SAN FRANCISCO, Oct. 15 /PRNewswire-FirstCall/ -- Masimo, the inventor of Pulse CO-Oximetry and Read-Through Motion and Low Perfusion pulse oximetry, reported that a new independent and objective clinical study presented today at the 2007 American Society of Anesthesiologists (ASA) Meeting in San Francisco demonstrated the ability of Pleth Variability Index (PVI) to accurately and noninvasively detect changes in ventricular preload. The newest addition to the Masimo Rainbow SET technology platform, PVI is a continuous and noninvasive quantified measurement of changes in the perfusion index, capturing volume changes that may compromise cardiac function and affect systemic circulation.
The study entitled “New Algorithm for Automatic Estimation of the Respiratory Variations in the Pulse Oximeter Waveform”, was conducted at the Louis Pradel Hospital in Lyon, France, by a research team headed by Dr. Maxime Cannesson. The research team indicated that while respiratory variations in the pulse oximeter plethysmography waveform amplitude are sensitive to changes in preload and can predict fluid responsiveness in mechanically ventilated patients, they previously were not easily measured noninvasively from a bedside monitor. However, a new algorithm, PVI, available in the Masimo Rainbow SET technology platform may provide a new method for noninvasively predicting fluid responsiveness.
In this study, Dr. Cannesson and the research team tested the ability of PVI to detect changes in ventricular preload in 20 vascular surgery patients under mechanical ventilation. Mean arterial pressure (MAP) and central venous pressure (CVP) via arterial catheter and central venous catheter were recorded along with PVI at baseline and while patients were in head-down and head-up positions. Researchers stated, this study is the “first to demonstrate the ability of PVI, an index automatically derived from the pulse oximeter waveform analysis, to detect changes in ventricular preload. This new index has potential clinical applications for noninvasive hypovolemia detection and fluid responsiveness monitoring."(1)
“Fluid management optimization in mechanically ventilated patients undergoing anesthesia is of major importance since it may have clinical and economical impact,” Dr. Cannesson stated. “Indicators of response to volume expansion relying on cardio-pulmonary interactions are the best predictors of fluid responsiveness. Ideally, continuous noninvasive monitoring of these parameters would provide valuable information to clinicians in caring for mechanically ventilated patients. Masimo’s new derived index, PVI, appears to offer such a continuous, noninvasive monitor.”
Masimo PVI is a unique new measurement featured in the Masimo Rainbow SET technology platform that quantifies changes in perfusion index. PVI displays a numeric representation of the changes as a percentage on the Rainbow SET oximeter, thus allowing clinicians to track and trend these changes over time. A rising PVI may indicate developing hypovolemia (an abnormally low volume of blood circulating through the body) and a falling PVI post-fluid resuscitation is evidence of an appropriate fluid responsiveness. This trending may aid in determining appropriate intervention for patients experiencing physiologic changes in fluid volume and cardiac function, leading to better patient outcomes.
Appropriate fluid levels are vital to reducing postoperative risks and improving patient outcomes as fluid volumes that are too low (under hydration) or too high (over hydration) have been shown to decrease wound healing, increase risk of infection and cardiac complications. In extreme cases, severe hypovolemia can lead to hypovolemic shock as peripheral circulation shuts down to preserve central circulation in an attempt to maintain the heart, brain and kidney functions.
In commenting on the study, Dr. Kevin K. Tremper, Chairman of Anesthesia at University of Michigan said, “One of the biggest challenges we have in the operating room is determining whether, from a fluid volume perspective, a patient is full or empty. If PVI can help us noninvasively determine this in real time, PVI will be a huge benefit to clinicians and positively impact patient care and safety.”
Built on the “gold-standard” of Masimo SET Read-Through Motion and Low Perfusion technology, Masimo Rainbow SET is the first and only upgradeable technology platform capable of continuously and noninvasively measuring carboxyhemoglobin (SpCO) and methemoglobin (SpMet), in addition to oxyhemoglobin (SpO2), perfusion index (PI), Pleth Variability Index (PVI) and pulse rate.
About Masimo
Masimo develops innovative monitoring technologies that significantly improve patient care-helping solve “unsolvable” problems. In 1995, the company debuted Read-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 have confirmed that Masimo SET technology allows clinicians to accurately monitor blood oxygen saturation in critical care situations. Our Masimo SET platform has significantly addressed many of the previous technology limitations, has substantially contributed to improved patient outcomes and has been referred to by several industry sources as the gold standard in pulse oximetry. In 2005, Masimo introduced Masimo Rainbow SET Pulse CO-Oximetry, which, for the first time, noninvasively monitors the level of carbon monoxide and methemoglobin in the blood, 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 http://www.masimo.com.
Masimo, SET, Signal Extraction Technology, Radical, Radical-7, Rad57, APOD, and Improving Outcomes and Reducing Cost of Care by Taking Noninvasive Monitoring to New Sites and Applications are registered trademarks of Masimo Corp. ARM, Acoustic Respiratory Monitoring, BiFi, Rainbow, SpCO, SpMet, SpHb and Pulse CO-Oximeter are trademarks of Masimo Corp.
CONTACT: Tom McCall of Masimo, +1-949-297-7075
Web site: http://www.masimo.com/
