To borrow a jingle from a popular late 1980s television commercial that sought to spark the hip quotient of a respectable but fading car brand, today’s pulse oximetry devices are not your father’s pulse oximetry devices. Certainly, tomorrow’s aren’t either.
But affixing this now-trite advertising phrase to one of the first lines of offense in treating patients successfully shouldn’t detract from pulse oximetry’s legacy, nor it’s clinical importance. Instead, it underscores how much pulse oximetry devices have progressed beyond their initial function of monitoring oxygen saturation of the blood noninvasively from a single spot on the patient’s body. In fact, what started out as a simple device designed to carry out a fundamental task has evolved into more complex technology applied to various body areas and offering multiple functions at the press of a button.
Clearly, pulse oximetry devices have come a long way over the years. Among available capabilities, newer models successfully can eliminate noise that hampers accurate readings and even detect carbon monoxide levels.
Because pulse oximetry technology is moving beyond its original function it only makes sense to explore ongoing and future developments in pulse oximetry applications and capabilities, including how those developments impact overall performance. As a result, we asked key executives like Masimo Corp. CEO Joe Kiani, to briefly share their insights on what the next-generation pulse oximetry technology will look like and how its function and role in clinical, financial and operational performance will be enhanced through product development for outpatient care facilities.
OPCT: As pulse oximetry technology expands its capabilities, what do you foresee as the next big development in pulse oximetry applications, specifically as they relate to outpatient settings? Why? How do you envision these next-generation pulse oximetry devices functioning? Why do these new versions represent an advancement over current versions? What additional capabilities and features will be available to enhance patient care, particularly in the outpatient setting? If you could design and program the most futuristic pulse oximetry application (short of a “Star Trek tricorder”), what features would you include? Why do you foresee any of these features being valuable to end users? Finally, how realistic is it to expect cost-conscious outpatient care facilities to invest in these new devices?
Joe E. Kiani, founder and CEO, Masimo Corp., Irvine, CA (www.masimo.com)
Masimo introduced the first pulse oximeter capable of remaining accurate in the presence of motion and low perfusion in 1995. This advancement was based on breakthrough signal processing and sensor technology, which was a dramatic departure from how the original oximeters worked. To date, there have been over 90 independent and objective studies that prove that Masimo SET is the most accurate and reliable pulse oximeter in the world. Masimo SET literally created a new performance standard for pulse oximeters and most prudent buyers now require Masimo SET performance in any new instrument purchased.
Masimo has recently introduced the second advancement in pulse oximetry with its multi-wavelength technology, called Rainbow. Pulse oximeters have traditionally used two wavelengths of light to determine oxygen saturation. We have recently launched our Masimo Rainbow SET platform that utilizes eight wavelengths of light, which allows greater specificity in the measurement. So far, we have been able to obtain accurate measurements for two parameters, methemoglobin (SpMet), and Carboxyhemoglobin (SpCO) that have traditionally been attainable only with an invasive blood test.
Methemoglobin is an oxidized form of hemoglobin that is also incapable of carrying oxygen. Every year patients die due to elevated methemoglobin levels. Methemoglobin is a very significant issue for outpatient facilities due to the fact that methemoglobin levels are often the result of interactions with commonly used drugs including topical anesthetics such as benzocaine and lidocaine. Recently the National Academy of Clinical Biochemistry recommended that all patients receiving benzocaine during intubation and endoscopy/bronchoscopy be screened for methemoglobin.
Carboxyhemoglobin is hemoglobin bound with carbon monoxide, preventing it from being able to carry oxygen. Elevated carboxyhemoglobin is a significant risk factor for any surgical patient. In addition, patients’ carboxyhemoglobin levels can be elevated during anesthetic procedures.
Outpatient settings demand efficiency while not compromising care. Carboxyhemoglobin and methemoglobin represent significant health threats and thus need to be accounted for in any patient undergoing anesthesia. Masimo Rainbow SET Pulse CO-Oximetry represents the most efficient and effective means of measuring these parameters. The cost of the equipment is a fraction of an invasive CO-oximeter. The measurement is done noninvasively with a combo sensor that also measures oxygen saturation, pulse rate and perfusion index. These measurements are immediate and continuous.
I should also comment on one area of pulse oximetry development that isn’t so positive. Recently, forehead sensors have been marketed as another advancement. While Masimo also offers forehead sensors, we don’t exaggerate their value. Forehead sensors were first introduced almost 20 years ago. The features being marketed are faster response times and a more convenient location to place the sensor on surgical patients. And while response times are faster due to the fact that saturation changes are first seen closer to the brain, there are major limitations in the forehead as a reliable site for measurement. This is due to the fact that when patients are supine or in the Trendelberg position, venous blood tends to pool in the head and then begins to pulsate, which the pulse oximeter reads as an arterial pulse and since venous blood is at a lower saturation, the pulse oximeter will tend to read below the true arterial saturation. Multiple studies have been published over the last few years that conclude that today’s forehead sensors, like the ones introduced 20 years ago, fail on surgical patients as much as 59 percent of the time.
Pulse oximetry has gone through more technological advancement than any other vital sign over the past 10 years, first with introduction of Read-Through Motion and Low Perfusion pulse oximetry and now with the current advancements in multi-wavelength technology. I believe that SpCO and SpMet are just the beginning and over the next several years more breakthroughs in noninvasive monitoring are to come.