Examining the Impact on Outcomes of Structure & Process in Cancer Surgery
John D. Birkmeyer, MD
Professor of Surgery
University of Michigan Medical School
Ann Arbor, Michigan
What's the problem?
Every year thousands of Americans die or experience serious complications when they
have elective cancer surgery. The rates of complications and excess mortality vary
widely across hospitals and surgeons, with some having very low rates and others much
This variation in mortality rates suggests that the safety of cancer surgery could be
improved substantially, but quality improvement efforts are hampered because of gaps in
our current knowledge about the mechanisms that underlie variations in hospital
performance. For example, do high mortality rates at these hospitals occur because of
surgical or medical complications? Or do hospitals with high mortality rates just have
higher complication rates? Or, are these hospitals less proficient at managing
complications once they have occurred? Answers to questions like these have obvious
implications for the types of interventions that are likely to result in meaningful
quality improvement in cancer surgery.
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How does this research address the problem?
In this new grant, surgeon Dr. John Birkmeyer is using data from the 2006-2007 National
Cancer Database to study 50 hospitals. Twenty hospitals will have among the lowest cancer
surgery mortality rates in the United States (approximately 1.5%) and 30 hospitals will
have the highest mortality rates (approximately 10%). Dr. Birkmeyer and his research team
are looking at two big questions. What causes excess operative deaths at hospitals that
have high rates of cancer surgery mortality? What resources and processes of care are
responsible for differences in complications rates and mortality across hospitals?
To answer the first question, the researchers are conducting a clinical chart review to
compare cause-specific mortality rates at the low and high mortality hospitals. Evidence
that excess mortality is attributable primarily to surgical site complications would imply
the need for interventions aimed at ensuring surgeon proficiency. On the other hand,
variations in specific medical complications would suggest that the hospital needs to
focus on processes related to care during the time period after the surgery.
With a better understanding of the clinical causes of excess deaths at high mortality
hospitals, Dr. Birkmeyer and his team will then examine specific structural variables and
processes of care that underlie differences in outcomes between the low mortality
hospitals and the high mortality hospitals. They will look at factors that may reduce the
incidence of complications, such as adherence to evidence-based practices in perioperative
care. They also will examine factors that help hospitals improve rescue rates in patients
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Significance of the research & results
This innovative study promises to identify practical targets and strategies for
improving the quality of cancer surgery. Previous studies, including those assessing
correlations between surgical volume and complications or mortality rates, have
highlighted the problem of variation in hospital outcomes. However, these studies have
been based primarily on administrative data and are ill-suited for “getting under the
hood” of the variation problem. In examining detailed clinical data, this study will be
the first to identify the clinical causes of excess deaths at hospitals with high
mortality rates. It also will be unique in assessing structural factors and processes of
care that determine differences in hospital complication rates, and differences in how
successfully hospitals “rescue” patients once a complication has occurred.
Developing a better understanding of clinical mechanisms underlying variation in
outcomes will be invaluable in efforts to identify best practices and inform quality
improvement efforts at all hospitals performing cancer surgery.
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Recent related publications of interest
Hollenbeck BK, Ye Z, Dunn RL, Montie JE, Birkmeyer JD.
Provider treatment intensity and outcomes for patients with early-stage bladder cancer.
J Natl Cancer Inst 2009 Apr 15;101(8):571-80.
Birkmeyer JD, Dimick JB.
Understanding and Reducing Variation in Surgical Mortality.
Annu Rev Med 2009;60:1-11.
Improving outcomes with lung cancer surgery: selective referral or quality improvement?
Ann Surg Oncol 2009 Jan;16(1):1-2.
[View Reference Information]
Waljee JF, Windisch S, Finks JF, Wong SL, Birkmeyer JD.
Classifying cause of death after cancer surgery.
Surg Innov 2006 Dec;13(4):274-9.
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