Cover: Anesthesia Service Use During Outpatient Gastroenterology Procedures Continued to Increase from 2010 to 2013 and Potentially Discretionary Spending Remained High

Anesthesia Service Use During Outpatient Gastroenterology Procedures Continued to Increase from 2010 to 2013 and Potentially Discretionary Spending Remained High

Published in: American Journal of Gastroenterology, 2016

Posted on Jul 19, 2016

by Zachary Predmore, Xiaoyu Nie, Regan Main, Soeren Mattke, Harry H. Liu

Research Question

  1. Has the previously observed trend of increased anesthesia service for outpatient gastrointestinal procedures persisted in the period 2010 through 2013?


Previous studies have identified an increasing number of gastroenterology (GI) procedures using anesthesia services to provide sedation, with a majority of these services delivered to low-risk patients. The aim of this study was to update these trends with the most recent years of data.


We used Medicare and commercial claims data from 2010 to 2013 to identify GI procedures and anesthesia services based on CPT codes, which were linked together using patient identifiers and dates of service. We defined low-risk patients as those who were classified as ASA (American Society of Anesthesiologists) physical status class I or II. For those patients without an ASA class listed on the claim, we used a prediction algorithm to impute an ASA physical status.


Over 6.6 million patients in our sample had a GI procedure between 2010 and 2013. GI procedures involving anesthesia service accounted for 33.7% in 2010 and 47.6% in 2013 in Medicare patients, and 38.3% in 2010 and 53.0% in 2013 in commercially insured patients. Overall, as more patients used anesthesia services, total anesthesia service use in low-risk patients increased 14%, from 27,191 to 33,181 per million Medicare enrollees. Similarly, we observed a nearly identical uptick in commercially insured patients from 15,871 to 22,247 per million, an increase of almost 15%. During 2010–2013, spending associated with anesthesia services in low-risk patients increased from US$3.14 million to US$3.45 million per million Medicare enrollees and from US$7.69 million to US$10.66 million per million commercially insured patients.


During 2010 to 2013, anesthesia service use in GI procedures continued to increase and the proportion of these services rendered for low-risk patients remained high.

Key Findings

  • Most of the trends of increased anesthesia service use for gastrointestinal (GI) outpatient procedures, observed during the period 2003 to 2009, continued through 2013.
  • The proportion of patients receiving anesthesia services continued to rise.
  • Use of anesthesia services varied considerably by geographic region; in the 2010 to 2013 period, service use increased most in the South region.
  • A large proportion of anesthesia services were potentially administered to low-risk patients: nearly 60 percent of Medicare patients and more than 80 percent of those commercially insured.
  • The annual growth rate of total payments for potentially discretionary anesthesia services was much larger for commercially insured patients (11.5 percent) compared with Medicare patients (3.2 percent).
  • An estimated $1.5 billion was spent nationwide on potentially discretionary anesthesia services.
  • The new rule by the Centers for Medicare and Medicaid Services, which waives cost sharing for anesthesia service use during screening colonoscopies, may increase the use of anesthesia in low-risk patients.

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