The New York Department of Health is still investigating the death of Joan Rivers, who died Thursday when she did not recover from cardiac arrest. Rivers, 81, was at Yorkville Endoscopy, an outpatient surgical center, for an elective procedure when she ceased breathing and her heart suddenly stopped. An autopsy proved inconclusive, the New York chief medical examiner’s office said Friday.

Rivers’ death is raising questions about how outpatient or ambulatory centers are accredited, and what regulations are in place to ensure patient safety. Each state health department oversees such facilities; some are part of hospitals and therefore regulated by the same organizations that oversee hospitals, while others are independently owned and operated by physicians.

Just under half of states, including New York, require that the latter centers receive accreditation from any of four organizations that set criteria for patient care and safety. The New York Department of Health lists three—Accreditation Association for Ambulatory Health Care, American Association for Accreditation of Ambulatory Surgery Facilities (AAAASF), and the Joint Commission.

As one of the organizations that accredits centers for which Medicare reimburses procedures, the AAAASF has a 162 page checklist of items, from requiring that a circulating nurse is in both the operating room and the recovery rooms, to board certification of surgeons performing the procedures and the presence of crash carts for resuscitating patients should complications occur. Centers also need to have an agreement with a nearby hospital to respond to any emergencies. Because of these criteria, says Dr. Geoffrey Keyes, president of AAAASF, death rates at ambulatory surgery centers that are accredited are similar to those at hospitals.

But if states do not require accreditation or licensure, then centers have to voluntarily apply for the status, which can cost $10,000 over three years and require regular inspections for compliance.

While the majority of ambulatory surgery centers are accredited by one of the four agencies perform the service in the U.S., the bulk of the smaller practices run by one or two physicians who perform surgical procedures at their offices are not. “One of the first questions a consumer should ask a surgeon is what environment do they intend to do the procedure, and whether that environment is accredited, whether it’s a hospital or outpatient center,” says Michael Kulczycki, executive director of the Ambulatory Care Accreditation Program of the Joint Commission.

If the facility is accredited, while it’s no guarantee that complications won’t occur, it’s a reassurance that a high level of patient safety and surgical standards are being met. “My personal belief is that with proactive risk and safety measures in place, and appropriate plans to mitigate emergencies, care in the ambulatory care environment would be as safe as care in an inpatient environment,” says Dr. Daniel Ross, field director for ambulatory programs at the Joint Commission.

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