Skip to Main Content

Tens of millions of Americans undergo surgery each year. They expect their surgeon to be in the operating room for the entire procedure. That’s not always the case — the surgeon may have two operations scheduled at the same time.

Although the notion of a surgeon being in two places at once may seem worrisome, our new research suggests that overlapping surgery is generally a safe practice. There are some groups, however, for which it may not be.


Operating rooms are costly to run and wait times for skilled surgeons can be long. The pressure to be more efficient and treat more patients can lead surgeons to schedule procedures in more than one operating room at a time. This practice is known as overlapping surgery. When doing this, surgeons typically delegate the routine parts of an operation, like suturing an incision, to physician assistants or surgical trainees, while they perform the critical parts of an overlapping case in a different operating room.

Defining what is “critical” is at a surgeon’s discretion and complications can arise even during the noncritical parts of an operation. That’s why concurrent surgery — an extreme form of overlapping surgery in which a surgeon may be absent during critical portions of an operation — has already been deemed inappropriate by professional societies and insurers.

Concerns about the safety of overlapping and concurrent surgery made national headlines in 2015 with a Boston Globe Spotlight investigation of the practice at Massachusetts General Hospital, a large Boston teaching hospital. It was followed shortly by news of similar practices and safety concerns at Swedish Health, a large Seattle hospital system. The Senate Finance Committee has since held hearings on the subject and issued a report highlighting several concerns about the practice.


Evidence on the safety of overlapping surgery has been mixed. Several studies have shown that there aren’t more complications among patients whose surgeons are performing overlapping surgery, but these studies have focused on single types of procedures or have been conducted in single institutions. Although one study found increased complications for patients whose hip replacements were being performed as overlapping surgeries, no large-scale evidence exists on whether overlapping surgery is generally safe for patients.

In a study published Tuesday in the Journal of the American Medical Association, we explored the safety of overlapping surgery among nearly 66,000 individuals undergoing common surgeries like joint replacement, coronary artery bypass graft surgery, spine surgery, and craniotomy (an operation to open part of the skull to expose the brain) at one of eight institutions included in the Multicenter Perioperative Outcomes Group registry. For each of these types of surgeries, we compared a given surgeon’s overlapping operations against non-overlapping operations he or she performed.

Nearly 12 percent of the operations had some overlap with another case. For the majority of overlapping surgeries, we found no increase in deaths or overall complications (a combination of both major and minor complications that can occur during surgery) compared to surgeries that did not overlap. That said, a subset of complications — major complications such as stroke and heart attack — were slightly higher.

We also found small increases in deaths and complications for overlapping surgeries involving coronary artery bypass grafting and those involving high-risk patients, meaning individuals predicted to have a high risk of dying or developing post-operative complications based on their age and pre-existing health conditions. In both of these groups, small errors in surgical care could have harmful effects. Although the increases in deaths and complications in these two groups were small, they deserve serious further investigation — including efforts to replicate our results in other data.

Although our research indicates that overlapping surgery is common and that the practice is likely safe for the vast majority of people undergoing surgery, many people may still view this practice with distrust, or believe that it falls below their expectations for their surgeon’s involvement in their care. We believe it is incumbent on surgeons who perform overlapping surgery to make sure their patients are informed of the practice and its general safety. They also need to identify instances in which overlapping surgery may be unsafe and potentially avoid the practice in these cases.

A survey of almost 1,500 people found that while only 31 percent approved of overlapping surgery, that number increased to 65 percent for low-risk procedures — precisely the situation in which our study suggests that overlapping surgery should be safe.

The possible risks of overlapping surgery among high-risk patients and those undergoing coronary artery bypass grafting must be weighed against its potential benefits. By making it possible for a surgeon to simultaneously perform several procedures, overlapping surgery can increase access to that surgeon’s expertise. That reduces wait times for surgery and expands the number of people who can be treated. Overlapping surgery may also improve the efficiency of operating rooms, which lowers costs, and may provide surgical trainees opportunities to hone their skills in an independent manner.

Although overlapping surgery appears safe for the majority of patients, it may not be for all of them. Ensuring that the benefits of the practice don’t come at the cost of patient safety is essential.

Eric C. Sun, M.D., is an assistant professor of anesthesiology and perioperative and pain medicine at Stanford University Medical Center. Anupam B. Jena, M.D., is a physician at Massachusetts General Hospital and an associate professor of health care policy and medicine at Harvard Medical School. He has received consulting fees unrelated to this work from Pfizer, Hill Rom Services, Bristol-Myers Squibb, Novartis, Amgen, Eli Lilly, Vertex Pharmaceuticals, AstraZeneca, Celgene, Tesaro, Sanofi Aventis, Biogen, Precision Health Economics, and Analysis Group.

Comments are closed.