Cleveland Clinic, Aspect Medical Systems collaborate to study anesthesia outcomes

July 29, 2009 by Mary Vanac


CLEVELAND, Ohio—The Cleveland Clinic will study the outcomes of patients who received anesthesia during surgeries through a five-year collaboration and licensing agreement with Aspect Medical Systems Inc.in Norwood, Mass.

The goal of the study is to find clinical practices that minimize patient deaths in the year following their surgeries. "People almost never die during anesthesia. And if they do, it was not preventable because it was caused by underlying disease or trauma," said Dr. Daniel Sessler, professor and chair of the Department of Outcomes Research at the Clinic.

"On the other hand, mortality after surgery is not rare at all. Five percent of surgical patients are dead a year later," Sessler said. That percentage is closer to 10 percent for patients over 65 years old. Sessler and about a dozen of his Clinic colleagues will work with Aspect Medical to try to figure out whether anesthesia has anything to do with the deaths, and if so, find anesthesia-related "interventions" that minimize bad outcomes.

The agreement combines the Clinic's sophisticated electronic health record systems, skilled investigators and clinicians—and access to tens of thousands of patients—with Aspect Medical's brain wave-measuring device that tells how anesthesia is affecting patients, said Sessler, who has worked with Aspect on research projects for about 20 years. Sessler has no direct financial ties to Aspect Medical. Rather, the company that makes brain monitoring technology sponsors research projects at the Clinic, including the anesthesia practices project.

Though the project is expected to generate revenue for the Clinic, "almost all research is a money loser," Sessler said. "The cost will likely exceed what we get from Aspect." The Massachusetts company also has agreed on licensing terms for any intellectual property that emerges from the project, Aspect Medical said in a written statement.

To begin the project, Aspect Medical and Clinic investigators will analyze millions of Centers for Medicare and Medicaid Services records of past Clinic surgical patients to refine a way to gauge patients' medical risk, Aspect said. The investigators will develop methods to measure and eventually predict post-surgical outcomes, based on anesthesia practices and patient risk factors. Findings of the study would be used to educate clinicians about the most effective anesthesia practices.

The first clinical target of the study will be what anesthesiologists call a "triple low"—low level of tolerating anesthesia, low brain-wave activity and low blood pressure, Sessler said. Individually, these low readings would say little about patient status. However, Sessler and his fellow investigators suspect that together, the three low readings could predict poor patient outcomes.

Such "comparative effectiveness" studies are being encouraged by the Obama administration as a way to raise the quality of medical care and lower its cost. About $1.1 billion of federal money was set aside for comparative effectiveness research in this year's American Recovery and Reinvestment Act, according to the Agency for Healthcare Research and Quality.

"Hospitals and clinicians are increasingly interested in delivering greater patient value by identifying clinical practices that result in better outcomes, higher quality and lower costs," Nassib Chamoun, president and CEO of Aspect Medical Systems, in his company's statement. "We believe that anesthetic management decisions play a key role in enabling better patient outcomes Ultimately, our goal is to define interventions and decision support systems that will lead to further improvements in clinical practice and patient outcomes."

In general, effectiveness research lacks the controls and rigor of the efficacy research that clinicians do for regulatory approval of new drugs or medical devices. Efficacy research, for instance, requires that drugs or devices in studies be assigned randomly to patients, Sessler said. This practice seeks to avoid biased research that might result from picking certain patients.

However, effectiveness research has its own strengths. Effectiveness trials "look at populations or systems in real-world environments," Sessler said. This type of research looks at the ways a drug or device might be used, not used or used imperfectly by clinicians in a realistic setting rather than a controlled one, he said.

Aspect Medical and the Clinic propose to combine the strenghts of both types of studies to do a "randomized effectiveness" study. "That has not been done previously," Sessler said.

To add randomness to an effectiveness study of the triple-low theory, for example, investigators might use electronic record systems to alert half of anesthesiologists to raise their patient's blood pressure—the only one of the three lows that can be controlled, he said. The other half of anesthesiologists would not receive the alert.

"If the results confirm our theory, this will be a way for anesthesiologists to extend their influence from the perioperative period to the weeks and months after surgery where most of the adverse outcomes occur," Sessler said.