SAN DIEGO – Monitored anesthesia care (MAC) for outpatient endoscopy is on the rise in the United States, presumably because of financial incentives for fee-for-service gastroenterology (GI) practices. However, a new study found that use of MAC is increasing in Veteran’s Health Administration (VHA) facilities, an environment free of financial incentives.
The increase in VHA hospitals is much smaller than in the country as a whole, but the study suggests that there are additional drivers for use of MAC that need to be more fully explored.
Over the past two decades, the rate of MAC use for outpatient endoscopy in fee-for-service practices has increased by at least 30%. Over the study period, the rate of MAC use for endoscopy procedures doubled in VHA facilities from 5.7% in 2000 to 11.1% in 2013, with a larger proportion of increase between 2011 and 2013.
“The increase in MAC use in fee-for-service practices is thought to be driven by financial gain. With an anesthesiologist on hand for an endoscopy procedure, the practice can bill double [duplicative billing with separate billing codes], essentially getting double reimbursement. The VHA has little incentive to increase use of MAC for financial gain. We wanted to study use of MAC in the VHA environment to determine if there are other factors involved,” explained Dr. Megan A. Adams of the University of Michigan, Ann Arbor.
Dr. Megan A. Adams
In an interview, Dr. Adams explained that American Society for Gastrointestinal Endoscopy guidelines for MAC use are relatively broad and diffuse. They state that MAC should be considered for patients with anticipated intolerance to standard sedatives, certain cardiopulmonary morbidities, and the potential for airway compromise.
“These will need to be more specific in the future,” she said.
The retrospective cohort study she reported on at the annual Digestive Disease Week was based on national VHA data from more than 1,700 sites of care, with about 300,000 endoscopies performed each year.
“A large variation of MAC use was observed across study facilities, particularly in the later years of the study period,” Dr. Adams explained.
The investigators developed a model based on 122 VHA facilities, 2.1 million patient encounters, and the time of event to analyze patient-level and provider-level predictors of MAC using multilevel random effects logistical regression analysis.
Patient-level factors associated with the increased use of MAC included female gender (35% increase), body mass index greater than 35 kg/m2 (20% increase), obstructive sleep apnea (50% increase), opioid use (17% increase), and benzodiazepine use (13%). Charlson comorbidity scores were associated with a significant increase, compared with healthy patients, with a score of 3 having a 30% increased likelihood of MAC use.
Provider-level predictors of MAC use were related to facilities. Outside of the GI endoscopy suite, endoscopy procedures were about four times more likely to be performed with MAC, and surgeons were about 50% more likely to use MAC.
“The variation in MAC use is largely explained by facility factors. Potential facility factors could be academic versus nonacademic setting, differences in how sites triage care, and differences in local policy. Patient-level factors were relatively weak influences. We will need to explore provider-level [facility] factors more fully to understand the specifics,” she said.
“We will need to align incentives to promote more appropriate use of MAC tailored to patient factors,” Dr. Adams said.
“Payment reforms are looming. CMS will probably remove duplicative reimbursement for MAC. The country will follow CMS. This will affect the financial drivers of MAC, but not necessarily the nonfinancial drivers,” she predicted.
Dr. Adams had no financial disclosures.