American College of Physicians: Internal Medicine — Doctors for Adults ®

Friday, July 10, 2015

SSI prevention bundle in cardiac, hip, and knee surgery

It's really hard to write a post when you've already written the accompanying editorial. Today, I have a taller task, posting on a study led by 2 close colleagues (and favorite people), Marin Schweizer and Loreen Herwaldt. (conflict-of-interest alert) Fortunately, JAMA associate editor Preeti Malani, has done the heavy lifting with her excellent editorial.

In JAMA, Schweizer and colleagues reported the results of an AHRQ-funded trial examining the benefits of skin- and soft-tissue infection (SSI) prevention bundle in orthopedic and cardiac surgery. The bundle was outlined in a meta-analysis they published in BMJ 2 years ago and included preoperative nasal screening for methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-susceptible S. aureus, mupirocin twice a day, and daily chlorhexidine baths for 5 days if screen positive and vancomycin added to perioperative prophylaxis if MRSA positive. The quasi-experimental intervention study took place in 20 U.S. hospitals across 9 states with 39 months of pre-intervention SSI rates and 21 months of rates collected during the intervention period.

Overall, the results are impressive (i.e. not modest). First, there was a 42% reduction in SSIs after the intervention was implemented despite modest bundle adherence (39% full adherence, 44% partial adherence).

The key finding for me relates to the number of months where there were 0 SSIs across all 20 hospitals. “[T]he number of months without any complex S. aureus SSIs increased from 2 of 39 months (5.1%) to 8 of 22 months (36.4%; p=0.006 by Fisher exact test).” Seven times as many 0-months in all 20 hospitals. That's not a modest finding.

Key points from the editorial:

“inclusion of patients undergoing emergency or urgent operations, a population recognized as at high risk for SSI, improves the generalizability of the findings.”

“[T]he primary study outcome was limited to complex S. aureus SSIs, eliminating much of the subjectivity of infection surveillance. Even though surveillance practices varied among participating hospitals, complicated S. aureus SSIs are not clinically subtle and can be identified easily by any surveillance system.”

and given the modest adherence to the bundle, “Moving forward, efforts to promote and maintain adherence to prevention protocols will remain important”

“The study's setting is among its limitations. All 20 study sites were from a single health care system with a well-established quality improvement infrastructure—certain factors in this health care system may differ from other clinical settings, including a below-average baseline infection rate. It remains unclear what challenges and barriers may present as this bundle is implemented at other institutions. Further studies in different settings will offer additional guidance.”

and my favorite quote: “Although getting to 0 is unlikely to be achievable, efforts that move closer to this elusive goal hold tremendous value for clinicians, hospitals, payers, and, most importantly, patients.”

My final thoughts:

This is a wonderful study that took many years of planning, hard work and tremendous collaborators, including HCA and Ed Septimus. Congrats to all involved. Not every study is a grand slam, but we'll take a home run for infection prevention.

Eli N. Perencevich, MD, ACP Member, is an infectious disease physician and epidemiologist in Iowa City, Iowa, who studies methods to halt the spread of resistant bacteria in our hospitals (including novel ways to get everyone to wash their hands). This post originally appeared at the blog Controversies in Hospital Infection Prevention.

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Anonymous Anonymous said...

I am a former hospital epidemiologist and baseball player. With all due respect this study is an infield single, not a home run. The design was an uncontrolled interrupted time series. This is a non-experimental design with no concurrent control group. It is prone to serious biases that are too numerous to count. By the authors own admission the primary outcome was only modest in effect. Someone please calculate the number needed to treat and do a cost analysis for this bundle. Even then, we must be concerned that bias and/or unmeasured confounding led to a spuriously high effect away from the null. The food and drug administration would never let a new drug be approved using such a weak study design. Why do we in hospital epidemiology continue to perform uncontrolled before-after studies and uncontrolled time-series studies. We are all trained well enough in research methodology to know better. This study is at best hypothesis generating only. The next step should be at least two (the FDA standard for approval of a new drug) well designed randomized controlled trials. One could be randomized by individual patient (please blind investigators and study subjects to the intervention), and the other could be a cluster randomized trial by hospital, although cluster RCTs are prone to contamination bias in the control group and cannot be double blinded. It is time for the field of hospital epidemiology to grow up.

July 11, 2015 at 3:50 PM  
Anonymous Anonymous said...

Interesting comments by anonymous above. I would disagree on most of your points. First this is an experimental (quasi-experimental) design with time-series analysis. This is near the highest level of evidence just below a randomized trial. Second, the same authors have published a meta-analysis of all prior trials showing a similar effect - See: Of course, we can disagree on effect size, but cutting surgical infections in half among orthopedic (hip/knee) patients is more than modest in my book. Since the cost of the intervention is very cheap (a few dollars of mupirocin and CHG), it is very likely to be cost effective, but sure, someone can do a cost-effectiveness analysis if they wish.

And anyone who tells hospital epidemiology to "grow up" has to carefully assess the funding of prevention trials vs intervention trials. No one funds prevention trials studies. I am sure if you are willing to help find $10 million for an individual randomized trial and another $6 million for a cluster trial to test an intervention that has (a) biological plausibility and (b) proven by meta-analysis and now this well designed time-series analysis, we would be happy to spend the money on new trials - although, this bundle is proven, so we might spend it testing some unproven intervention.

October 2, 2015 at 4:35 PM  

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Members of the American College of Physicians contribute posts from their own sites to ACP Internistand ACP Hospitalist. Contributors include:

Albert Fuchs, MD
Albert Fuchs, MD, FACP, graduated from the University of California, Los Angeles School of Medicine, where he also did his internal medicine training. Certified by the American Board of Internal Medicine, Dr. Fuchs spent three years as a full-time faculty member at UCLA School of Medicine before opening his private practice in Beverly Hills in 2000.

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Ira S. Nash, MD, FACP, is the senior vice president and executive director of the North Shore-LIJ Medical Group, and a professor of Cardiology and Population Health at Hofstra North Shore-LIJ School of Medicine. He is Board Certified in Internal Medicine and Cardiovascular Diseases and was in the private practice of cardiology before joining the full-time faculty of Massachusetts General Hospital.

Zackary Berger
Zackary Berger, MD, ACP Member, is a primary care doctor and general internist in the Division of General Internal Medicine at Johns Hopkins. His research interests include doctor-patient communication, bioethics, and systematic reviews.

Controversies in Hospital Infection Prevention
Run by three ACP Fellows, this blog ponders vexing issues in infection prevention and control, inside and outside the hospital. Daniel J Diekema, MD, FACP, practices infectious diseases, clinical microbiology, and hospital epidemiology in Iowa City, Iowa, splitting time between seeing patients with infectious diseases, diagnosing infections in the microbiology laboratory, and trying to prevent infections in the hospital. Michael B. Edmond, MD, FACP, is a hospital epidemiologist in Iowa City, IA, with a focus on understanding why infections occur in the hospital and ways to prevent these infections, and sees patients in the inpatient and outpatient settings. Eli N. Perencevich, MD, ACP Member, is an infectious disease physician and epidemiologist in Iowa City, Iowa, who studies methods to halt the spread of resistant bacteria in our hospitals (including novel ways to get everyone to wash their hands).

db's Medical Rants
Robert M. Centor, MD, FACP, contributes short essays contemplating medicine and the health care system.

Suneel Dhand, MD, ACP Member
Suneel Dhand, MD, ACP Member, is a practicing physician in Massachusetts. He has published numerous articles in clinical medicine, covering a wide range of specialty areas including; pulmonology, cardiology, endocrinology, hematology, and infectious disease. He has also authored chapters in the prestigious "5-Minute Clinical Consult" medical textbook. His other clinical interests include quality improvement, hospital safety, hospital utilization, and the use of technology in health care.

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Matthew Mintz, MD, FACP, has practiced internal medicine for more than a decade and is an Associate Professor of Medicine at an academic medical center on the East Coast. His time is split between teaching medical students and residents, and caring for patients.

Everything Health
Toni Brayer, MD, FACP, blogs about the rapid changes in science, medicine, health and healing in the 21st century.

Vineet Arora, MD, FACP, is Associate Program Director for the Internal Medicine Residency and Assistant Dean of Scholarship & Discovery at the Pritzker School of Medicine for the University of Chicago. Her education and research focus is on resident duty hours, patient handoffs, medical professionalism, and quality of hospital care. She is also an academic hospitalist.

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John H. Schumann, MD, FACP, provides transparency on the workings of medical practice and the complexities of hospital care, illuminates the emotional and cognitive aspects of caregiving and decision-making from the perspective of an active primary care physician, and offers behind-the-scenes portraits of hospital sanctums and the people who inhabit them.

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Ryan Madanick, MD, ACP Member, is a gastroenterologist at the University of North Carolina School of Medicine, and the Program Director for the GI & Hepatology Fellowship Program. He specializes in diseases of the esophagus, with a strong interest in the diagnosis and treatment of patients who have difficult-to-manage esophageal problems such as refractory GERD, heartburn, and chest pain.

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Mike Aref, MD, PhD, FACP, is an academic hospitalist with an interest in basic and clinical science and education, with interests in noninvasive monitoring and diagnostic testing using novel bedside imaging modalities, diagnostic reasoning, medical informatics, new medical education modalities, pre-code/code management, palliative care, patient-physician communication, quality improvement, and quantitative biomedical imaging.

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William Hersh, MD, FACP, Professor and Chair, Department of Medical Informatics & Clinical Epidemiology, Oregon Health & Science University, posts his thoughts on various topics related to biomedical and health informatics.

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David L. Katz, MD, MPH, FACP, is an internationally renowned authority on nutrition, weight management, and the prevention of chronic disease, and an internationally recognized leader in integrative medicine and patient-centered care.

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Richard Just, MD, ACP Member, has 36 years in clinical practice of hematology and medical oncology. His blog is a joint publication with Gregg Masters, MPH.

Kevin Pho, MD, ACP Member, offers one of the Web's definitive sites for influential health commentary.

MD Whistleblower
Michael Kirsch, MD, FACP, addresses the joys and challenges of medical practice, including controversies in the doctor-patient relationship, medical ethics and measuring medical quality. When he's not writing, he's performing colonoscopies.

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Elaine Schattner, MD, FACP, shares her ideas on education, ethics in medicine, health care news and culture. Her views on medicine are informed by her past experiences in caring for patients, as a researcher in cancer immunology, and as a patient who's had breast cancer.

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More Musings
Rob Lamberts, MD, ACP Member, a med-peds and general practice internist, returns with "volume 2" of his personal musings about medicine, life, armadillos and Sasquatch at More Musings (of a Distractible Kind).

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Reflections of a Grady Doctor
Kimberly Manning, MD, FACP, reflects on the personal side of being a doctor in a community hospital in Atlanta.

The Blog of Paul Sufka
Paul Sufka, MD, ACP Member, is a board certified rheumatologist in St. Paul, Minn. He was a chief resident in internal medicine with the University of Minnesota and then completed his fellowship training in rheumatology in June 2011 at the University of Minnesota Department of Rheumatology. His interests include the use of technology in medicine.

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Neil Mehta, MBBS, MS, FACP, is interested in use of technology in education, social media and networking, practice management and evidence-based medicine tools, personal information and knowledge management.

Peter A. Lipson, MD
Peter A. Lipson, MD, ACP Member, is a practicing internist and teaching physician in Southeast Michigan. The blog, which has been around in various forms since 2007, offers musings on the intersection of science, medicine, and culture.

Why is American Health Care So Expensive?
Janice Boughton, MD, FACP, practiced internal medicine for 20 years before adopting a career in hospital and primary care medicine as a locum tenens physician. She lives in Idaho when not traveling.

World's Best Site
Daniel Ginsberg, MD, FACP, is an internal medicine physician who has avidly applied computers to medicine since 1986, when he first wrote medically oriented computer programs. He is in practice in Tacoma, Washington.

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American Journal of Medicine
Also known as the Green Journal, the American Journal of Medicine publishes original clinical articles of interest to physicians in internal medicine and its subspecialities, both in academia and community-based practice.

Clinical Correlations
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One of the most popular anonymous blogs written by an emergency room physician.

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