Masimo Corporation (NASDAQ: MASI) announced that multiple new clinical research studies presented this week at the European Society of Anaesthesiology (ESA) Annual Congress in Amsterdam add to the growing body of evidence that Masimo noninvasive and continuous total hemoglobin (SpHb®) and Pleth Variability Index (PVI®) are accurate and useful noninvasive and continuous measurements in a variety of patients.

Two studies, from researchers in Japan and Sweden, evaluated the accuracy and reliability of SpHb in both surgical and ED patients and found clinically acceptable correlations between noninvasive SpHb measurements and invasive lab values. Researchers at the Hamamatsu University School of Medicine in Japan analyzed 89 hemoglobin samples from 16 surgical patients and found a correlation coefficient between SpHb (obtained using the Masimo Radical-7 and R-125 rev C sensor) and invasive lab values of 0.8 with a bias of 0.65 g/dL and precision of 1.1 g/dL. Citing this as the first introduction of SpHb to Japanese patients, researchers concluded that "SpHb is reliable on Japanese patients."(1) Similarly, researchers at the Karolinska Institute in Stockholm, Sweden, compared SpHb measurements (obtained using the Masimo Radical-7 software version and adult ReSposable sensor rev E) to invasive venous blood sampling (tHb) in 30 patients admitted to the emergency room and found a very low bias of -0.2 and standard deviation of 1g/dL, with limits of agreement of -2.2 to 1.8 g/dL. Citing "fairly good agreement between tHb and SpHb values across the entire measurement range," researchers concluded that "SpHb monitoring provides hemoglobin values with good agreement to laboratory analysis of blood."(2)

Two other studies, conducted in France and Japan, analyzed finger, ear, and forehead sites for PVI measurement and found that sites on the head enable the best measurement. Previous studies have shown that PVI, as measured at the finger site, can help clinicians assess fluid responsiveness and improve fluid management to decrease patient risk. Results showed that Masimo ear and forehead sensors provide the best accuracy for PVI measurement. At the Louis Pradel Hospital in France, researchers evaluated PVI measurements obtained from the ear, forehead, and finger (using the Masimo Radical-7 and LNOP Adt sensor) in 16 patients during ongoing surgery and found that PVI correlations to pulse pressure variations (PPV) were r=0.72 at the ear, r=0.60 at the forehead, and r=0.43 at the finger (all p<0.001). PVI forehead >14% and PVI ear >15% predicted a PPV > 10% with 73% sensitivity and 72% specificity, while PVI finger > 13% predicted a PPV > 10% with a sensitivity of 78% and a specificity of 44% -- leading researchers to conclude that "ear and forehead provide best accuracy for PVI."(3) In Japan, researchers at Kagoshima University tested the effects of surgical stimuli on PVI measurements at the finger and forehead (obtained using the Masimo Radical-7 software version 7.3.11 and LNOP Adt sensor) in nine mechanically ventilated surgical patients and found that forehead PVI & perfusion index (PI) remained stable before and after skin incision while PVI captured at the finger site were more sensitive to vasomotor tone. Researchers concluded that "PVI obtained from the forehead may be a more reliable predictor of fluid responsiveness under conditions of varying vasomotor tone."(4)

SpHb and PVI are available as part of Masimo rainbow SET® platform -- the first-and-only technology to noninvasively and continuously measure total hemoglobin (SpHb®), oxygen content (SpOC™), carboxyhemoglobin (SpCO®), methemoglobin (SpMet®), Pleth Variability Index (PVI®), perfusion index (PI), and acoustic respiration rate (RRa™), in addition to the 'gold standard' Measure-Through Motion and Low Perfusion performance of Masimo SET® oxyhemoglobin (SpO2), and pulse rate (PR).

(1) Ishida C, Shiraishi Y., Mimuro S., Yu S., Katoh T., Sato S.. "Accuracy of a Noninvasive Measurement of Hemoglobin Via Pulse CO-Oximetry in Japanese Population." Hamamatsu University School of Medicine, Department of Anesthesiology and Intensive Care, Hamamatsu, Japan.

(2) Svensen C.H., Rodhe P., Lundstrom N., Berglund E., Sjostrand F. "Use of a Noninvasive Hemoglobin Monitor for Volume Kinetic Analysis in an Emergency Room Setting." Karolinska Institute,/Department of Clinical Science and Education, Department of Anesthesiology and Intensive Care, Stockholm, Sweden.

(3) Pavlakovitch I., Desebbe O., Cannesson M., Bastien O., Lehot J.J. "What is the Best Site for Measuring the Pleth Variability Index (PVI) During a Surgery Procedure?" Hospices Civils de Lyon Hopital L Pradel, Department of Anesthesiology and Intensive Care, Bron-Lyon, France.

(4) Matsunaga A., Kakihan Y., Kuniyoshi T., Kumemura M. Uchida Y., Kanmura Y. "Difference Between Pleth Variability Index Obtained from the Finger and Forehead." Kagoshima University, Department of Anesthesiology, Kagoshima, Japan.

Source: Masimo Corporation