Ambulatory surgery centers (ASCs) are outpatient facilities that offer surgical procedures to patients at reduced costs, often with greater scheduling flexibility than hospitals. Also known as same-day surgery centers, these facilities allow patients to undergo minor surgical procedures during the day and recover at home rather than remain at a hospital for overnight observation.
While this model has advantages for patients seeking routine procedures, it can pose serious safety risks for patients seeking more complicated procedures like joint replacements or upper spine surgery. This is where the lure of a surgery center can become its greatest liability. A 2018 investigative report from Kaiser Health News, publicized by USA Today, revealed that more than 260 patients have died due to procedure complications at ASCs since 2013, primarily from “routine procedures” like tonsillectomies or colonoscopies. At least 10 percent of these patients died within 24 hours of being released from an ASC.
According to Definitive Healthcare data, ASCs reported performing more than 9 million Medicare procedures in 2016 (resulting in more than $5 billion in charges) and 7.7 million Medicare procedures in 2017 (resulting in $4.7 billion in charges).
Most surgery center procedures are performed without any difficulty, and physicians have access to the proper training and specialized equipment. ASCs may not have the tools necessary in a medical emergency due to high medical device costs or lack of specialized training. According to the study, hospital providers are more likely than surgery center providers to have experience with trauma patients and emergency measures.
ASCs do not legally have the same staffing and emergency equipment requirements as hospitals, which the Kaiser investigative report indicated could lead to higher patient risk in life-threatening situations. In thousands of such cases, the Kaiser Health News discovered that ASC personnel had to call 911 for an emergency hospital transfer. Currently, Medicare requires surgery centers to align with a local hospital to transport patients in an emergency, but this could mean a 15-mile journey or longer in rural areas. Even in an urban setting, 30 minutes or more can pass between calling 911 and patient arrival at an emergency department—which can be too late to save a patient.
Top 10 Surgery Centers with Highest Hospital Transfer Rate
Surgery Center Name
Hospital Transfer Rate
# Operating Rooms
Total Medicare Charges
Atlanta Endoscopy Center Ltd., GA
Advanced Eye Surgery Center, CA
Headache and Pain Center
Coronado Surgery Center
Cardiovascular Outpatient Center of SW Louisiana
Heart and Vascular Institute
The Surgical Institute of Michigan
Specialty Surgical Center
Highline South Ambulatory Surgery Center
Midamerica Spine Center
Fig 1 Data from Definitive Healthcare based on self-reported data from 2017 (most recent reporting year).
The nature of an outpatient surgery means that a patient may be sent home too soon after a procedure without proper observation. Many surgery centers keep regular business hours unlike hospitals, which are open 24-hours. Patients undergoing procedures toward the end of the day may not be monitored for long enough to determine whether it is truly safe to discharge them. Kaiser Health News cites several cases in which patients were found unresponsive upon arriving home.
Though surgery centers do not have the same equipment and training requirements as hospitals, they still must follow strict patient safety guidelines. According to the study, since 2015, Medicare health inspectors found more than 230 lapses in in rescue equipment or training at ASCs across the U.S., with the potential to jeopardize patient health and safety. This does not mean that surgery centers are inherently less safe than hospitals. In fact, several studieshave shown that ASCs are just as safe for patients as hospitals and other inpatient facilities, even for procedures like upper spine surgery.
4 Upper Spinal Surgery Procedures by Medicare Charges
Name of Procedure
Facility with Highest Procedure Charges
Procedure Charges at that Facility
Neck spine fuse & remove c2 segment
Mayfield Spine Surgery Center
Neck spine fusion
Santa Rosa Ambulatory Surgical Center
Artificial cervical discectomy
Monterey Peninsula Surgery Center
Neck spine disc surgery
Midwest Surgery Center
Fig 2 According to Definitive Healthcare's 2017 Medicare procedure claims analytics by provider, in the Surgery Centers platform
Not all surgery centers in the U.S. are required to report to state or federal organizations. In New Jersey, for example, ASCs with only one operating room are not licensed by the state Department of Health, and therefore are not obligated to submit information on patient mortality or other events. These surgery centers are instead overseen by the licensing board for doctors.
The popularity of outpatient surgery centers with patients lies in their convenience and low costs, but physicians appreciate them for different reasons. Federal law allows physicians to refer patients to their own surgery centers, which offers much greater financial incentives than hospital referrals. Physicians who own surgery centers take a larger share of responsibility for patients, including risk assessment. However, experts worry that the financial incentives, particularly for complicated procedures like upper spinal surgery and joint replacements, will lead physicians to take on patients at a higher risk for complications simply for the money.
2019 OIG Report on ASCs
Most recently, the U.S. Department of Health and Human Services' Office of Inspector General (OIG) released a September 2019 data brief about ASCs, which found that infection control remains an issue at some ambulatory surgery centers. The report found that 77 percent of ASCs had least one violation and 25 percent had serious deficiencies. The report also found that dozens of states didn't meet survey requirements (many facilities went without any state survey for at least 6 years) or safety protocols, such as infection control or anesthesia administration. With ASCs now being approved for a growing number of complex surgeries, it's increasingly important for ASCs to place emphasis on routine ASC inspections and safety protocols.
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