Will Anesthesiologists Be Replaced by a Machine?

Bret S. Stetka, MD; Jeffrey Apfelbaum, MD; Daniel J. Pambianco, MD


September 22, 2015

Editor's Note:
In recent months, a few hospitals in the United States have begun using an automated anesthesiology machine called the Sedasys® computer-assisted personalized sedation (CAPS) system (Ethicon US, LLC; Somerville, New Jersey) to provide sedation in routine colonoscopies and endoscopy procedures. The device is the first and only US Food and Drug Administration (FDA)-approved CAPS product, and some anesthesiologists have expressed concern that it's after their job. Medscape recently conducted email interviews with Daniel J. Pambianco, MD, a gastroenterologist based in Charlottesville, Virginia, who served as the lead investigator on the pivotal study leading to its approval, and Jeffrey Apfelbaum, MD, professor and chair, Department of Anesthesia and Critical Care, University of Chicago, Chicago, Illinois, and co-chair of the American Society of Anesthesiologists (ASA) committee on the Sedasys machine, about how CAPS technology might influence the practice of anesthesiology and gastroenterology.

Medscape: How does the Sedasys machine work?

Dr Apfelbaum: The Sedasys System is the first of a class of CAPS devices. It has been approved by the FDA to administer propofol and oxygen for the initiation and maintenance of minimal to moderate sedation in very healthy adult patients (ASA I and II patients) undergoing either routine colonoscopy or routine upper endoscopy procedures. The device limits the depth of sedation by monitoring several physiologic parameters, including patient responsiveness to an automated response device, whereby the patient squeezes a handheld switch in response to computer-generated cues. The device also contains alarms to alert medical professionals of possible concerns.

Dr Pambianco: Sedasys is a computer-assisted sedation device that integrates physiologic monitoring of the patient while delivering propofol. It allows the endoscopist/nurse team to titrate drug delivery to minimal to moderate levels of sedation while preventing oversedation. The device uses an algorithm of propofol dosing by continuous infusion controlled by the physician/nurse team to achieve the level of sedation to keep the patient comfortable for the specific endoscopic procedure. The device assists the team in monitoring the patient, giving physiologic assessments every few seconds, and prevents oversedation by alerting the team if oxygen desaturation or apnea is occurring. The device will automatically increase oxygen delivery in response to such events, alert the team, and eventually decrease or stop the infusion of propofol if the events are not corrected by the team. Only the team can restart the propofol infusion once the events are addressed.

Medscape: What are potential advantages of this machine compared with anesthesiologist-delivered care?

Dr Apfelbaum: Many patients require sedation while undergoing colonoscopy and esophagogastroduodenoscopy (EGD). Gastroenterologists may choose to administer sedation without a physician anesthesiologist during these procedures, and in these cases they typically administer a combination of benzodiazepines and narcotics. In spite of the fact that both benzodiazepines and narcotics have specific rapid-acting reversal agents, under certain circumstances (eg, failure to recognize hypoxia or cardiovascular collapse, failure to recognize overmedication, etc.) catastrophic events sometimes occur during the procedure. The pivotal study[1] for this device demonstrated that healthy patients who were sedated using the device had lower occurrences of hypoxemia compared with similarly healthy patients who received benzodiazepines or similar medications for the same procedures.

Dr Pambianco: The vast majority of routine endoscopy requires minimal to moderate sedation, which can be achieved safely with the device. Recent head-to-head data have shown more efficient dosing of propofol and less unintended deeper sedation with the device compared with anesthesiologists for routine endoscopy. In addition and most pertinent is the fact that there are insufficient numbers of anesthesia providers to administer propofol for all of the endoscopies performed in the United States.

Medscape: What disadvantages do you see associated with the machine?

Dr Apfelbaum: While the Sedasys System can safely administer sedation for healthy patients undergoing the procedures mentioned, emergencies can and do occur, even during the simplest procedures and with the healthiest patients. Unlike a CAPS device, a physician anesthesiologist can and will intervene to save the patient in these emergency situations. Additionally, many have concerns for the safety of patients if device operators do not remain in strict compliance with the limitations imposed by the FDA on the use of the device (eg, patient selection, fulfillment and maintenance of skills from the specific educational and simulation requirements, immediate availability of a trained anesthesia professional).

To address these and other concerns, ASA has issued a guidance document on CAPS devices that provides specific clinical and administrative recommendations for directors of anesthesia services that will serve to optimize safe use of the device.

Dr Pambianco: Currently the device is FDA approved for ASA I/II patients for routine endoscopy, which are the majority of procedures. It is not approved for ASA III patients or for procedures requiring longer sedation. Another limitation is for patients who will require deeper sedation for routine colonoscopy or EGD such as patients on chronic pain meds or patients who abuse alcohol.


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