Study Shows Noninvasive SpCO(R) Helps Clinicians Detect Occult Carbon Monoxide Poisoning

December 10, 2013

IRVINE, CA -- (Marketwired) -- 12/10/13 -- Masimo (NASDAQ: MASI) announced today that a new clinical study recently published in the Emergency Medicine Journal shows that Masimo's noninvasive carboxyhemoglobin (SpCO®) from rainbow® Pulse CO-Oximetry™ helped clinicians identify 23% more patients with carbon monoxide (CO) poisoning who presented to the emergency department (ED) with headaches.1

CO poisoning is the leading cause of death resulting from accidental poisoning worldwide. Lack of timely diagnosis can delay treatment or, worse, patients discharged with an incorrect diagnosis can be re-exposed to CO. While CO poisoning happens year-round in all climates, the incidents typically increase during colder months due to the use of fossil fuel-burning heating appliances. CO poisoning accounts for an estimated 50,000 ED visits in the U.S. annually.2 Headaches are the most common symptom of CO poisoning -- others include dizziness, nausea/vomiting, confusion, fatigue, chest pain, shortness of breath, and loss of consciousness. CO poisoning often is often misdiagnosed and attributed to other illnesses such as the flu. Failure to diagnose CO poisoning can have disastrous consequences for patients and potentially other family members of affected households.3

In their prospective study patients presenting to the ED between Feb. 1 and March 31, 2011, researchers Nilay Zorbalar, Murat Yesilaras, and Ersin Aksay at Izmir Tepecik Research and Educational Hospital in Izmir, Turkey, used a Masimo Rad-57™ Pulse CO-Oximeter to noninvasively assess SpCO on 482 patients who complained of headaches.

Patients whose initial SpCO measurement was greater than 10% underwent a venous blood draw for laboratory determination of invasive carboxyhemoglobin (COHb) measurement. If a patient's invasive COHb level was greater than 10%, they were diagnosed with CO poisoning. Of the 482 patients presenting with headaches who were screened with SpCO measurement, 38 had a mean SpCO value of over 10%, 31 (6.4% of the study population) of which had elevated COHb confirmed by laboratory determination. As a screening measurement, SpCO had a positive predictive value of 82% for CO poisoning. Of the 31 true CO poisoning cases, 24 (77%) were suspected and seven (23%) were not suspected. Therefore, SpCO screening was responsible for helping the ED clinicians detect the 23% of cases that would be considered "occult," or unsuspected, CO poisoning.

The investigators concluded: "CO poisoning should be kept in mind in patients presenting to the ED with a headache. SpCO is an effective screening tool to detect CO poisoning in these patients."

1 Zorbalar N, Yesilaras M, Aksay E. "Carbon monoxide poisoning in patients presenting to the emergency department with a headache in winter months." Emerg Med J Published online ahead of print Oct. 15, 2013 Available here
2 Hampson N., Weaver L. "Carbon Monoxide Poisoning: A New Incidence for an Old Disease." Undersea Hyperb Med 2007;34:163-168. Available online here
3 Hampson N., Piantadosi C., Thom S., Weaver L. "Practice Recommendations in the Diagnosis, Management, and Prevention of Carbon Monoxide Poisoning," American Journal of Respiratory and Critical Care Medicine, Vol. 186, No. 11 (2012), pp. 1095-1101. Available online here

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

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, but not limited to: risks related to our assumptions regarding the repeatability of clinical results, risks related to our belief that Masimo SpCO will provide an accurate and effective noninvasive method of screening for CO poisoning, risks related to our belief that SpCO offers an effective front-line tool for first responders and emergency departments, 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. 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.

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, rainbow Acoustic Monitoring, RRa, Radical-7, Rad-87, Rad-57, Rad-8, Rad-5,Pulse CO-Oximetry, Pulse CO-Oximeter, Adaptive Threshold Alarm, and SEDLine are trademarks or registered trademarks of Masimo Corporation. The use of the trademarks Patient SafetyNet and PSN are under license from University HealthSystem Consortium.

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

Source: Masimo