Secondary Logo

Journal Logo

The Value of Sedation by Anesthesia Teams for Complex Endoscopy

Perhaps Not What You’d Think

Warner, Mary Ellen, MD; Warner, Mark A., MD

doi: 10.1213/ANE.0000000000000328
Editorials: Editorial

From the Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota.

Accepted for publication April 26, 2014.

Funding: None.

The authors declare no conflicts of interest.

Reprints will not be available from the authors.

Address correspondence to Mary Ellen Warner, MD, Department of Anesthesiology, Mayo Clinic, 200 1st St. S.W., Rochester, MN 55905. Address e-mail to

What is the value of anesthesia team–based services provided to patients undergoing complex upper gastroenterologic (GI) endoscopy? Much has been written about this topic, and the views that have been expressed are very dependent on the perspectives of the authors and the quality of data used to support wide-ranging conclusions. The benefits or disadvantages of involving anesthesia providers in the care of patients undergoing complex upper GI endoscopies are highly debatable. Therefore, it is not surprising that professional organizational practice parameters and relevant regulatory statements may conflict.1–3

In this issue, Guimaraes et al.4 report on the endoscopic and sedation complications of 9598 patients at Massachusetts General Hospital during a 5-year period. Their practice review involved 4514 endoscopic procedures performed with nurse-administered narcotic/benzodiazepine sedation during the first 30 months of the review (April 2007 through October 2010). The demographics of patients, procedure types, and complications from this 30-month cohort were then compared with those involving patients who underwent anesthesia team–administered sedation or anesthesia during the next 30 months after the institution made a change in its complex GI endoscopy practice. The authors reported that they found approximately a 75% reduction in sedation complication frequency with anesthesia team–administered sedation or anesthesia, even though the latter group had a higher percentage of patients with ASA physical status III and IV. They conclude that anesthesia team–administered sedation or anesthesia for complex (mostly) upper GI endoscopy significantly reduces sedation complications compared with nurse-administered narcotic/benzodiazepine sedation.

We are both anesthesiologists. We both work extensively in a busy complex GI endoscopy suite. And while we wholeheartedly believe that anesthesia team–administered sedation or anesthesia for this patient population can improve patient outcomes, this review by Guimaraes et al.4 unfortunately is not sufficient to confirm our beliefs. Instead, its findings are limited to 1 practice in 1 institution in which the results of a nurse-administered narcotic/benzodiazepine sedation practice more than 3 years ago are compared with anesthesia team– administered sedation or anesthesia in the subsequent, more recent 30-month period. As a retrospective review of quality data, this report’s findings are difficult to interpret as they are not based on prospectively defined parameters such as patient characteristics (e.g., body habitus, preprocedural patient use of opioids, presence of obstructive sleep apnea), type of sedation/anesthesia used, or outcomes. For example, a close review of Table 1 in the report provides readers with no clear definitions for outcomes as common as hypoxemia, hypotension, and unplanned airway intervention.

There are many issues that need to be considered by readers as they determine how to use this report’s findings in their own practices. Readers must understand that a change in practice was made at the authors’ institution in 2010 that resulted in patients being assigned to either nurse-administered narcotic/benzodiazepine sedation or anesthesia team–administered sedation or anesthesia. This assignment appears to have been based primarily on procedure type (e.g., endoscopic retrograde cholangiopancreatography and endoscopic ultrasound). Triage criteria beyond procedure type for these and other endoscopic procedures do not appear to have been specifically used, although the authors note that patients, presumably undergoing other endoscopic procedures, could be referred for reasons of severe comorbid illnesses, previous sedation failures, or substance abuse for anesthesia team–administered sedation or anesthesia. How often and how well the referral process worked is not clear. To ensure that all patients undergo specific triage for endoscopic procedures, a triage plan based on patient characteristics and diseases as well as procedure types would be beneficial.

There are other issues that make it difficult to use the results of this report to support extended use of anesthesia team–administered sedation or anesthesia for complex endoscopic procedures. First, clinical practices change over time, and this review period is a split 30/30 months. Did the extent of proceduralist interventions change during the 2 epochs? In general, as proceduralists work on patients who have deeper sedation or anesthesia and develop a sense of improved outcomes or relief from not having direct responsibility for sedation/anesthesia while doing procedures, they may attempt more invasive or difficult procedures. For example, an endoscopic retrograde cholangiopancreatography can be relatively noninvasive or it can involve placement of stents, biopsies of multiple tissues, and variations in tissue damage and inflammation. Distinctions regarding these procedures are hard to make in retrospective reviews. A variation in complexity of procedures, even when grouped under a single definition, is one of the issues that need to be addressed in historical comparison reviews.

Second, how did the care provided by the nurses administering narcotics/benzodiazepines differ from that provided by the anesthesia teams? The authors do not report if there was any difference. Did the anesthesia team use general anesthesia often? Did they use propofol sedation? Were the great majority of the anesthesia team patients sedated with narcotics/benzodiazepines, similar to patients sedated by nurses? This information is crucial to understand how the 2 time periods in this report differed, if at all.

Third, the authors used complication data obtained primarily from a GI-oriented database. Our experience has been that proceduralists who oversee nurse-provided sedation (while also performing procedures) are more likely to document sedation complications compared with proceduralists who have been relieved from the responsibility of providing sedation oversight. The authors would help readers by providing insight into this potential confounding factor and highlight more extensively why they elected to use the GI-oriented database instead of an anesthesia-focused one for the second half of their review period.

Would answers to these questions make a difference when comparing outcomes of one provider type with another? It’s hard to know. However, the lack of answers to these relatively straightforward questions plus the absence of well-defined patient/procedure characteristics and outcomes make interpretation by readers and application of the results difficult.

So what is the value of this report to readers? There are several points of interest. The authors suggest that the use of anesthesia team–administered sedation or anesthesia reduced the percentage of patients unexpectedly referred from nurse-administered sedation levels of care to the anesthesia team–administered level of care. If true, practice efficiency may have improved. They report that their practice change allowed a 13% increase in complex endoscopy volume, presumably without expanding the number of rooms or providers needed for this increased procedure number. In addition, the authors found that sedation or anesthesia-related problems in patients who received anesthesia team–administered sedation or anesthesia were infrequent and, when present, readily corrected. They report that these patients experienced a 75% reduction in the frequency of sedation complications compared with patients in the historical nurse-administered sedation cohort. Unfortunately, the veracity of this very significant reduction in complications is not clear and may be inaccurate because of the retrospective approach used to assess the reported outcomes. Importantly, though, these problems in either cohort of patients did not appear to contribute meaningfully to the overall morbidity or mortality frequency in their patient population. These are the useful results of this report that will help readers as they consider practice models in their own institutions for patients undergoing complex GI endoscopic procedures.

In summary, Guimaraes et al.4 have offered a report that supports the benefit of anesthesia team–administered sedation or anesthesia for patients undergoing complex, (mostly) upper GI endoscopic procedures. They do not address the cost-effectiveness of the use of this practice model. Further studies, especially a high quality prospective, randomized trial of these 2 sedation/anesthesia practice models, are needed. When done, we hope that they evaluate not only the outcomes of the 2 practice models but also their cost-effectiveness. As expenses associated with GI endoscopy care escalate, this information is vital to facilitate practice decisions.

Back to Top | Article Outline


Name: Mary Ellen Warner, MD.

Contribution: This author authored the editorial text.

Attestation: Mary Ellen Warner approved the final manuscript.

Name: Mark A. Warner, MD.

Contribution: This author coauthored the editorial text.

Attestation: Mark A. Warner approved the final manuscript.

This manuscript was handled by: Sorin J. Brull, MD, FCARCSI (Hon).

Back to Top | Article Outline


1. American Society of Anesthesiologists Task Force on Sedation and Analgesia by Non-Anesthesiologists. . Practice guidelines for sedation and analgesia by non-anesthesiologists. Anesthesiology. 2002;96:1004–17
2. American Society from Gastrointestinal Endoscopy Standards of Practice Committee. . Guidelines, sedation, and anesthesia in GI endoscopy. Gastrointest Endosc. 2008;68:826–36
3. Centers. for Medicare & Medicaid Services (CMS). Clarification of the Interpretive Guidelines for the Anesthesia Services Condition of Participation, and Revised Hospital Anesthesia Services Conditions of Participation. State Operations Manual (SOM) Appendix A, Section 482.52. CMS publication no. 100–07, transmittal 59, effective date May 21, 2010. Washington, DC: Department of Health and Human Services, Center for Medicare and Medicaid Services; 2010. Available at Accessed June 13, 2014
4. Guimaraes ES, Campbell EJ, Richter JM. The safety of nurse-administered procedural sedation compared to anesthesia care in a historical cohort of advanced endoscopy patients. Anesth Analg. 2014;119:349–56
© 2014 International Anesthesia Research Society