Surgical Outcomes

The Surgical Outcomes Program in the Mayo Clinic Robert D. and Patrician E. Kern Center for the Science of Health Care Delivery is a collaboration of surgeons, anesthesiologists, scientists and allied health staff whose goal is to improve the quality of surgical patient care at Mayo Clinic and worldwide.

Invasive surgical procedures are complex and may lead to complications and adverse events, which negatively affect patients and contribute significantly to overall health care costs.

Using Mayo Clinic institutional data and multiple sources of multicenter and national data, the Surgical Outcomes Program focuses on building evidence to inform the practice of surgery and improve its safety, efficiency and quality as well as the experiences of patients undergoing surgery.


Opioid prescription guidelines

To address the ongoing opioid crisis in the United States, researchers in the Surgical Outcomes Program have studied prescribing practices at Mayo Clinic since 2016 and led an effort to create evidence-based guidelines in every surgical department across all Mayo Clinic campuses.

The initiative brought together a diverse group from across Mayo Clinic ― including physicians, nurses, psychologists, pharmacists, research scientists, engineers, government advocates, administrators and more.

Early on, the research team discovered a wide variation in opioid prescribing habits within departments and across Mayo Clinic. In response, the team developed, implemented and refined guidelines across the enterprise based on individual patient need and type of surgery or procedure.

While the project team continues to refine its recommendations based on new research, most departments have already shown a significant drop in opioid prescriptions. For example, the Mayo Clinic Department of Orthopedic Surgery has transformed its prescribing practices, reducing the opioids prescribed for patients undergoing hip or knee replacement surgeries by 48%. In the Department of Urology, opioid prescriptions decreased for all 21 types of surgery studied. During that time, prescription refills also decreased, meaning patient pain management was not affected.

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COVID-19 in the hospital setting

In a study conducted between May 15 and June 15, 2020, at the Mayo Clinic campus in Rochester, Minnesota, the Surgical Outcomes Program team monitored COVID-19 rates in patients who were hospitalized for care not related to coronavirus infection.

The study included PCR tests for COVID-19 to see if the virus was present and active in the patients, and serology tests to see if the patients had antibodies from a previous COVID-19 infection. Of the 1,310 patients included, none tested positive for the virus. Furthermore, of the 445 patients who followed up with testing between 14 and 21 days after leaving the hospital, zero tested positive.

At the time, the hospitals were between 62% and 77% full and all rooms were converted to single-patient occupancy. Mayo Clinic also strictly followed other pandemic guidelines, including universal masking for staff and visitors, eye protection for staff, a limit of one visitor per patient, and social distancing in all common areas.

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Same-day discharge after colectomy

Researchers in the Surgical Outcomes Program studied 36,526 patients who had undergone colectomies, 906 of whom were discharged from the hospital on the same day or after a one-day stay.

The project team found that patients who were discharged earlier tended to have shorter-duration operations and fewer pre-surgical factors that indicated potential complications. For those patients, rates of readmission and complications were equivalent and in some cases lower than those who stayed for three days per the standard of care.

Thus, the discharge day was not associated with an increased risk and was not a contributing factor for readmission or complications such as anastomotic leak or lack of normal muscle contraction (ileus). The researchers concluded that in carefully selected patients, same-day discharge is safe, could save costs for the patients and could increase access for other patients.

The research was led by Nicholas P. McKenna, M.D., a Surgical Outcomes Research Fellow, and senior author David W. Larson, M.D, M.B.A.

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Blood test for pancreatic cancer

A simple blood test to determine whether the level of carbohydrate antigen (CA) 19-9 is elevated in patients who have been newly diagnosed with pancreatic cancer can have a profound effect on survival — yet many institutions are not using the test.

The Surgical Outcomes Program investigated the prevalence of test use across the U.S. and determined the real value of the test for patients. Using the National Cancer Data Base, researchers analyzed outcomes for more than 113,000 patients and found that less than 25% of patients received the CA 19-9 test. Concurrently, the researchers showed that patients with elevated CA 19-9 levels tended to have worse outcomes than others at the same stage of cancer. They also saw that the elevated tumor marker's negative effect on survival was most pronounced in patients diagnosed at an early stage.

The team then looked at when chemotherapy was given to patients and determined that for patients with elevated levels of the CA 19-9 tumor marker, the best outcomes — that is, longest survival rates — occurred if chemotherapy was given before the surgery. The outcomes of patients with elevated and nonelevated levels then were the same.

While the CA 19-9 test for patients with pancreatic cancer has been a standard part of care at Mayo Clinic for years, the researchers noted that the test isn't widely used across the country. More widespread use of the simple test and understanding the mitigating effect of pre-surgical chemotherapy for these patients could save many lives.

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Surgical site infection after craniotomy

Patients with intracranial neoplasms are at higher risk of surgical site infections after craniotomies than are patients undergoing the surgery for other reasons. In this study, the Surgical Outcomes Program team sought to identify patient risk factors associated with the development of surgical site infections and to understand the impact of these infections on resource utilization, including rates of return to the operating room and length of stay.

The researchers analyzed prospectively collected data in the National Surgery Quality Improvement Program (NSQIP) database, which gave this study a larger sample size than has been afforded to other surgical site infection studies. The NSQIP data set is also a surgical registry. As a result, its level of clinical detail is superior to that of administrative data sets and allows researchers to achieve a level of resolution closer to that seen in single-institution studies.

This study identified patient risk factors that may assist health care providers' decision-making regarding patient risk stratification, timing of surgery or preoperative antibiotic prophylaxis for patients with intracranial neoplasms undergoing craniotomies.

Moreover, the research team found that the additional morbidity and resource use associated with surgical site infection — including increased rates of return to the operating room and length of stay — highlight the need for continued efforts to reduce these infections.

Additionally, this study highlights the importance of surgical site infection as a quality metric and should serve as a motivator for clinicians and researchers to continue exploring methods for reducing their occurrence.

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Real-time tissue analysis during surgery

A study by the Surgical Outcomes Program showed that frozen section analysis during breast cancer lumpectomies — which ensures surgeons remove all cancerous tissue while patients are still anesthetized — spares patients the need for a repeat lumpectomy within a month in about 96% of cases at Mayo Clinic in Rochester, Minnesota. Mayo's success rate is higher than the approximately 87% rate nationally.

These findings have significant implications for other types of surgery, patient satisfaction and cost of care. Additional research identified some of the financial impacts that widespread use of this process would have on health care costs, including potential savings as great as $90 million in the U.S.

Mayo Clinic remains one of the only U.S. medical centers to perform frozen section analysis, which was pioneered at Mayo more than 100 years ago and is used in a variety of surgeries.

Elizabeth B. Habermann, Ph.D., Robert D. and Patricia E. Kern Scientific Director for Surgical Outcomes Research, was senior author on the study.

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The Surgical Outcomes Program team has been instrumental in answering clinical questions, building the evidence base in health care delivery and contributing to the body of scientific knowledge.

The link below returns citations from PubMed, a service of the National Library of Medicine. PubMed is composed of references and abstracts from Medline, life science journals and online books. It includes publications authored by members of the Surgical Outcomes Program team.

Review publications from the Surgical Outcomes Program iin the Mayo Clinic Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery.


Elizabeth B. Habermann, Ph.D.

  • Robert D. and Patricia E. Kern Deputy Director of Research, Mayo Clinic Kern Center for the Science of Health Care Delivery
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