October 26, 2007 – Masimo reported that multiple independent and objective clinical studies and a case study were presented at the 2007 American Society of Anesthesiology (ASA) Annual Meeting in San Francisco (Oct. 13-17) focused on the benefits of Masimo's noninvasive patient monitoring.
The company said these new studies add to the more than 100 independent and objective studies demonstrating the superiority of Masimo SET pulse oximetry. Masimo said it also adds to growing research showing the efficacy of Masimo Rainbow SET in providing accurate physiological measurements of multiple blood constituents that previously required invasive procedures.
In a study entitled “New Generation and Old Generation Pulse Oximeters in Children with Cyanotic Congenital Heart Disease,” a team of anesthesiologists headed by Dr. Maxime Cannesson at the Louis Pradel Hospital in Lyon, France, found in a study of 10 children ages 7 days to 53 months following palliative cardiac surgery, Masimo obtained readings 100 percent of the time and Nellcor failed to obtain readings 15 percent of the time. Additionally, findings showed a significant difference between the Nellcor SpO2 reading and the blood gas readings, but no significant difference between the Masimo and blood gas readings when compared to laboratory CO-oximetry. For the 116 arterial samples, the accuracy of the Masimo Radical pulse oximeter was two times better than that of the Nellcor N-395 pulse oximeter.
A separate study, entitled “New Pulse Oximetry Sensors with Low Saturation Accuracy Claims - A Clinical Evaluation,” performed by Dr. Peter Cox at the Hospital for Sick Children in Toronto, Canada, compared the accuracy of the Masimo Radical with Blue Sensor, the Nellcor N-600 (with Lo-Sat) and Max-I sensor, and the Radical with LNOP sensor to laboratory CO-oximetry readings on 12 patients with congenital cyanotic cardiac lesions (CCCL). It concluded that despite advances in technology, only the Masimo Blue sensor demonstrated acceptable accuracy.
In a report entitled “Rad-57 Rainbow CO-Oximeter in Detecting Methemoglobin during Upper GI Endoscopy - A Case Report,” by Dr. Udaya B. Padakandla at Baylor University Medical Center in Dallas, Texas, the researcher described how four minutes after the Benzocaine application, the patient exhibited a rise in methemoglobin levels above 40 percent along with a decrease in SpO2 (to 90 percent), both measured continuously with the Masimo Rainbow SET Rad-57 and confirmed via arterial blood gas analysis. The patient was treated for methemoglobinemia with methylene blue and the SpO2 and methemoglobin levels returned to normal. This case report documents the induction of methemoglobinemia in a GI patient from Benzocaine spray used as a topical anesthetic prior to endoscopy and shows the accuracy and of Masimo Rainbow SET to continually and noninvasively measure methemoglobin levels during the entire procedure as confirmed by blood gas with CO-oximetry. This case illustrates the importance of continuous monitoring of SpMet when Benzocaine spray is used, the study showed.
In another study entitled “Clinical Analyses of 429 Cases of Acute CO Poisoning,” researchers from the Hyperbaric Oxygen Department of Beijing Chaoyang Hospital in Beijing, China, headed by Dr. Zhou Li, used the Masimo Rainbow SET Rad-57 Pulse CO-Oximeter and found that 98 of the 429 acute carbon monoxide (CO) poisoning patients had methemoglobin (MetHb) greater than 1.2 percent at the first measurement with significant positive correlation between CO and MetHb levels, suggesting that MetHb may be involved in the physiopathological process of hypoxia of acute CO poisoning patients. The application of Masimo Rainbow SET technology in the noninvasive measurement of carbon monoxide and methemoglobin concentration levels in the blood lead researchers to conclude that this technology “provides a noninvasive tool to greatly facilitate the clinical diagnosis and treatment for CO poisoning patients.”
In a study entitled “A Comparison of Finger, Ear and Forehead SpO2 on Detecting Oxygen Desaturation in Healthy Volunteers," by Dr. Kentaro Tokuda and researchers from the Kyushu University Hospital in Fukuoka City, Japan, researchers compared the time for desaturations and resaturations to be detected by Nellcor forehead (MaxFast), Masimo ear (TC-I) and finger (LNOP) SpO2 sensors when patients were in heads-down, supine and heads-up positions. The study found Masimo's ear sensor to be as fast, or slightly faster, than the Nellcor forehead sensor in detecting desaturations and resaturations. The researchers concluded "sensors on the head (forehead and ear), especially Masimo ear sensor, can detect hypoxia as soon as or even sooner than finger,” adding that “sensors on the head (forehead and ear) can also sense recovery state from hypoxia sooner than finger.”
In addition, a study entitled “New Algorithm for Automatic Estimation of the Respiratory Variations in the Pulse Oximeter Waveform” conducted at the Louis Pradel Hospital in Lyon, France by a team headed by Dr. Maxime Cannesson, demonstrated the ability of Pleth Variability Index (PVI) to accurately and noninvasively detect changes in patient fluid volume. Researchers noted that PVI “has potential clinical applications for noninvasive hypovolemia detection and fluid responsiveness monitoring.”
For more information: www.masimo.com