Overlapping surgery is safe for most patients, but use with caution in those at high risk, study finds

The practice of doctors performing overlapping surgeries is safe for most patients, but high-risk patients might be the exception, a new study found.

A large study published in JAMA found that for adult patients undergoing common operations, overlapping surgery was not significantly associated with differences in in-hospital deaths or post-operative complications. However, overlapping surgeries did result in increased lengths of those surgeries by an average of 30 minutes.

And the research found that a subset of patients considered at high risk might be bad candidates for overlapping surgery, which put them at higher risk of death and post-operative complications such as infections, pneumonia or heart attack.

Unlike prior studies that looked at the safety of overlapping surgery and focused on a single institution or a single type of operation, researchers examined the results of 66,430 operations—of which 8,224 were overlapping—which took place at eight medical centers over an eight-year period and included common surgeries such as total knee or hip arthroplasty, spine surgery, coronary artery bypass graft surgery and craniotomy.

The study differentiated between overlapping surgery, in which more than one procedure performed by the same primary surgeon is scheduled so the start time of one overlaps with the end time of another, and concurrent surgery, when critical parts of operations occur during the same time and the attending surgeon is going back and forth between procedures.

Research has focused on the safety of double-booking surgery after the topic landed in the national spotlight several years ago.

The practice came into the public eye when the Boston Globe’s Spotlight team first reported concurrent surgeries were happening at Massachusetts General Hospital in Boston and other U.S. teaching hospitals. In 2016, a U.S. Senate committee investigated the practice, which is common at 47 hospitals across the country, and released a report urging hospitals to prohibit the practice of allowing one surgeon to manage two operations where critical parts occur at the same time.

The American College of Surgeons updated its guidelines in 2016, saying that juggling "critical" parts of surgery was "inappropriate" and requiring surgeons to notify patients when they will be conducting multiple simultaneous procedures.

The new JAMA study suggests overlapping surgery may not be appropriate for certain high-risk groups of patients. Researchers found that in high-risk patients, surgical overlapping resulted in slightly higher death rates—5.8% in overlapping surgeries compared with 4.7% for patients in non-overlapping cases. Results were similar for complication rates, which were 29.2% in high-risk patients in overlapping surgeries, compared to 27% for patients whose procedure was not overlapping.

RELATED: Report—Swedish Health surgeons performed concurrent surgeries without patients' knowledge

“Overall, the study findings suggest that overlapping surgery is likely to be a safe practice for most patients, but the exploratory analyses do suggest potential areas for concern and further investigation,” the researchers wrote.

In an accompanying editor’s note, Edward H. Livingston, M.D., JAMA’s deputy editor, said the study shows that overlapping surgery, which is essential for training surgical residents, is generally safe. “This work appealed to me because it answered an important, unresolved question: Is surgery safe as practiced in academic environments that balance the needs of safe patient care with those required to train the next generation of surgeons? The answer appears to be yes,” he wrote. But he noted the study does not address the risks associated with concurrent surgery, in which the attending surgeon is not present during a part of the operation that is considered critical.

Experts have advised that if practicing overlapping surgery, doctors must fully inform patients about scheduling practices well ahead of the surgery. They should disclose the likelihood that the operation will involve an overlap, and a description of who will perform which parts of the operation and their qualifications.