Is “HAL” coming to a GI suite near you?

  • Sibert, Karen, MD, FASA
| Jun 16, 2013

Movie buffs and science fiction fans certainly remember HAL, the computer in 1968’s hit movie “2001: A Space Odyssey.” Considered one of the greatest villains in film history, HAL was capable of reasoning and language processing to assist the astronauts on their space mission. Ultimately, however, HAL decided that its best course of action was to kill all the astronauts. “I am putting myself to the fullest possible use,” said HAL, “which is all I think that any conscious entity can ever hope to do.”

Forty-five years later, the FDA in its wisdom has given premarket approval to the Sedasys® Computer-Assisted Personalized Sedation System, developed by Ethicon Endo-Surgery Inc. The device has the potential to “redefine sedation delivery,” according to Ethicon’s press release, with propofol sedation “personalized to the needs of each patient, by precisely integrating drug delivery and comprehensive patient monitoring.” The Sedasys device is designed for “healthy” adult patients who undergo colonoscopy and esophagogastroduodenoscopy (EGD) procedures electively.

Ethicon expects to introduce the system into clinical practice on a limited basis in 2014 to address “the growing preference for propofol sedation in gastroenterology by more closely matching the skill level of the sedation delivery team with the actual requirements of less complex cases.”

According to the FDA’s overview, the Sedasys is a “first-of-a-kind device that will allow non-anesthesia practitioners to administer propofol during colonoscopy and EGD procedures.” It links clinical monitors to an IV infusion pump, and will automatically modify or stop the infusion if it detects “signs associated with oversedation” such as oxygen desaturation.

You don’t have to read much between the lines to conclude that the goal here is to make colonoscopies and EGDs cheaper by allowing people other than qualified anesthesia practitioners to administer propofol.

The FDA has given everyone its blessing to ignore the propofol package insert’s warning that propofol “should be administered only by persons trained in the administration of general anesthesia.” The FDA appears to think it will be enough for GI teams to take part in a “simulation-based moderate sedation training program” that will provide “expert instruction in the pharmacology of propofol and airway management.”

The New York Times must have made Ethicon very happy, in a front-page article on June 2, by claiming that colonoscopy costs are causing the U.S. to lead the world in health expenditures. While facility fees are the biggest targets for criticism, anesthesiologists are in the cross hairs too. The Times estimated that payments to anesthesiologists for colonoscopy sedation quadrupled between 2003 and 2009, and that eliminating anesthesiologist services could save $1.1 billion a year.

So what’s the problem?

The problem isn’t actually with the Sedasys device or its clever developers. You can’t stop technology. I’ve argued before that anesthesiologists are being extremely shortsighted to think that we need to personally provide all sedation or general anesthesia (see my previous post, “Vinyl records and the future of medicine”). Technology can help us monitor more efficiently, and use our advanced training more effectively.

Jonathan Cohn’s recent article in The Atlantic, “The Robot Will See You Now", looks at the often scary future of technology in medicine. He quotes Dr. David Lee Scher, president of DLS Healthcare Consulting, who thinks physicians won’t be seeing patients as much in the future. “I think they are transitioning into what I see as super-quality-control officers,” Dr. Scher says, “overseeing physician assistants, nurses, nurse-practitioners, etc., who are really going to be the ones who see the patients.” By this logic, the development of Sedasys is simply another step toward reducing direct physician involvement when a less costly level of care may suffice.

What happens, though, when the lineup of GI patients for colonoscopies and EGDs includes through some scheduling error a patient who isn’t essentially healthy? That could include many patients we commonly see in the GI suite—those with sleep apnea, obesity, heart disease, or other complicating problems. The FDA specifies that Sedasys shouldn’t be used for any patient with a full stomach, but would that include achalasia? Severe reflux? Diabetic gastroparesis? What are the odds that the team using a Sedasys device will actually stop when they should and call for an anesthesiologist to help? Time is money, and delays annoy everyone. There are so many conditions that can make sedation risky, and the push for efficiency can work against the individualization of care for the high-risk patient.

Everyone who gives anesthesia knows how easy it is for a patient on propofol sedation to slip over the dividing line between a patent airway and one that is becoming progressively more obstructed. The delivery of supplemental oxygen can delay the recognition that the airway is obstructed because it delays oxygen desaturation. If airway obstruction is just a function of the propofol dose, then it should be easy to write a recipe for propofol delivery that would prevent airway obstruction from happening. But some patients snore and obstruct their airways during sedation worse than others, and one person’s response to a given propofol dose is very different from another’s.

The key problem with Sedasys is this: If oxygen desaturation occurs, and the device stops delivering propofol, who in the room has the skills to manage the airway while the patient recovers? This is especially problematic during EGD, when airway obstruction may be more severe because a large endoscope takes up much of the territory.

The American Society of Anesthesiologists (ASA) is doing what it can to monitor the incursion of Sedasys into clinical practice and its future economic effect on the profession of anesthesiology. It is implementing a “three-prong strategy” to review the FDA’s conditions of approval, meet with Ethicon representatives, and “explore an enhanced role for ASA with the FDA relative to this device and other future devices.” The ASA wasn’t initially successful in its attempts to block FDA approval of Sedasys, so it remains to be seen how effective these new efforts may be. It’s worth noting that a prominent Stanford anesthesiologist, Dr. Steven Shafer, chaired the “Anesthesia Advisory Panel” that guided the development of Sedasys.

It will take time and larger outcome studies to assess the clinical risk of propofol sedation guided by the Sedasys device. Used as intended, with properly selected patients, severe adverse outcomes may be rare. By actuarial standards, the cost in dollars saved for a large cohort of patients may be quite favorable, even compared against the cost incurred with a single severe adverse outcome. As always, though, the cost vs. benefit ratio looks different if the poor outcome happens to be yours.

The Institute of Medicine famously opined in its report, “The Future of Nursing,” that advanced practice nurses should be able to practice “to the full extent of their education and training.” This report has been the springboard to the Affordable Care Act’s broad encouragement of any and all initiatives to expand scope of practice and reduce the role of physicians. Looked at from this perspective, the development of the Sedasys device simply expands scope of practice in another dimension. Why can’t a machine guide sedation? After all, as HAL would say, it’s just trying to put itself to the fullest possible use.

Leave a comment