New Study Finds Masimo Rainbow SET Pulse CO-Oximetry(TM) Effective as a Universal Screening Tool to Identify Cases of Unsuspected CO Poisoning in ERs

March 19, 2008

Rhode Island Hospital study identifies 11 cases of unsuspected CO poisoning through universal CO screening with the Masimo Rad-57 Pulse CO-Oximeter(TM)

IRVINE, Calif., March 19 /PRNewswire-FirstCall/ -- Masimo, the inventor of Pulse CO-Oximetry and Measure-Through-Motion & Low Perfusion Pulse Oximetry, reported that a new clinical study, recently published in the Journal of Emergency Medicine, found the Masimo Rainbow SET Rad-57 Pulse CO-Oximeter to be "a safe, easily applied tool at triage that can identify cases of unsuspected elevated levels of carbon monoxide (CO) poisoning" that would otherwise have gone undetected.

Researchers at the Rhode Island Hospital, where the study was conducted, also concluded that universal SpCO(R) screening may prevent morbidity through early identification and treatment intervention, stating that: "We can point to several cases during our study period in which patient outcomes were different based upon availability of SpCO, recorded at triage."

The study titled "Noninvasive Pulse CO-Oximetry Screening in the Emergency Department Identifies Occult Carbon Monoxide Toxicity" was conducted over a nine-month period on more than 10,850 patients presenting to the Emergency Department at the Rhode Island Hospital in Providence, Rhode Island, by a research team of emergency medicine physicians from the Warren Alpert Medical School at Brown University and the Emergency Department of Rhode Island Hospital, headed by Dr. Selim Suner.

In this study, Dr. Suner, Dr. Jay, Dr. Partridge, Dr. Sucov, Dr. Valente, Dr. Chee and Dr. Hughes tested the ability to screen for CO toxicity in a busy tertiary center ED using the Masimo Rainbow SET Rad-57 Pulse CO-Oximeter and found 28 cases of CO toxicity (SpCO of > 9% for nonsmokers and >13% for smokers), of which 11 were unexpected, and were identified only with the aid of universal SpCO screening using the Masimo Rad-57. In all CO toxicity cases identified, venous or arterial COHb confirmations of elevated SpCO measurements were verified by lab analysis of blood samples taken with data results showing a "good correlation" between SpCO from the Masimo Rad-57 and COHb from the lab analysis.

The research team noted that identification of CO toxicity in the ED is often challenging because many patients may not know or suspect that they were exposed to CO and are unable to provide clinicians with sufficient history to prompt testing for carboxyhemoglobin (COHb). In addition, the symptoms of CO poisoning can be similar to the flu. However, missing the opportunity to diagnose CO poisoning at the ED because screening large populations of patients by invasive blood testing for CO toxicity is not practical and not routinely performed in the ED setting can lead to "inadvertently returning a patient to the site of CO exposure and may lead to further toxicity with the possibility of long-term neurological, psychiatric, or cardiovascular complications."

Using data extrapolated from the study at Rhode Island Hospital's level-1 trauma center ED, researchers suggest that potentially "as many as 11,000 occult poisoning cases" go undetected annually -- illustrating the significant impact that universal SpCO screening could have on public health and safety. "Screening will also protect the public by identifying hidden sources of CO in households, workplaces and schools," said researchers.

Joe E. Kiani, Chairman and CEO of Masimo, stated: "The researchers at Rhode Island Hospital have done a great public service in addressing the benefits of routine, universal screening by Pulse CO-Oximetry upon admission in emergency departments. As this study has shown, the importance of diagnosing unsuspected CO poisoning at emergency departments nationwide could mean a big difference in the lives of the estimated 11,000 people each year who may be suffering in silence as CO ravages their health."

About Masimo

Masimo (Nasdaq: MASI) develops innovative 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, and with it virtually eliminated false alarms and increased pulse oximetry's ability to detect life-threatening events. More than 100 independent and objective studies demonstrate Masimo SET provides the most trustworthy SpO2 and pulse rate measurements even under the most difficult clinical conditions, including patient motion and low peripheral perfusion. In 2005, Masimo introduced Masimo Rainbow SET, a breakthrough noninvasive blood constituent monitoring platform that can measure many blood constituents that previously required invasive procedures. Rainbow SET continuously and noninvasively measures total hemoglobin (SpHb(TM)) and oxygen content (SpOC(TM)) (pending FDA clearance), carboxyhemoglobin (SpCO(TM)), methemoglobin (SpMet(TM)), and pleth variability index (PVI(TM)), in addition to oxyhemoglobin (SpO2), perfusion index (PI) and pulse rate, allowing early detection and treatment of potentially life-threatening conditions. Founded in 1989, Masimo has the mission of "Improving Patient Outcomes 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

Forward-Looking Statements

This press release may include forward-looking statements. These forward-looking statements are based on current expectations about future events affecting us and are subject to uncertainties and factors, all of which are difficult to predict and many of which are beyond our control, including: risks related to our assumption that the Masimo Rainbow SET Rad-57 Pulse CO-Oximeter will be an effective universal screening tool at all EDs and risks related to our assumption that Masimo Pulse CO-Oximetry technology will deliver a sufficient level of clinical improvement over alternative carbon monoxide screening methods to allow for rapid adoption of the technology in hospital and emergency medicine environments, as well as other factors discussed in the "Risk Factors" section of our annual report on Form 10-K for the year ended December 29, 2007, filed with the Securities and Exchange Commission on March 4, 2008. Although we believe that the expectations reflected in our forward-looking statements are reasonable, we do not know whether our expectations will prove correct. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. We do not undertake any obligation to update, amend or clarify these forward-looking statements or the risk factors contained in our annual report on Form 10-K for the year ended December 29, 2007, whether as a result of new information, future events or otherwise, except as may be required under the federal securities laws.

Masimo, SET, Signal Extraction Technology, Improving Outcomes and Reducing Cost of Care by Taking Noninvasive Monitoring to New Sites and Applications, Rainbow, SpHb, SpOC, SpCO, SpMet, PVI, Pulse CO-Oximetry and Pulse CO-Oximeter are trademarks or registered trademarks of Masimo Corporation.

SOURCE Masimo Corporation
CONTACT: Dana Banks of Masimo Corporation, +1-949-297-7348
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