Nearly 9% of all routine outpatient colonoscopies that were performed in 1 year in a nationally representative sample of Medicare beneficiaries used anesthesia assistance – an anesthesiologist or nurse-anesthetist – to administer deep sedation using propofol.
The American Society for Gastrointestinal Endoscopy recommends against anesthesia assistance for such average-risk patients because it isn’t warranted and is cost-prohibitive. Nevertheless, in this retrospective cohort study using a nationally representative sample of 328,177 Medicare patients who underwent routine outpatient colonoscopy during 2003, anesthesia assistance was used in 8.7% of the procedures. This included 8.2% of procedures done in patients who had no comorbidities (Gastroenterology 2012 Oct. 29 [doi: 10.1053/j.gastro.2012.10.038]).
The researchers, led by Dr. Jason A. Dominitz of the VA Puget Sound Health Care System in Seattle, found that the use of anesthesia assistance varied dramatically by geographic location and by the endoscopist’s specialty. A very small proportion of the endoscopists in this study, 4.5%, accounted for more than 40% of the procedures performed using anesthesia assistance.
"Those endoscopists with very high rates of anesthesia assistance overwhelmingly practiced in an urban setting (95%) and were disproportionately represented by gastroenterologists (76%) and colorectal surgeons (10%)," as compared with general surgeons, internists, family physicians, or others.
"This practice has enormous economic implications for society, as the use of an anesthesia provider adds a considerable cost to each procedure and is at variance with recommendations from professional societies. In 2003, charges to Medicare for sedation by anesthesia professionals during colonoscopy were nearly $80 million," said Dr. Dominitz, who is also with the division of gastroenterology at the University of Washington, Seattle, and his associates.
"If the projected growth in the use of anesthesia assistance does reach 53% by 2015, the total national expenditure for this service could range from approximately $800 million to $3.8 billion annually," they noted.
The investigators studied this issue because the use of propofol for deep sedation during routine colonoscopies has increased markedly.
The study sample included only colonoscopies performed in hospital outpatient clinics, ambulatory surgery centers, private offices, and other outpatient settings by 18,578 physicians.
Among the study’s findings:
• Use of anesthesia assistance didn’t alter the rate of detection of colonic polyps or the rate of complications such as GI bleeding, perforation, and hospital/ED visits within 30 days.
• Use of anesthesia assistance varied widely among the states, and even between states that bordered each other. The lowest rates of use were in Montana (0.1%) and South Dakota (0.2%); the highest were in New Jersey (48.1%), New York (27.9%), and Nevada (26.0%). "This variation is most likely attributable to variation in reimbursement practices by different carriers," Dr. Dominitz and his associates said.
• Younger endoscopists and those with fewer years in practice were more likely than older endoscopists and those with more years in practice to use anesthesia assistance.
• The volume of patients seen by the endoscopist did not correlate with use of anesthesia assistance.
• More than 80% of general surgeons, internists, and family physicians performed no colonoscopies with anesthesia assistance.
• Anesthesia assistance was more frequently used in black than in white patients, perhaps because of the very high rates of use in urban settings, where there is more racial diversity. Urban patients were more than twice as likely to receive anesthesia assistance as rural patients.
In a sensitivity analysis excluding patients with comorbidities, the findings confirmed those of the main analysis.
This study was not designed to determine the reasons for these variations in the use of anesthesia assistance. However, the researchers speculated that because propofol has a faster onset and more rapid recovery time than opiates and benzodiazepines, it improves practice efficiency, allowing more procedures to be performed per day.
In addition, employing anesthesia providers can generate an extra income stream for endoscopy practices. And if endoscopists who practice outside of hospitals already employ anesthesia providers for higher-risk or hard-to-sedate patients, "it may be prudent business practice to utilize these providers for more routine cases as well," Dr. Dominitz and his colleagues said.
This study was supported by the American College of Gastroenterology, the American Society for Gastrointestinal Endoscopy, and the VA Puget Sound Health Care System. No financial conflicts of interest were reported.
