Although there have been some concerns that patients might suffer from having such doctors in training -- medical school graduates known as residents -- operate on them, the findings show that health problems and death related to surgery were unrelated to the seniority of the surgeon.

"The important thing is to train future surgeons and to make it safe during the process, and it looks like (the hospital in the study) has figured out how to do that," said Dr. Matthew Hutter, a surgeon and the director of the Codman Center for Clinical Effectiveness in Surgery at the Massachusetts General Hospital, who was not involved in this study.

Previous research has looked at the impact of the so-called "July effect" -- the time of year when doctors-in-training begin their residencies.

The fear has been that being admitted to the hospital in July could mean worse care by an inexperienced physician, and while some studies have found evidence for that, others have not (see Reuters Health report of September 14, 2011).

Patients sometimes ask not to be operated on by a resident, said Dr. Leon Graat, a resident surgeon at St. Elisabeth Hospital in Tilberg, The Netherlands, who led the study.

"It made me wonder if residents do underperform or if it is only in the mind of the patient that only experienced doctors can take good care of them," Graat told Reuters Health by email.

'SHOULD HAVE NO HESITATION'

To answer the question, he and his colleagues looked back on the medical records of all patients who had their appendices removed at his hospital between 2000 and 2009.

Appendectomies are useful to study because it is one of the first surgeries performed by residents, Graat said, and at his hospital appendectomies are usually assigned to residents unless one is not available. Surgeons remove more than 320,000 per year in the U.S., according Graat and his co-authors.

Of the more than 1,400 patients included in the study, 23 percent had their appendices removed by a staff surgeon, also called an attending, a doctor who has finished all his or her training.

The rest of the surgeries were performed by residents; half of whom were supervised by a staff surgeon, and the other half were done independently.

Graat said these numbers are probably typical of other Dutch teaching hospitals.

His group found that the number of patients who had a complication related to the surgery, such as an infection, and the number who were readmitted to the hospital were the same for unsupervised residents, supervised residents and attending surgeons.

Just four patients died, two after surgery by an unsupervised resident and one after surgery by each of the other groups, and the authors considered death to be equally likely during an operation by each type of doctor.

"Although more research is needed to further analyze the relation between patient safety and resident teaching, patients should have no hesitation when they are being treated by residents," Graat said.

'GRADED AUTONOMY'

Graat said he believes the findings are a reflection of residents' skills.

"I do believe that residents are just as capable as experienced surgeons because the resident has been trained to perform this operation by an experienced surgeon," he said.

Graat said that surgeons only trust unsupervised operations with residents who have clearly demonstrated their competence and who will call for back up if the surgery becomes too complicated.

"We can conclude that in a teaching hospital residents obviously know their limitations and that surgeons also know the limitations of their residents and therefore can determine whether the resident can perform the operation unsupervised," Graat said.

It's possible that the results reflect some form of cherry picking -- that attending surgeons might have jumped in on the more complicated patients, leaving the simpler cases to residents.

Graat's team tried to account for the severity of each case, and they found that the number of burst or damaged appendices, which would make a surgery more difficult, were the same for each group of doctors.

Hutter said it's still difficult to completely account for residents' potentially getting the easier cases because the patients were not randomly assigned to each physician.

"The attending surgeon probably has a lot of information passed on to them to decide whether to do the surgery or pass it on to a resident," he said.

But the results show that this system seems to be working in terms of patient safety.

Hutter said giving residents "graded autonomy" -- meaning, greater levels of responsibility and independence as they become more skilled -- is important for training them.

"The goal is to train safe and effective surgeons...and it appears what they're doing is safe -- having surgeons involved in some cases, not involved in others," Hutter told Reuters Health.

Hutter said it's hard to say whether the rate of surgeries performed by residents in this study is similar in other hospitals, because teaching centers vary widely in how much supervision they require.

SOURCE: bit.ly/GTmR4w Annals of Surgery, April 2012.

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