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Too many routine preoperative tests performed before low-risk medical procedures


Guidelines recommend limiting medical tests before low-risk surgeries, however electrocardiograms and chest x-rays are still frequently performed, according to a study by researchers at the Institute for Clinical Evaluative Sciences (ICES) and Women’s College Hospital.

Evidence indicates that for patients undergoing low-risk surgery, routine testing does not improve outcomes and can actually lead to surgical delays, patient anxiety and other issues. The Choosing Wisely campaign, which started in the United States and spread to Canada in April 2014, aims to reduce unnecessary low value care practices by changing physician and patient attitudes.

The researchers looked at ICES data on more than 1.5 million patients aged 18 and over who underwent more than two million procedures such as endoscopy, opthalmologic surgery and low-risk surgery including knee and hernia repair in 137 institutions in Ontario from April 1, 2008 to March 31, 2013. Despite guidelines that do not recommend routine cardiac screening before low-risk procedures, the researchers found that electrocardiograms (ECGs) were performed before about one-third of surgeries. Preoperative testing was performed more frequently in older patients, with ECGs conducted 18.3 times more often in people over age 65 than in patients aged 18 to 25.

“Our study shows that rates of preoperative testing before low-risk procedures are higher than expected, with significant variation at the regional and institutional level across hospitals,” said Dr. Sacha Bhatia, cardiologist at Women’s College Hospital and a scientist at ICES.

The researchers found a 30-fold difference in rates of preoperative procedures between institutions with the lowest rates of preoperative tests and those with the highest rates.

Previous studies have looked at older patients over age 65, whereas this study looked at all patients over the age of 18.

“Our results suggest that the major drivers of preoperative testing are older age, procedure type, concurrent preoperative consultation, and the institution at which the procedure is conducted. Interestingly, patient co-morbidities, particularly cardiac co-morbidities, were not major drivers of pre-operative testing,” adds Bhatia.

“Preoperative testing before low-risk surgical procedures,” was published in the CMAJ.

Author block: Kyle R. Kirkham, Duminda N. Wijeysundera,  Ciara Pendrit, Ryan Ng, Jack V. Tu, Andreas Laupacis, Michael J. Schull, Wendy Levinson and R. Sacha Bhatia.

ICES is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy.

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Women’s College Hospital (www.womenscollegehospital.ca) is advancing the health of women and improving healthcare options for all by delivering innovative models of ambulatory care. Fully affiliated with the University of Toronto, the hospital is Canada’s leading academic, ambulatory hospital and a world leader in women’s health. With more than 800 physicians, nurses and health professionals, the hospital offers a range of specialized clinics and programs that are bridging the gaps in the health system. Women’s College Hospital is helping to keep people out of hospital by being at the forefront of cutting-edge research, diagnosis and treatment that will help prevent illness and enable patients to manage their health conditions. This healthcare enables Canadians to live healthier, more independent lives. At the Women’s College Research Institute, scientists combine science and patient care to develop innovative solutions to today’s greatest health challenges.

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