Aspect Medical Systems Highlights New Cost-Benefit Research Results, Sponsors Continuing Education at AACN National Teaching Institute Exposition.

Business Editors/Health/Medical Writers

NEWTON, Mass.--(BUSINESS WIRE)--May 21, 2003

Duke Study Demonstrates $126 Decrease in Cost of Sedative Drugs

Used Per Patient With BIS Monitoring

Aspect Medical Systems (NASDAQ: ASPM), the global leader in clinically proven technology that measures the effects of anesthetics and sedatives on the brain, is exhibiting and sponsoring numerous continuing education programs at the American Association of Critical Care Nurses (AACN) National Teaching Institute (NTI(TM)) and Critical Care Exposition in San Antonio, May 19 - 22. Clinicians from Duke University Medical Center will also be presenting research that demonstrates how BIS(R) monitoring was used to maintain the appropriate level of sedation while decreasing use of sedative medication. In the study, researchers calculated a cost savings of $126 per day, per patient when the BIS monitor was used to monitor the brain for optimal sedation.

"The study confirmed our suspicion that without an objective measure of brain state, clinicians in the critical care unit tend to oversedate patients. This is common because we want to make certain that patients are comfortable and free from pain and unpleasant recall," said leading investigator DaiWai Olson, RN, BSN, CCRN, a staff nurse at Duke University Medical Center and Ph.D. candidate at the University of North Carolina at Chapel Hill. "Our study showed that by using BIS as an objective measure of sedation, we could safely reduce the amount of sedative drug we were giving most patients." He continued, "The cost savings from decreased drug usage is just the tip of the iceberg. There are numerous other benefits of sedation monitoring with BIS that have the potential to improve care for the patient by reducing length of stay, the risk for complications, and the need for additional diagnostic testing, such as CT scans."

Over and undersedation of patients is a widely recognized challenge in the critical care unit where sedation assessment has been guided primarily by vital signs or subjective sedation assessment scales - approaches that may not be sufficient to achieve optimal patient assessment. The critical care nursing community continues to demonstrate significant interest in addressing this challenge with BIS technology as evidenced by approximately 1,500 nurses in attendance at Aspect's NTI continuing education (CE) sessions.

Charlie Forbes, RN, CCRN and clinical educator at Indiana University Hospital, presented at one of the Aspect sponsored CE sessions. "BIS transformed clinical practice in our critical care units and I'm pleased to see such strong peer interest in learning from our experience," said Forbes. "Assessing sedation in critically ill patients is particularly challenging because these patients often require treatment for multiple conditions and are frequently unable to communicate. The BIS provides the objective information that we need to assess sedation and optimize comfort and care. It has proven to be valuable in numerous clinical situations, including monitoring drug induced coma cases, bedside procedures and end-of-life care, as well as monitoring patients that require neuromuscular blocking agents or mechanical ventilation."

Commenting on the strong presence at the AACN/NTI meeting, Joan Kinniburgh, RN, BSN, MBA, critical care marketing manager for Aspect stated, "We continue to see high demand for the objective information that BIS provides to help critical care teams make better, more informed decisions. As the primary providers of comfort and care for critically ill patients, critical care nurses are an essential customer to facilitate widespread adoption of BIS in the ICU."

BIS technology is also being displayed on the show floor as an integrated module solution at the GE Medical Systems Information Technologies, Philips and Spacelabs Medical exhibits.

About BIS Monitoring

BIS monitoring provides direct information about the effects of anesthetics and sedatives on the brain. The technology works by placing a BIS sensor on a patient's forehead to obtain information from electrical brain activity, or EEG. The BIS monitor then translates this information into a single number from 100 (indicating an awake patient) to zero (indicating the absence of brain electrical activity) that objectively represents each patient's level of consciousness. BIS monitoring thereby enables clinicians to minimize the risk of under- and over- dosing of anesthetics and sedatives. Other vital signs, such as heart rate and blood pressure, do not correlate with depth of consciousness and are unreliable measures of adequate anesthesia and sedation.

About Aspect Medical Systems, Inc.

Aspect Medical Systems, Inc. (NASDAQ: ASPM) is a global market leader in brain monitoring technology. Aspect's Bispectral Index(R) (BIS) technology directly measures the effects of anesthetics and sedatives on the brain and has been used to assess more than six million patients. BIS is currently in use in the operating rooms and intensive care units of more than 55 percent of the best-ranked hospitals in the U.S. (based on a U.S. News & World Report ranking) and has been the subject of approximately 1,200 published articles and abstracts. BIS is available in more than 160 countries with a worldwide installed base of monitors and BIS modules of approximately 16,000. Aspect has secured OEM agreements with seven leading manufacturers of patient monitoring systems and partnerships with six of the largest group purchasing organizations in the United States. Based in Newton, Mass., Aspect employs more than 200 people worldwide. For more information, visit Aspect's web site at http://www.aspectmedical.com.

Safe Harbor Statement

Certain statements in this release are forward-looking and may involve risks and uncertainties, including Aspect's expectations concerning the expected benefits of BIS in the critical care setting and its ability to grow the market for its products worldwide and build value for its shareholders. There are a number of factors that could cause actual results to differ materially from those indicated by these forward-looking statements. For example, Aspect may not be able to achieve widespread market acceptance of its BIS monitoring technology or to compete with new products or alternative techniques that may be developed by others including third-party anesthesia monitoring products approved by the FDA. Aspect also faces competitive and regulatory risks relating to its ability to successfully develop and introduce enhancements and new products. In addition, Aspect has limited sales and marketing experience both in the U.S. and internationally and if it is unable to develop and implement a successful sales and marketing strategy, including with respect to its own sales force, domestic and international distributors, original equipment manufacturers and other direct and indirect sales channels, it will not be able to generate meaningful product revenue. Aspect's ability to become and remain profitable will depend upon its ability to promote frequent use of the BIS system so that sales of its BIS sensors increase. Aspect will not be profitable if hospitals and anesthesia providers do not buy and use its BIS systems in sufficient quantities. Cases of surgical awareness during monitoring with the BIS system and significant product liability claims are among the factors that could limit market acceptance. There are other factors that could cause Aspect's actual results to vary from its forward-looking statements, including without limitation those set forth under the heading "Factors Affecting Future Operating Results" in Aspect's Quarterly Report on Form 10-Q for the quarter ended March 29, 2003, as filed with the Securities and Exchange Commission. In addition, any forward-looking statements in this press release represent Aspect's views only as of the date of this press release and should not be relied upon as representing Aspect's views as of any subsequent date. While Aspect may elect to update forward-looking statements in the future, it specifically disclaims any obligation to do so, even if its expectations change. Therefore, you should not rely on these forward-looking statements as representing Aspect's views as of any date subsequent to the date of this press release.

Bispectral Index and BIS are registered trademarks of Aspect Medical Systems, Inc. and are registered in the USA, EU and other countries.