Computer-Assisted Personalized Sedation—The Beginning or the End of the Anesthesia Provider?

Steven Boggs, MD, MBA
Associate Professor, Anesthesiology
The Icahn School of Medicine at Mount Sinai, Manhattan, NY

Computers and improvements in modern anesthesia delivery have gone hand-in-hand. In 1952 Himmelstein and Scheiner reported that they began using an instrument called the cardiotachoscope and found it useful during surgery. In 1958 Ben Ettelson and James Reeves started Spacelabs to develop systems for the United States Air Force for monitoring vital signs of U.S. astronauts.1 This technology returned to earth, with the 1970s witnessing the expansion of digital electronics in operating rooms (ORs) and critical care units (CCUs). The 1980s saw clinical penetration of modularity and utilization of saturation and end-tidal carbon dioxide monitoring. As pharmaceuticals developed shorter and shorter clinical half-lives and microprocessor technology continued to improve, the concepts of closed-loop (CL) anesthesia, targeted-controlled infusion (TCI) devices and other computer controlled delivery systems moved from theoretical possibilities to clinically relevant systems.2

In the late 1990s Dr. Randy Hinkle, an anesthesiologist, formulated the initial concept that ultimately became Computer- Assisted Personalized Sedation (CAPS). Ethicon manufactured and distributed the only FDA-approved CAPS system, named Sedasys®, until it decided to “pull the system to focus on other opportunities.”3 It is unclear at present whether another company will take over this technology or if the healthcare facilities in which Sedasys is in use will continue to use it. Nonetheless, the technical, safety and cost implications of systems such as Sedasys are an interesting case study.

The actual specifics of how the system functions are beyond the scope of this article. Company material and peer-reviewed literature describe the operation of the system. Significantly, Sedasys is neither a CL delivery system nor a TCI device. Propofol is delivered via continuous infusion rather than a bolus dose and Sedasys integrates oxygen saturation, exhaled carbon dioxide, non-invasive blood pressure and heart rate (EKG) monitoring. As recommended by the ASA Practice Guidelines for Sedation and Analgesia by Non-Anesthesiologists, patient responsiveness is also monitored by an Automated Response Monitor (ARM). Studies have shown that patients lose response to the ARM before they transition from Moderate Sedation (MS) into Deep Sedation (DS). Importantly, Sedasys is intended for the administration of mild to moderate sedation (MS) for either a colonoscopy or an esophagogastroduodenoscopy (EGD) (not both procedures on the same patient).

Ethicon slowly introduced Sedasys into the market. Initially, only two sites used the device. Then the Virginia Mason Medical Center (Seattle, WA), the Grace Clinic (Lubbock, TX), Promedica Toledo Hospital (Toledo, OH) and Loma Linda University Medical Center (Loma Linda, California) adopted the Sedasys system. Other centers were ready to begin using the system prior to the announcement that Ethicon was exiting the market, but the company did not release the names of those centers.

Virginia Mason initially started with two devices, increasing this number gradually to the current number of eight Sedasys units. Both Dr. Andrew Ross, Section Head for Gastroenterology and Dr. Wade Weigel, Section Head of out-of-OR anesthesia at Virginia Mason have indicated that the Sedasys system achieved several objectives for the hospital, for the gastroenterology department and for Virginia Mason patients. It provided efficiency gains within the endoscopy unit. Both patients and gastroenterologists have been satisfied with the system and there have been no severe airway or cardiorespiratory complications in more than 8,500 cases performed to date.4

There are several limitations imposed on the users of Sedasys. As specified in the FDA approval, an anesthesia provider must be immediately available if required should airway management or other patient management issues arise. The unanswered question here is, “How immediately available is immediately available?” This precludes the use of the device in isolated gastroenterology offices and restricts its use to larger centers. Even in these centers, however, it is unclear how anesthesia provider availability will be allocated.5 Also, there is a limit to the amount of concomitant medications the patient can receive in addition to the propofol infusion.

There is also the issue of revenue and costs. Based on the information from my colleagues at Anesthesia Business Consultants, total anesthesia payment for both EGD or colonoscopy (not both at the same time) procedures from January to June 2015, excluding government payees, was approximately $300.00. When I spoke with Ethicon about their pricing models prior to their decision to pull the system from the market, the comment was, “We have presented a couple of different sedation delivery models to selected regional payers including models that include payment for anesthesia medical direction or anesthesia patient selection and assessment are actively working with two payers to develop pilots that provide reimbursement to those willing to adopt those models. We would like to invite any of the readers to contact us should they be interested in exploring new business models leveraging this technology.

In current payment systems, the gastroenterologist receives her/his fee and the anesthesia payment is separate from that fee. There are growing financial incentives in the U.S. healthcare system to develop new methods of both payment and procedural sedation that decrease anesthetist involvement in certain cases. Throughout Europe most colonoscopies and EGDs are performed without an anesthesiologist. This is especially the case in Germany and Switzerland and their outcomes are no worse than those seen in the USA.6 Also, in the United States, from 2003 to 2009 there was a significant expansion of anesthesia involvement in sedation for colonoscopies. This expansion was greatest in patients classified as either ASA I or II, not in patients having multiple comorbidities.7

In the past Sedasys could be purchased or leased for approximately $200,000.00. In this case, the per-procedure charge for disposables was lower (approximately $110.00 – $120.00). More recently, one could buy only the disposables on a per-case basis at a slightly higher charge if the machine were not purchased (approximately $150.00 for disposables per procedure). In the former case, at least 2,000 cases per room each year would have to be performed to optimize financial performance.

Constraints on the healthcare budget will only grow in severity. As our healthcare system transitions from a fee-for-service to a value-based payment model, anesthesiologists will have to collaborate with other specialties to reduce total costs. The Rand Corporation conducted a study for the ASA in 2013 and its likely projection is that the supply of anesthesiologists will peak in 2017 and decline thereafter.8 If you couple this forecast with the explosive growth of NORA procedures, the need for anesthesiologists will not be eliminated. Alternative payment models where reimbursement for the department of anesthesiology’s contribution to net hospital revenue and involvement in a unit with Sedasys or other CAPS systems will need to be created.

Meanwhile, data from the CDC demonstrate that our country is not screening all of the patients we should for colorectal cancer. Colorectal cancer remains the second leading cause of cancer death in our country and the annual expenditure for this specific diagnosis was $14 billion dollars in 2012.9 We do need to expand our screening of patients but we must do so in a cost-effective manner.

One critical issue concerning the use of Sedasys or any other technology for the administration of mild-to-moderate sedation is the framing of patient expectations. Most clinicians in anesthesiology are familiar with the dread look one receives when discussing a regional block with an orthopedic patient whose orthopedist has forgotten to mention a nerve block to them. Likewise, with a system such as Sedasys which provides mild-to-moderate sedation, it is critical that the gastroenterologist explain to the patient that they may remember parts of the procedure and experience some discomfort. The patient should not anticipate “having the best sleep of their life” and they should not anticipate being unconscious for the procedure.

Anesthesia providers have voiced several concerns about technologies such as Sedasys.10 It must be emphasized that Sedasys is only the first and will not be the last of more and more advanced systems for the administration of either sedation or the intraoperative management of depth of anesthesia. Its introduction was delayed by a lengthy FDA approval process. The anesthesia community will and must continue to articulate and advocate for patient safety recognizing that with systems such as Sedasys patient selection is a critical area for both patient selections and exclusion criteria.

Experienced anesthesia providers also note that they can efficiently sedate patients for EGDs and colonoscopies more rapidly than can be achieved with the Sedasys system. This fails to account for total process time. As many other industries have recognized, rapid processing at one step is not the objective.

Rather, the objective is total production (manufacturing) or patients treated (healthcare). The concept of “task time”11 recognizes that each step in complex processes must be coordinated. Total output rather than sub-step performance is the objective.

Computers will continue to help us deliver more precise and safer care to patients. Yet for the foreseeable future anesthesia will not become redundant. The United States Department of Labor Occupational Information Network still lists anesthesiology as a “Bright Outlook Occupation.”12 This means that anesthesiology is projected to grow much faster than average occupations. A fascinating study was conducted by Frey and Osborne of Oxford in 2013. They looked at “The Future of Employment: How Susceptible are Jobs to Computerization?”13 They discovered that three variables—social intelligence, creativity and perception and manipulation—are primary determinants in whether a job may be computerized. Dishwashers, court clerks and telemarketers all have jobs at high risk of being computerized. Anesthesiology does not. To further this theme, I contacted David Dautor, PhD, Associate Department Head of the Department of Economics at the Massachusetts Institute of Technology.14 Technological change is one of his areas of expertise. His thoughts on computers in anesthesia are that:

  • Anesthesiologists will remain indispensable
  • Computers may reduce the number of anesthesiologists required per patient admission
  • If anesthesia becomes cheaper and safer there may be an output expansion effect (increased volume)
  • Medical occupations demand:
    • Deep technical expertise
    • Human flexibility
    • Problem solving
    • Creativity
    • Compassion
  • Virtuous pairing of skills makes these jobs hard to replace with either machines or non-highly-trained workers

Surgery, procedural medicine and anesthesia techniques have advanced significantly. The techniques of proceduralists and surgeons progress continually to less invasive approaches. Each of these groups is treating patients with significant comorbidities who only a few decades ago would have been classified as being “too sick for anesthesia.” The computer power available to us has grown each decade and this trend will not diminish. It can be anticipated that computers and new anesthetic delivery systems will only increase in their capabilities. While the future of Sedasys as a system is unclear, we can anticipate other systems to enter the marketplace. Anesthesiologists need to adapt to these new technologies, demonstrating that we can provide outstanding anesthetic care to sicker patients, more efficiently, in a more cost effective manner with the humane treatments that our patients deserve and expect.


1http://www.referenceforbusiness.com/history/Sh-St/Spacelabs-Medical-Inc.html
2Shafer SL, Egan T. Target-Controlled Infusions: Surfing USA Redux. Anesth Analg. 2016 Jan; 122(1):1-3.
3http://www.outpatientsurgery.net/outpatient-surgery-news-and-trends/general-surgical-news-and-reports/%20ethicon-pulling-sedasys-anesthesia-system--03-10-16%20
4Personal communication(s), Drs. Andrew Ross and Wade Wiegel.
5 https://www.asahq.org/advocacy/fda-and-washington-alerts/washington-alerts/2014/01/asa-offers-recommendations-for-using-sedasys?page=17
6World J. Gastrointest Endosc 2015 16; 7(2):102-109
7Liu H, Waxman D, Main R et. al. Utilization of Anesthesia Services During Outpatient Endoscopies and Colonoscopies and Associated Spending in 2003-2009. JAMA, 307(11)178-184.
8http://www.anacalfornia.org/bifolder/bifolder2015-17/AB890RAND_RR650_AnesthesiaManpower_2013.pdf
9 http://www.cdc.gov/vitalsigns/colorectalcancerscreening/
10 Urman RD, Maurer WG. Computer-assisted personalized sedation: friend or foe? Anesth Analg. 2014 Jul;119(1):207-11.
11 Liker JK. The Toyota Way: 14 Management Principles from the World’s Greatest Manufacturer. Chapter 8. Principle Two: Create Continuous Process Flow to Bring Problems To the Surface. McGraw-Hill, 2004.
12 http://www.onetonline.org/help/bright/%20
13 http://www.oxfordmartin.ox.ac.uk/downloads/academic/The_Future_of_Employment.pdf
14 Personal Communication, http://economics.mit.edu/faculty/dautor/papers Moravec, Hans. Robots: Mere Machine to Transcendent Mind. Chapter Three: Power and Presence: Numerical Data for the Power Curve. Oxford University Press, 1998. Figure updated. http://www.transhumanist.com/volume1/moravec.htm


Steve Boggs, MD, MBA is the Director of the Operating Room and Chief of the Anesthesia Service at the James J. Peters VA Medical Center in the Bronx, NY. He is also Associate Professor of Anesthesiology at the Icahn School of Medicine in Manhattan, NY. Dr. Boggs has been involved in the administration of anesthesia departments for over a decade. For the past several years, he has been working closely with endoscopists at Mount Sinai and elsewhere, evaluating turnover time and safety metrics and is involved in developing a curriculum for GI sedation for low-and-middle income countries and in evaluating new methods of training providers in bag/valve/mask ventilation. He can be reached at stevendaleboggs@gmail.com.