Surgical Resident Independence Not Tied to Higher Post-Op Risks

Residents performing general surgery and hernia repairs can do so safely with varying degrees of supervision, restrospective cohort studies from the U.S. and Denmark showed, though such opportunities are becoming more scarce over time.

In a study of patients at Veterans Affairs (VA) facilities who underwent operations performed by residents, a propensity score-matched analysis of more than 22,000 surgeries found no differences in rates of complications or deaths when an attending surgeon scrubbed in to supervise compared with when the attending was not scrubbed in, reported Celsa Tonelli, DO, MS, of Loyola University Medical Center in Maywood, Illinois, and colleagues.

“These findings have relevance in the context of recent trends in U.S. health care where external forces continue to limit the opportunities that residents have to be independent,” they stated.

And in a second study from Denmark, primary groin and ventral hernia repairs carried similar reoperation risks regardless of if they were performed by supervised residents or non-resident specialists, according to researchers led by Camilla Christophersen, MS, of the University of Copenhagen.

Christophersen called the findings “reassuring,” in an email to MedPage Today, “since this means that residents can perform hernia repairs supervised, as part of their surgical training, without increased risk of reoperation due to recurrent hernia.”

The researchers for the two studies, both published in JAMA Surgery, stressed the importance of understanding how many procedures residents must perform to master surgical techniques.

Resident Independence at VA Training Facilities

The study from Tonelli’s group looked at 109,707 patients in the VA Surgical Quality Improvement Program database who underwent appendectomy, cholecystectomy, colectomy, inguinal or femoral hernia, or small-bowel resection from 2005 to 2021 at level 1 VA facilities.

Overall, 90% of the cases (n=98,526) had a scrubbed-in attending physician and 10% (n=11,181) had an attending present but not scrubbed in.

Investigators found that opportunities for resident independence in the VA training facilities decreased over time, with 44% of the procedures that involved attending surgeons who were not scrubbed in occurring from 2005-2009 and just 18% occurring from 2016-2021.

This was particularly true for appendectomies and hernia repairs, where the percentage of residents with a physician not scrubbed in decreased from 23% in 2005 to 7% in 2021 in the case of appendectomies and from 28% to 8%, respectively, for hernia repairs. The authors suggested that allowing for more resident independence could improve efficiency in operating rooms.

Unadjusted comparisons of the study’s main outcomes — postoperative complications, the severity of those complications, and mortality — showed better outcomes in cases where attendings were not scrubbed in, which “almost certainly reflects selection bias with cases of increasing complexity being done with higher levels of attending surgeon involvement,” the researchers noted. When the team adjusted for case complexity, they found the opposite to be true.

Multivariable analyses that adjusted for various factors — age, comorbidities, American Society of Anesthesiologists class, year and type of procedure, among other factors — found a higher likelihood of postoperative complications with:

• Older age: adjusted odds ratio (aOR) 1.19 (95% CI 1.16-1.22)
• Emergent cases: aOR 1.41 (95% CI 1.33-1.50)
• Resident independence: aOR 1.12 (95% CI 1.03-1.22)

Body mass index, open surgery, and certain comorbidities were also associated with higher odds of a complication, as were colectomy and small-bowel resections. But when each of the procedure types was modeled individually, “no notable association” was seen between resident independence and odds of complications.

Propensity matching of the 11,181 cases where the attending physician was not scrubbed in with an identical number of similar cases where the attending physician was, showed no significant differences in rates of surgical complications (7% vs 7%, P=0.41), severe complications (6% vs 6%, P=0.06), or death (1% vs 1%, P=0.47). Average operating time was sightly longer in cases where an attending surgeon was not scrubbed in (106 vs 104 minutes, P=0.009).

“Our findings identify little downside to allowing for what are judged, by experienced surgical attending physicians, to be reasonable degrees of resident autonomy,” concluded Tonelli and co-authors.

As it was a VA study, most patients were male (94%), and the average age was 61-63 years. Appendectomy (17%), inguinal hernia repairs (13%), and cholecystectomy (11%) were more often performed with attending surgeons who weren’t scrubbed in than small-bowel resections (6%) or colectomy (4%).

Complications evaluated for the study included infections, deep vein thrombosis, the need to return to the operating room, cardiac arrest, reintubation, dialysis, sepsis, and death.

Besides the selection bias the researchers tried to adjust for, Tonelli’s group noted a limited ability to both adjust for case complexity and assess the degree to which attending physicians offered guidance, scrubbed in or not.

Primary Groin and Ventral Hernia Repairs

In the study from Denmark, Christophersen and colleagues examined 31,683 cases of primary groin hernia repairs and 7,777 primary ventral hernia repairs performed from 2016 to 2021 by 868 supervised residents or general or gastrointestinal surgery specialists.

In unadjusted analyses, a slightly higher cumulative reoperation rate was seen following Lichtenstein repairs performed by the residents (4.8% vs 4.2%, P=0.048). But no significant differences in the adjusted risk of reoperation between supervised residents and non-resident specialists were observed for:

• Lichtenstein groin hernia repair: HR 1.26 (95% CI 0.99-1.59, P=0.06)
• Laparoscopic groin hernia repair: HR 1.01 (95% CI 0.73-1.40, P=0.95)
• Open ventral hernia repair: HR 0.89 (95% CI 0.61-1.29, P=0.54)
• Laparoscopic ventral hernia repair: HR 2.96 (95% CI 0.99-8.84, P=0.052)

Similar to the situation in the VA study, however, the researchers found that supervised residents only performed about 8% of laparoscopic groin and ventral hernia repairs.

“This is somewhat worrying,” Christophersen said, because “it appears that in our cohort only a few of the laparoscopic repairs were available for residents as part of their surgical training.”

In an accompanying commentary to the Denmark paper, Kyla Terhune, MD, MBA, of Vanderbilt University Medical Center in Nashville, Tennessee, noted that the actual level of supervision in these hernia repair cases remains “a missing data point.”

“This leads one to wonder whether a resident actually ‘did’ the case or whether the resident merely assisted,” she said. “One could potentially surmise the level of participation by using the year of training as a surrogate and continuous variable, but this was not included.”

Terhune also stressed the importance of transparency about resident involvement for patient care. “Transparency would help us acculturate and normalize supervision (and conversely progressive trainee autonomy) as a necessary part of medical and surgical education — one that is essential to the public,” she said.

Of the 33,424 patients included in the study, 84.7% were male. Researchers used data from the Danish Hernia Databases, capturing a period after a supervision variable was added, and the Danish Patient Safety Authority’s Online Register.

Study limitations, the team said, included the dichotomous supervision variable, the inability to adjust for body mass index and smoking status in analyses of groin hernia repairs, and the small number of hernia repairs performed by residents.