Anesthesiologist Involvement in Screening Colonoscopy: Temporal Trends and Cost Implications in the Medicare Population

Background & Aims: Colonoscopy is a recommended component of screening for colorectal cancer. We conducted a retrospective study of Medicare data to determine the frequency of anesthesiologist involvement and to identify patient and provider characteristics and cost implications associated with anesthesiologist involvement.

Methods: We used the linked Surveillance, Epidemiology, and End Results Medicare dataset to identify patients without cancer who received a screening colonoscopy examination from July 2001 through 2006 (n = 16,268). The outcome variable was anesthesiologist involvement, which was identified by searching Medicare claims. Logistic regression was used to explore the association between patient and provider characteristics and anesthesiologist involvement. Costs associated with the use of an anesthesiologist were derived based on a cost assessment by the Agency for Healthcare Research and Quality.

Results: Of the screening colonoscopies assessed, 17.2% involved an anesthesiologist. The screening colonoscopy rate more than doubled during the study period. The frequency of anesthesiologist involvement increased from 11.0% of screening colonoscopies in 2001 to 23.4% in 2006. Surgeons involved an anesthesiologist in 24.2% of colonoscopies, compared with 18.0% of gastroenterologists and 11.3% of primary care providers. The percentage of colonoscopies that involved an anesthesiologist varied among regions, ranging from 1.6% in San Francisco to 57.8% in New Jersey. Anesthesiologist involvement increased the cost by approximately 20% per screening colonoscopy.

Conclusions: An increase in the involvement of anesthesiologists has significantly increased the cost of screening colonoscopies. Studies are needed to assess the effects of anesthesiologists on risks and benefits of colonoscopy, to determine the most safe and cost-effective approaches.