New Clinical Study Presented at the International Anesthesia Research Society's Annual Meeting Shows Benefit of Masimo's Oxygen Reserve Index, ORI

March 30, 2015

IRVINE, CA -- (Marketwired) -- 03/30/15 -- Masimo (NASDAQ: MASI) announced today that a new clinical study presented at the International Anesthesia Research Society's 2015 Annual Meeting showed that Masimo's latest noninvasive patient monitoring parameter, Oxygen Reserve Index™ or ORI™, could help clinicians in the early detection of an impending desaturation in patients receiving supplemental oxygen.1

Pulse oximetry (SpO2) provides noninvasive and continuous visibility to arterial blood oxygenation in hypoxia and normoxia (normal oxygenation). Clinicians often use arterial oxygen partial pressure (PaO2), which can be intermittent and delayed, to monitor levels of hyperoxia (higher than normal oxygenation). Between invasive sampling, changes in PaO2 can be difficult to assess, and therefore hypoxia or hyperoxia can occur unexpectedly.

ORI, Masimo's 11th rainbow® parameter2, is a relative index of the partial pressure of oxygen in arterial blood (PaO2) in the range of 100 to 200 mmHg. ORI is intended to supplement, not replace, SpO2 monitoring and PaO2 measurements.

In the retrospective study conducted at Loma Linda University School of Medicine in Loma Linda, Calif., Dr. Richard Applegate, M.D., and colleagues evaluated the relationship between ORI and PaO2 of 103 patients who underwent surgery in which arterial catheterization was planned.

Researchers included for analysis 1,540 ORI samples using a Masimo Radical-7® Pulse CO-Oximeter®. Regression analysis was used to compare PaO2 from clinically indicated arterial blood gas samples to ORI and calculated changes in ORI (ΔORI) to calculated changes in PaO2 (ΔPaO2).

During a total of 2,377 monitored hours, researchers found that ORI could be calculated about 91.5% of that time, and indicated that ORI was a noninvasive method for measuring moderate hyperoxia (PaO2 was ≥ 150 mmHg in 96.5% of ORI > 0.54, while PaO2 was > 100 mmHg for all ORI > 0.24).

Investigators noted; "An ORI decrease to near 0.24 may provide early warning of declining PaO2 approaching 100 mmHg," such as during procedures that mandate apnea or one lung ventilation; during difficult intubation; trauma patients with pulmonary contusion or massive resuscitation, and that "the ability to detect PaO2 ≥ 150 mmHg by ORI > 0.54 may prove useful for titrating (fraction of inspired oxygen) FiO2."

Researchers concluded: "For intraoperative PaO2 between 240 and 100 mmHg, decrease in ORI appears to provide a clinically useful indication of falling PaO2 before desaturation," and further stated, "Use of this technology could allow for early detection of impending hypoxia in the critical care setting, particularly in patients with congestive heart failure, which would lead to more rapid treatment and possibly mitigate the need for intubation and mechanical ventilation."

Radical-7® with Root has a CE Mark with the ORI parameter and is not FDA cleared and is not available for sale in the United States.

1. Applegate R, Dorotta I, Applegate P, Andrews G, Olson M, Um M. "Relationship Between Oxygen Reserve Index and Arterial Partial Pressure of Oxygen During Surgery." Proceedings of the International Anesthesia Research Society's 2015 Annual Meeting, March 23, Honolulu, Hawaii, PR03-56-Technology, Computing and Simulation, Equipment Monitoring 5, Coral Ballroom, S-377.
2. 11 parameters include: 1) oxygen saturation (SpO2); 2) Pulse rate; 3) Perfusion index (PI); 4) Pleth Variability Index (PVI); 5) Respiration Rate from the pleth (RRp); 6) Total hemoglobin (SpHb); 7) Oxygen Content (SpOC); 8) Carboxyhemoglobin (SpCO); 9) Methemoglobin (SpMet); 10) Fractional oxygen saturation (SpfO2); 11) Oxygen Reserve Index (ORI)

About Masimo
Masimo (NASDAQ: MASI) is the global leader in innovative noninvasive monitoring technologies that significantly improve patient care -- helping solve "unsolvable" problems. In 1995, the company debuted Measure-Through Motion and Low Perfusion pulse oximetry, known as Masimo SET®, which virtually eliminated false alarms and increased pulse oximetry's ability to help clinicians detect life-threatening events. More than 100 independent and objective studies have shown that Masimo SET® outperforms other pulse oximetry technologies, even under the most challenging clinical conditions, including patient motion and low peripheral perfusion. In 2005, Masimo introduced rainbow ® Pulse CO-Oximetry™ technology, allowing noninvasive and continuous monitoring of blood constituents that previously required invasive procedures; total hemoglobin (SpHb®), oxygen content (SpOC), carboxyhemoglobin (SpCO®), methemoglobin (SpMet®), PVI®, and perfusion index (PI), in addition to measure-through motion SpO2, and pulse rate. In 2008, Masimo introduced Patient SafetyNet™, a remote monitoring and wireless clinician notification system designed to help hospitals avoid preventable deaths and injuries associated with failure to rescue events. In 2009, Masimo introduced rainbow® Acoustic Monitoring, the first-ever commercially available noninvasive and continuous monitoring of acoustic respiration rate (RRa™). Masimo SET® and Masimo rainbow® technologies also can be found in over 100 multiparameter patient monitors from over 50 medical device manufacturers around the world. Founded in 1989, Masimo has the mission of "Improving Patient Outcome and Reducing Cost of Care ... by Taking Noninvasive Monitoring to New Sites and Applications®." Additional information about Masimo and its products may be found at @masimoinnovates

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 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 risks related to our assumptions regarding the repeatability of clinical results, risks related to our assumptions that Masimo ORI offers noninvasive, continuous patient monitoring enabling full-time visibility to dissolved arterial oxygen status that may enable proactive interventions in all patients, 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 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.

Masimo, SET, Signal Extraction Technology, Improving Patient Outcome and Reducing Cost of Care... by Taking Noninvasive Monitoring to New Sites and Applications, rainbow, SpHb, SpOC, SpCO, SpMet, PVI are trademarks or registered trademarks of Masimo.

Media Contact:
Mike Drummond
Masimo Corporation
(949) 297-7434

Source: Masimo