict and many of which are beyond our control and could cause our actual results to differ materially and adversely from those expressed in our forward-looking statements as a result of various risk factors, including, but not limited to: risks related to our assumptions regarding the repeatability of clinical results; risks related to our belief that Masimo's unique noninvasive measurement technologies, including Masimo ORi, contribute to positive clinical outcomes and patient safety; risks related to our belief that Masimo noninvasive medical breakthroughs provide cost-effective solutions and unique advantages; as well as other factors discussed in the "Risk Factors" section of our most recent reports filed with the Securities and Exchange Commission ("SEC"), which may be obtained for free at the SEC's website at www.sec.gov. Although we believe that the expectations reflected in our forward-looking statements are reasonable, we do not know whether our expectations will prove correct. All forward-looking statements included in this press release are expressly qualified in their entirety by the foregoing cautionary statements. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of today's date. We do not undertake any obligation to update, amend or clarify these statements or the "Risk Factors" contained in our most recent reports filed with the SEC, whether as a result of new information, future events or otherwise, except as may be required under the applicable securities laws.