Debates over which procedures and apnea patients are suitable for care in ASCs likely will continue. But recent research suggests that when patients are screened for OSA and evidence-based guidelines are followed, they can be managed safely in an ambulatory setting.1

“Most people with obstructive sleep apnea are undiagnosed. When dealing with a condition that will get exacerbated on general anesthesia and opioids, there are publications that talk about how these people might be at risk after surgery,” says Rebecca S. Twersky, MD, MPH, chief of anesthesia at Josie Robertson Surgery Center at the Memorial Sloan Kettering Cancer Center in New York City.

Surgery center leaders might worry about malpractice lawsuits if something goes wrong, she adds. “They’re concerned about this condition, and then it’s compounded with the short stay, so they’re doubly concerned about whether an OSA patient will stop breathing when he gets home or is in the recovery room,” Twersky explains.

From an anesthesiologist’s perspective, the patient might be sensitive to the effects of opioids and demonstrate obstructive breathing during surgery, or their oxygen saturation could drop in post-op. “There were examples of patients behind the drapes in recovery rooms. Everything was fine, and then someone pulls open the drapes, and the patient is dead because of the added effect of opioids in the post-op period,” Twersky says. “If you give someone a sedative, and they stop breathing [on your watch], it’s a problem.”

While opioids contribute to obstructive breathing, they are not the sole reason OSA patients are at risk. Sleep apnea patients also could be harmed by exposure to general anesthesia gases or another sedative, Twersky offers.

“In our study, we actually did look to see if there was any difference in the amount of opioids used in high-risk patients vs. low-risk patients,” she says. “We didn’t see any difference in the amount of opioids they were exposed to.” Doctors need to be mindful of patients’ underlying diagnosis and then titrate the amount of opioids accordingly, Twersky adds.

Each patient in the study was screened for OSA risk, using the STOP-BANG tool. (See cover story for more about the tool.) Then, researchers divided the patients into categories of low and moderate risk vs. high risk and patients diagnosed with the condition.1 “After identifying patients using the scoring tool, we’d know that if they were low risk, they’d probably be fine,” Twersky says. “But if they’re moderate or high risk, can we give them general anesthesia, and what do we do with a patient who looks like high risk?”

One step is to tell clinicians before surgery about any patients diagnosed with OSA or who are at high risk of having the condition.1 Research suggests that identifying potential OSA patients is crucial to positive outcomes.

“Our study addresses that in a big way,” Twersky says. “We concluded that patients who are properly screened and identified as high risk of OSA or were diagnosed with OSA were not at a greater risk for complications and did not have a greater rate of being transferred to an inpatient facility.”

The key is to provide pathways of management for OSA patients. Protocols could look like this:

  • Screen all patients for OSA;
  • Identify patients at high risk for OSA, cardiac disease, and other conditions;
  • Make positive airway pressure devices available;
  • Put trained nursing staff or a respiratory therapist in place;
  • If worried, transfer the patient to an inpatient setting.

Following the above protocol works and can reduce transfer rates. “The transfer rate wasn’t any greater for this index population when compared with non-OSA patients, and there was no greater readmission rate,” Twersky reports.

When patients are identified as at risk, their surgery care management can adjust to prevent adverse events, and clinicians can make changes in patient instructions and medication. For instance, a surgery center might want to direct patients who are diagnosed with OSA to use a CPAP machine. For some surgery centers, it makes sense to purchase these devices to use with high-risk OSA patients, Twersky notes.

“If someone has known sleep apnea, they are often given a CPAP device or breathing device to help them improve the respiratory and cardiovascular complications,” she says. “The devices make it easier for the patient to breathe and not have a drop in oxygen saturation.” Those are the easier patients to manage, Twersky says. For example, a surgery center can ask these patients to bring their CPAP device on the day of surgery. Once the device is examined for electrical integrity, and if it is approved, the patient could use his or her own machine in the postoperative period.1

“Patients who come in with a diagnosis are the minority,” Twersky notes. “Most patients either admit to the pre-op nurse that they do snore, and most come in without a diagnosis.”

It is not possible to cancel all patients with sleep apnea, so surgery centers need to follow best practices in identifying and managing these patients. In the study by Twersky and colleagues, all patients with moderate or high risk of OSA were assessed by a respiratory therapist postoperatively. This therapist made note of any problems, such as repeated desaturations of less than 90% oxygen saturation or obstruction (apnea or snoring) lasting 20 seconds. If the therapist believed there was a need for a CPAP machine, bi-level positive airway pressure, or continued mechanical ventilation, this was recorded.1

Finally, it is important to be mindful of drugs given to OSA patients. Twersky recommends watching these patients postoperatively and to see if there’s any obstructive breathing that might be associated with medications they are taking.


  1. Szeto B, et al. Outcomes and safety among patients with obstructive sleep apnea undergoing cancer surgery procedures in a freestanding ambulatory surgical facility. Anesth Analg 2019; Apr 8. doi: 10.1213/ANE.0000000000004111. [Epub ahead of print].