Masimo, the inventor of Pulse CO-Oximetry and Measure-Through Motion and Low Perfusion pulse oximetry, has reported that a new clinical study showed that Masimo PVI successfully predicts the hemodynamic effects of Positive End-Expiratory Pressure (PEEP) in mechanically ventilated patients after cardiac surgery.
According to study researchers, the ability of PVI to predict the effects of PEEP may allow physicians to ‘optimize the respiratory uptake in oxygen and its delivery to the tissues.’ It is critically important for clinicians to accurately determine whether the addition of PEEP, a ventilator setting that can alter cardiac output (the amount of blood the heart pumps), will have positive or negative hemodynamic effects.
PEEP can be beneficial if it improves PaO2 (arterial oxygenation and oxygen delivery during anesthesia) by opening collapsed alveoli to increase gas exchange, but harmful if it decreases blood flow to the tissues (most often measured as cardiac output).
Masimo PVI has been shown on multiple clinical studies to continuously and noninvasively predict fluid responsiveness in mechanically-ventilated patients under general anesthesia. However, researchers in the study approached the relationship between PVI and fluid responsiveness in the reverse manner from which it is usually evaluated. Instead of looking at whether PVI predicts a positive response by the patient, they evaluated whether PVI predicated a negative response (decreased preload) with the addition of PEEP.
Researchers from the Louis Pradel Hospital, department of anesthesiology and intensive Care, in Lyon, France, and the University of California, Irvine, School of Medicine in Irvine, California, studied 21 mechanically-ventilated and sedated patients in the postoperative period after coronary artery bypass graft (CABG) surgery.
Researchers have concluded from the study that Masimo PVI may be ‘useful in automatically and noninvasively detecting the hemodynamic effects of PEEP when VT is > 8 mL/kg in ventilated and sedated patients with acceptable sensitivity and specificity.’
Masimo said that the current study reinforces the value of PVI compared to invasive measures and highlights PVI’s value for reliably detecting the hemodynamic effects of PEEP and predicting hemodynamic instability.
PVI is available as part of Masimo Rainbow SET Pulse CO-Oximetry a breakthrough noninvasive blood constituent monitoring platform capable of measuring multiple blood constituents that previously required invasive procedures, including: total hemoglobin (SpHb), oxygen content (SpOC), carboxyhemoglobin (SpCO), methemoglobin (SpMet), and PVI, in addition to oxyhemoglobin (SpO2), pulse rate (PR), and perfusion index (PI).