Researchers with Northwell Health in New York studied younger patients who underwent a variety of procedures during the COVID-19 pandemic. They found patients fared well, suggesting the health system handled surgery decisions well.

  • The study authors targeted 3,762 patients who underwent ambulatory procedures. Of those, 53 were previously diagnosed with COVID-19, but recovered and tested negative at preprocedural testing. Of 3,709 asymptomatic patients, 37 tested positive during preprocedural testing; 21 patients delayed their procedures an average of 28.6 days until testing negative, while 16 underwent their procedures before testing negative because the operation was time-sensitive. There were no major complications or 30-day admissions in any asymptomatic patients.
  • These data suggest there may be no increased risk for an asymptomatic, COVID-19-positive patient to go forward with surgery, although more research is needed before surgeons can create evidence-based guidelines.
  • Although this study is limited by its size and retrospective nature, it stands out from previous similar investigations that focused on older patients undergoing much riskier procedures.

A new study of 3,762 ambulatory surgery patients revealed those who tested positive for COVID-19 and underwent a procedure after the positive test fared well.1

“We were curious because not much has been reported since opening ambulatory surgery centers and since every patient was tested for COVID-19,” says Christopher G. Larsen, MD, study co-author and an orthopedic surgery resident at Northwell Health. “We wanted to know the rate of people testing positive and how that was impacting their surgery experience.”

The average age of the patient population was younger than other cohorts in similar investigations (42 years). Further, similar investigations included patients who underwent high-risk procedures.2,3 Here, Larsen and colleagues studied patients who underwent a wide variety of procedures: general surgery; urology; orthopedic; OB/GYN; ear, nose, and throat; gastroenterology; and other procedures.

The goal was to determine whether positive COVID-19 tests resulted in delayed procedures and how long the delays lasted.

“We were able to get a list of all patients who had undergone ambulatory procedures and sorted out which had a record of a positive COVID-19 test,” Larsen says. “It was a smaller number than we initially expected.”

There were 37 patients who tested positive preprocedure for COVID-19, but were asymptomatic. Of these 37 patients, 21 delayed their procedures for an average of about 29 days until they tested negative. Sixteen of the COVID-19-positive patients underwent their procedures because of time sensitivity, but they experienced no major complications or 30-day readmissions.

“There are limited data on how COVID-19 patients do after surgery,” says Jessica M. Intravia, MD, study co-author and an orthopedic surgeon at the North Shore-Long Island Jewish Medical Center in New York. “In some studies, they showed that COVID patients did poorly in major surgeries.2,3 But in the ambulatory population, these patients are healthier and have less comorbidities, and we were not sure whether it was safe to proceed.”

Also, there is less guidance on when to proceed after a COVID-19 infection. Surgeons need to know whether it is safe to perform a procedure on an asymptomatic patient, or whether the procedure places them at higher risk. “How long is the minimum amount of time needed to delay surgery for those who test positive in presurgery testing?” Intravia adds.

For a low-risk outpatient procedure, these findings suggest proceeding as planned. “But there are limitations to our study, and more data are needed before this is regarded as a rule,” Larsen cautions.

For instance, this work included patients only from one health system. Further, the study was retrospective in nature, and the information used mostly was epidemiological. There also was no comparison group.

“It’s a first step that needs to be explored more thoroughly, but it’s a promising first step,” Intravia says. “More studies need to be performed, and there need to be firm guidelines. With asymptomatic patients who test positive, we’re treating them similar to other positive-test patients, but they’re a unique cohort that is very interesting.”

While trying to follow overarching pandemic guidelines issued by federal and state agencies, surgery centers and other healthcare systems often varied on how to handle COVID-19 patients. For example, Northwell Health limits the ability of ambulatory surgery settings to handle COVID-19-positive patients.

“The health system is trying to keep ambulatory surgery centers a low-risk environment,” Intravia explains. “I believe the decision depends on the patient’s overall health, risk factors, whether sedation is required. Our data suggest it could be of no increased risk — if they’re asymptomatic — to go forward with surgery.”

The study authors found no cases of patients who acquired COVID-19 because of their ambulatory surgery. There were three patients who tested negative for COVID-19 before surgery, but tested positive at an average of about 20 days after the procedure. Larsen believes because of the timing of their positive tests, these patients likely did not become infected during the surgery.

“We’re concluding the nosocomial rate of infection, patients who acquired COVID in house, is very low,” Larsen adds. “We can’t definitively say it’s none, because some patients may have tested positive outside of our health system. But it’s very low.” 


  1. Larsen CG, Bub CD, Schaffler BC, et al. The impact of confirmed coronavirus disease 2019 (COVID-19) infection on ambulatory procedures and associated delays in care for asymptomatic patients. Surgery 2021; Jan 20;S0039-6060(21)00022-2. doi: 10.1016/j.surg.2021.01.005. [Online ahead of print].
  2. Lei S, Jiang F, Su W, et al. Clinical characteristics and outcomes of patients undergoing surgeries during the incubation period of COVID-19 infection. EClinicalMedicine 2020;21:100331.
  3. Gruskay JA, Dvorzhinskiy A, Konnaris MA, et al. Universal testing for COVID-19 in essential orthopaedic surgery reveals a high percentage of asymptomatic infections. J Bone Joint Surg Am 2020;102:1379-1388.