New Study Finds That Use of Masimo SedLine® PSi and DSA May Significantly Reduce Postoperative Delirium

NEUCHATEL, Switzerland–(BUSINESS WIRE)–Masimo (NASDAQ: MASI) today announced the findings of a prospective study published in Frontiers in Neurology in which Dr. Na Xu and colleagues at Capital Medical University in Beijing investigated whether general anesthesia guided by Masimo SedLine^® Brain Function Monitoring parameters on Root^® could reduce the incidence of postoperative delirium (POD) in patients undergoing carotid endarterectomy (CEA). Using a combination of SedLine’s Patient State Index (PSi), an index based on processed electroencephalogram (EEG), and the Density Spectral Array (DSA), which represents the power of the EEG on both sides of the brain, to guide anesthesia during the procedure, the researchers found a significantly reduced risk of postoperative delirium, and concluded that patients “may benefit from the monitoring of multiple EEG parameters during surgery.”¹

The researchers noted that cerebral blood supply may be “severely disrupted” during CEA, the gold standard treatment for severe carotid stenosis, and that cerebral function is “highly vulnerable” to even brief changes in oxygen and blood supply, as well as to cerebral vascular diseases like carotid stenosis. POD is a “common yet serious” type of geriatric neurological dysfunction associated with worse short- and long-term prognosis and higher healthcare costs. Noting that the incidence of POD is associated with the duration of EEG suppression during surgery, they sought to investigate whether monitoring multiple processed EEG parameters simultaneously to guide anesthesia during a procedure like CEA could positively impact the incidence of POD, compared to use of a single parameter alone.

The authors enrolled 255 patients scheduled for CEA and divided them randomly into an intervention group (n=127, mean age 62) and a standard group (n=128, mean age 63). In the intervention group, general anesthesia was managed using a combination of Masimo SedLine PSi and DSA monitoring (designed to reduce the risk of intraoperative EEG burst suppression); in the standard group, PSi without DSA monitoring was used. In both groups, patients were also monitored with continuous transcranial Doppler ultrasound and near-infrared spectroscopy (NIRS) (designed to avoid perioperative cerebral hypoperfusion or hyperperfusion). The primary outcome was the incidence of POD, measured using the Confusion Assessment Method, during the first three days after surgery. Secondary outcomes were postoperative hospital length of stay (LOS) and other neurologic complications. A team of neurophysiologists independently reviewed the EEG data acquired by SedLine to calculate the cumulative duration of burst suppression for each patient.

The researchers found that the incidence of POD was significantly lower in the intervention group (7.87% of patients) compared to the standard group (28.91% of patients, p < 0.01). Patients in the intervention group also spent significantly less overall time with EEG suppression. There was no significant difference in the incidence of other neurologic complications.

The researchers concluded, “Processed electroencephalogram-guided general anesthesia management, consisting of PSi combined with DSA monitoring, can significantly reduce the risk of postoperative delirium in patients undergoing CEA. Patients, especially those exhibiting hemodynamic fluctuations or receiving surgical procedures that disrupt cerebral perfusion, may benefit from the monitoring of multiple EEG parameters during surgery.”

Postoperative delirium is an acute state of mental confusion characterized by alterations in attention, consciousness, and disorganized thinking. A common and serious complication, POD afflicts up to 60% of patients after major surgery,^2-5 is most common in the elderly,^2-5 and occurs in up to 91% of the critically ill.⁶ POD is associated both with worse short- and long-term outcomes and higher costs,^3,6-9 and numerous medical bodies—including the American Society of Anesthesiologists (ASA), the United Kingdom National Institute for Health and Care Excellence, the American Geriatric Society, and the American College of Surgeons—have made the prevention of POD a public health priority.^10-13 The ASA’s Brain Health Initiative, dedicated to minimizing the impact of pre-existing cognitive deficits and optimizing the cognitive recovery and perioperative experience for adults 65 years and older undergoing surgery, describes POD as a “major public health issue.”¹⁴ The incidence of POD has been associated both with preoperative vulnerabilities and—of key importance to studies such as this—the cumulative duration of intraoperative EEG burst suppression. As the current study and others have found, processed EEG monitoring during surgery, by helping clinicians minimize the duration of burst suppression, may lower the rate of POD.^1,15-19

@Masimo | #Masimo

About Masimo

Masimo (NASDAQ: MASI) is a global medical technology company that develops and produces a wide array of industry-leading monitoring technologies, including innovative measurements, sensors, patient monitors, and automation and connectivity solutions. Our mission is to improve patient outcomes and reduce the cost of care. Masimo SET^® Measure-through Motion and Low Perfusion™ pulse oximetry, introduced in 1995, has been shown in over 100 independent and objective studies to outperform other pulse oximetry technologies.²⁰ Masimo SET^® has also been shown to help clinicians reduce severe retinopathy of prematurity in neonates,²¹ improve CCHD screening in newborns,²² and, when used for continuous monitoring with Masimo Patient SafetyNet™ in post-surgical wards, reduce rapid response team activations, ICU transfers, and costs.^23-26 Masimo SET^® is estimated to be used on more than 200 million patients in leading hospitals and other healthcare settings around the world,²⁷ and is the primary pulse oximetry at 9 of the top 10 hospitals as ranked in the 2021-22 U.S. News and World Report Best Hospitals Honor Roll.²⁸ Masimo continues to refine SET^® and in 2018, announced that SpO₂ accuracy on RD SET^® sensors during conditions of motion has been significantly improved, providing clinicians with even greater confidence that the SpO₂ values they rely on accurately reflect a patient’s physiological status. In 2005, Masimo introduced rainbow^® Pulse CO-Oximetry technology, allowing noninvasive and continuous monitoring of blood constituents that previously could only be measured invasively, including total hemoglobin (SpHb^®), oxygen content (SpOC™), carboxyhemoglobin (SpCO^®), methemoglobin (SpMet^®), Pleth Variability Index (PVi^®), RPVi™ (rainbow^® PVi), and Oxygen Reserve Index (ORi™). In 2013, Masimo introduced the Root^® Patient Monitoring and Connectivity Platform, built from the ground up to be as flexible and expandable as possible to facilitate the addition of other Masimo and third-party monitoring technologies; key Masimo additions include Next Generation SedLine^® Brain Function Monitoring, O3^® Regional Oximetry, and ISA™ Capnography with NomoLine^® sampling lines. Masimo’s family of continuous and spot-check monitoring Pulse CO-Oximeters^® includes devices designed for use in a variety of clinical and non-clinical scenarios, including tetherless, wearable technology, such as Radius-7^® and Radius PPG™, portable devices like Rad-67^®, fingertip pulse oximeters like MightySat^® Rx, and devices available for use both in the hospital and at home, such as Rad-97^®. Masimo hospital automation and connectivity solutions are centered around the Masimo Hospital Automation™ platform, and include Iris^® Gateway, iSirona™, Patient SafetyNet, Replica™, Halo ION™, UniView^®, UniView :60™, and Masimo SafetyNet™. Additional information about Masimo and its products may be found at www.masimo.com. Published clinical studies on Masimo products can be found at www.masimo.com/evidence/featured-studies/feature/.

ORi and RPVi have not received FDA 510(k) clearance and are not available for sale in the United States. The use of the trademark Patient SafetyNet is under license from University HealthSystem Consortium.

References

1. Xu N, Li L, Wang T, Jiao L, Hua Y, Yao D, Wu J, Ma Y, Tian T, Sun X. Processed Multiparameter Electroencephalogram-Guided General Anesthesia Management Can Reduce Postoperative Delirium Following Carotid Endarterectomy: A Randomized Control Trial. Front Neurol. 12 July 2021. 12:666814. doi: 10.3389/fneur.2021.666814.
2. Lipowski ZL. Delirium in the elderly patient. N Engl J Med. (1989) 320:578–82. doi: 10.1056/NEJM198903023200907.
3. Khadka J, McAlinden C, Pesudovs K. Cognitive trajectories after postoperative delirium. N Engl J Med. (2012) 367:30–9. doi: 10.1056/NEJMoa1112923.
4. Inouye SK, Westendorp RG, Saczynski JS. Delirium in elderly people. Lancet. (2014) 383:911–22. doi: 10.1016/S0140-6736(13)60688-1.
5. Bin Abd Razak HR, Yung WY. Postoperative delirium in patients undergoing total joint arthroplasty: a systematic review. J Arthroplasty. (2015) 30:1414–7. doi: 10.1016/j.arth.2015.03.012.
6. Salluh JI, Wang H, Schneider EB, Nagaraja N, Yenokyan G, Damluji A, et al. Outcome of delirium in critically ill patients: systematic review and meta-analysis. BMJ. (2015) 350:h2538. doi: 10.1136/bmj.h2538.
7. Inouye SK. The dilemma of delirium: clinical and research controversies regarding diagnosis and evaluation of delirium in hospitalized elderly medical patients. Am J Med. (1994) 97:278–88. doi: 10.1016/0002-9343(94)90011-6.
8. Crocker E, Beggs T, Hassan A, Denault A, Lamarche Y, Bagshaw S, et al. Long-term effects of postoperative delirium in patients undergoing cardiac operation: a systematic review. Ann Thoracic Surg. (2016) 102:1391–9. doi: 10.1016/j.athoracsur.2016.04.071.
9. Mashour GA, Woodrum DT, Avidan MS. Neurological complications of surgery and anaesthesia. Br J Anaesthesia. (2015) 114:194–203. doi: 10.1093/bja/aeu296.
10. American Society of Anesthesiologists. Perioperative Brain Health Initiative Website. (2018). Available online at: https://www.asahq.org/brainhealthinitiative (accessed September 16, 2018).
11. Mohanty S, Rosenthal RA, Russell MM, Neuman MD, Ko CY, Esnaola NF. Optimal perioperative management of the geriatric patient: a best practices guideline from the American College of Surgeons NSQIP and the American Geriatrics Society. J Am College Surgeons. (2016) 222:930–47. doi: 10.1016/j.jamcollsurg.2015.12.026.
12. O’Mahony R, Murthy L, Akunne A, Young J. Synopsis of the National Institute for Health and Clinical Excellence guideline for prevention of delirium. Ann Internal Med. (2011) 154:746–51. doi: 10.7326/0003-4819-154-11-201106070-00006.
13. National Institute for Health and Care Excellence. Delirium in Adults. London: National Institute for Health and Care Excellence (2014).
14. Brain Health. ASA. https://www.asahq.org/in-the-spotlight/brain-health. Accessed 13 Nov 2021.
15. Tang CJ, Jin Z, Sands LP, Pleasants D, Tabatabai S, Hong Y, Leung JM. ADAPT-2: A Randomized Clinical Trial to Reduce Intraoperative EEG Suppression in Older Surgical Patients Undergoing Major Noncardiac Surgery. Anesth Analg 2020; 131(4):1228-1236.
16. Radtke FM, Franck M, Lendner J, Krüger S, Wernecke KD, Spies CD. Monitoring depth of anaesthesia in a randomized trial decreases the rate of postoperative delirium but not postoperative cognitive dysfunction. Br J Anaesthesia. (2013) 110:98–105. doi: 10.1093/bja/aet055.
17. MacKenzie KK, Britt-Spells AM, Sands LP, Leung JM. Processed electroencephalogram monitoring and postoperative delirium: a systematic review and meta-analysis. Anesthesiology. (2018)129:417–27. doi: 10.1097/ALN.0000000000002323.
18. Sieber FE, Zakriya KJ, Gottschalk A, Blute MR, Lee HB, Rosenberg PB, et al. Sedation depth during spinal anesthesia and the development of postoperative delirium in elderly patients undergoing hip fracture repair. Mayo Clin Proc. (2010) 85:18–26. doi: 10.4065/mcp.2009.0469.
19. Whitlock EL, Torres BA, Lin N, Helsten DL, Nadelson MR, Mashour GA, et al. Postoperative delirium in a substudy of cardiothoracic surgical patients in the BAG-RECALL clinical trial. Anesth Analg. (2014) 118:809–17. doi: 10.1213/ANE.000000000000002.
20. Published clinical studies on pulse oximetry and the benefits of Masimo SET® can be found on our website at http://www.masimo.com. Comparative studies include independent and objective studies which are comprised of abstracts presented at scientific meetings and peer-reviewed journal articles.
21. Castillo A et al. Prevention of Retinopathy of Prematurity in Preterm Infants through Changes in Clinical Practice and SpO₂ Technology. Acta Paediatr. 2011 Feb;100(2):188-92.
22. de-Wahl Granelli A et al. Impact of pulse oximetry screening on the detection of duct dependent congenital heart disease: a Swedish prospective screening study in 39,821 newborns. BMJ. 2009;Jan 8;338.
23. Taenzer A et al. Impact of pulse oximetry surveillance on rescue events and intensive care unit transfers: a before-and-after concurrence study. Anesthesiology. 2010:112(2):282-287.
24. Taenzer A et al. Postoperative Monitoring – The Dartmouth Experience. Anesthesia Patient Safety Foundation Newsletter. Spring-Summer 2012.
25. McGrath S et al. Surveillance Monitoring Management for General Care Units: Strategy, Design, and Implementation. The Joint Commission Journal on Quality and Patient Safety. 2016 Jul;42(7):293-302.
26. McGrath S et al. Inpatient Respiratory Arrest Associated With Sedative and Analgesic Medications: Impact of Continuous Monitoring on Patient Mortality and Severe Morbidity. J Patient Saf. 2020 14 Mar. DOI: 10.1097/PTS.0000000000000696.
27. Estimate: Masimo data on file.
28. http://health.usnews.com/health-care/best-hospitals/articles/best-hospitals-honor-roll-and-overview.

Forward-Looking Statements

This press release includes forward-looking statements as defined in Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, in connection with the Private Securities Litigation Reform Act of 1995. These forward-looking statements include, among others, statements regarding the potential effectiveness of Masimo Root ^® and SedLine ^®, and the combination of Masimo SedLine processed electroencephalogram parameters (“Combined Parameters”) in reducing postoperative delirium. These forward-looking statements are based on current expectations about future events affecting us and are subject to risks and uncertainties, all of which are difficult to predict and many of which are beyond our control and could cause our actual results to differ materially and adversely from those expressed in our forward-looking statements as a result of various risk factors, including, but not limited to: risks related to our assumptions regarding the repeatability of clinical results; risks related to our belief that Masimo’s unique noninvasive measurement technologies, including Root, SedLine, and the Combined Parameters, contribute to positive clinical outcomes and patient safety; risks that the researchers’ conclusions and findings may be inaccurate; risks related to our belief that Masimo noninvasive medical breakthroughs provide cost-effective solutions and unique advantages; risks related to COVID-19; as well as other factors discussed in the “Risk Factors” section of our most recent reports filed with the Securities and Exchange Commission (“SEC”), which may be obtained for free at the SEC’s website at www.sec.gov. Although we believe that the expectations reflected in our forward-looking statements are reasonable, we do not know whether our expectations will prove correct. All forward-looking statements included in this press release are expressly qualified in their entirety by the foregoing cautionary statements. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of today’s date. We do not undertake any obligation to update, amend or clarify these statements or the “Risk Factors” contained in our most recent reports filed with the SEC, whether as a result of new information, future events or otherwise, except as may be required under the applicable securities laws.

Contacts

Masimo
Evan Lamb

949-396-3376

elamb@masimo.com