The “horizontalists”

Contact precautions, blah, blah, blah. Regular readers know that this is one of the topics we revisit often. Yet in my decade as a hospital epidemiologist, I never suggested we stray from the current CDC guidance on use of CP in healthcare settings. Why? For one thing, I was a VA hospital epidemiologist--but VA or not, it is a real challenge to convince colleagues and hospital administrators to make such a major practice change, especially if it is not consistent with existing authoritative guidance. No one wants to be an outlier on an issue like this, perhaps fearing not only increased infection rates but also repercussions from JCAHO or other surveyors. Or maybe I just don’t have the courage of my convictions (one of those convictions being that “horizontal” population-based approaches are more effective overall, and in the long run, than are pathogen-based “vertical” approaches). Not everyone has been so hesitant to put this theory to the test, however. Below are excerpts from a current thread on our Emerging Infections Network listserve:

We are looking into getting rid of isolation gowns, exclusively for MRSA and VRE in a relatively small teaching hospital. We are planning on focusing more on handwashing and glove use when appropriate, as well as monitoring for any changes in the rate of HAI. I have heard through the grapevine that there are other institutions that gave up on MRSA and VRE contact isolation. At this point we are not using active surveillance with swabs, but we do isolate MRSA and VRE based on finding them in any clinical cultures or based on historical data from previous admissions, which does not make much sense to me. I am interested to hear opinions from the forum, especially from people who went through a similar process. What are the barriers that you encountered? What are people thinking of the 2 papers that came out in April in NEJM? (neither of which apply to what we are doing now, since we are not swabbing noses regularly, but still....we are going completely opposite way of what the VA did).

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Date: Mon 15 Aug 2011 11:37 We do not isolate MRSA or VRE. Our area has an exceptionally high incidence on CA-MRSA, and the Dept of Public Health has endorsed this approach as well. I think, when you examine any "bundled" approach, hand hygiene is the key factor, tho often it is difficult to break out. I am as concerned about transmission from the patients we don't know are colonized as much as those we know about, so support a "universal" approach.

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Date: Mon 15 Aug 2011 12:53 Hi - At [ ] Medical Center we are 9 months into our change to the policy you describe emphasizing vigorous adherence to standard precautions and eliminating contact precautions for VRE and MRSA. We are currently analyzing the data but do not have any change in infection rates to report. We will also be looking at bed flow and additional quality of care factors in respect to the change.



My own opinion on the discrepancies seen in the literature in regards to the topic are that where hand hygiene improvements were possible interventions such as the VA study make an impact but places such as the Swiss study released a few years ago where hand hygiene was in place there is no or minimal added benefit from applying the contact precautions.

I like our current approach where the emphasis is on preventing transmission in all patients regardless of their known colonization/ infection status as opposed to raising the alarm and isolating a subset of the population who may or may not be the true culprits in terms of current/active shedding of resistant organisms.

Contact precautions, and why I hate them, entry number next

Regular readers of this blog know that we’ve raised many questions about contact precautions (CP). We have very few arrows in our quiver to fight multiple-drug resistant organisms (MDROs). CP is one of them. So naturally it has become infection prevention dogma that CP is necessary to control MDRO spread. Never mind that the effectiveness of CP has really only been demonstrated in outbreak settings, that adherence to CP is often terrible, and that CP likely has several nasty unintended consequences that can harm patients. The bottom line? We desperately need more research, both to address the effectiveness of CP at preventing pathogen transmission, and to address the potential unintended consequences of widespread application of CP.

Regarding the latter (unintended consequences), we have two recent additions to the literature courtesy of Eli and his homeys back in Maryland. The first study, led by Dan Morgan, examines the relationship between CP and adherence to several quality-of-care process measures (e.g. SCIP, pneumonia, CHF, acute MI), and the second study, led by Hannah Day, examines the relationship between CP and depression among acute care inpatients.

I have an obvious conflict of interest and will therefore not critique either study. Instead I will leave it to you, dear reader, to assess their quality and to leave any comments, positive or negative, that you wish.

Nothing a little duct tape can't fix....

A couple years ago Mike blogged about a simple way to make contact precautions more friendly, involving floor colors that divide the immediate “patient zone” (where gowns and gloves are needed) from a zone in which healthcare workers can communicate with the patient without those barriers. Of course, it costs a bit of money to paint floors or change flooring, so some industrious IPs at Trinity Regional Health System (here in the great Midwest!) decided to take the same approach using red duct tape. They presented their findings at the APIC meeting last week. I’m sure there will be some unintended consequences here (does the duct tape interfere with room disinfection? Will it roll up or buckle and pose a trip-and-fall risk?). Still, I like their willingness to attack this problem with a simple and low-cost solution.

Pre-emptive contact precautions of intubated patients: effective??

One of the odd things about contact precautions is that they are typically used to isolate patients colonized or infected with MDROs like MRSA. What this does is protect the healthcare worker from being contaminated with the MDRO but does little to protect the uncolonized patients.  The contact "event" we should MOST care about is contact between the contaminated or colonized healthcare worker and the uncolonized patient. So, current active detection and isolation programs have it all wrong. Please read that paragraph again.

Thus, I read with interest a paper just e-published in the JHI by Matsushima et al.  The authors noticed, using surveillance data, that ventilated patients in their ICU were 8 times as likely to acquire MRSA compared to non-ventilated patients.  Based on this finding they decided to place all ventilated patients on contact precautions throughout their stay to see if it reduced MRSA acquisition.  This intervention is close to a universal contact precautions intervention (or close to the STAR*ICU study that was a study of barrier precautions - gloves or gowns/gloves).

The study was completed in a 19-bed ICU in Osaka, Japan.  A unique (for the US at least) characteristic of this ICU was that only 2 rooms were single-bed rooms while the remaining 17 beds were in a single open ward. There were 2 study periods.  Period 1 occurred during 2004 and period 2 was a 3-year period from 2005-2007. During period 1, contact precautions were only used if the patients was found to be colonized with an MDRO. Surveillance cultures were obtained on all admissions and weekly using sputum, nasal and urine sources. During period 2, the same practices existed as period 1, but all patients who were intubated were placed on contact precautions for their entire stay.  MRSA acquisition occurred when a patient negative for MRSA on admission culture became positive on a subsequent surveillance or clinical culture.  They actually completed segmented Poisson regression looking for changes in slope/intercept of HA-MRSA rates. Woo woo!

The main difference between period 1 and period 2 was that many more people were placed on contact precautions during period 2. In period 1, 2.9% of patients were MRSA+ on admission and isolated while in period 2, 6.1% of patients were MRSA+ on admission, but fully 43% of patients were placed on contact precautions. Importantly, the colonization pressure was 2x greater in period 2.  Keep that in mind...

Interestingly, HA-MRSA infection in all patients declined from 3.6 to 2.3 per 1000 patient-days, p<0.05. The incidence of HA-MRSA in the intubated patients greatly decreased from 12.2% to 1.1%. I have pasted the key figure -->.  What it shows is that while HA-MRSA colonization and infection declined in intubated patients it actually slightly increased in non-intubated patients (who could be considered a non-equivalent control group).  Very cool.

Usual caveats: single center with somewhat unique bed arrangement in the ICU, and of course the control group wasn't random.  However, this is a fairly strong quasi-experimental study with good epi and statistical methods. And it points out that isolating patients actually PROTECTS them, so if there are downsides associated with contact precautions, like fewer visits from healthcare workers, at least the patients isolated directly benefit from the isolation.  This sort of study could actually help flip how we think about contact precautions. Isolate the uncolonized!

Matsushima et al. JHI 2011, doi:101016/j.jhin.2011.02.010

h/t Marin Schweizer

STAR*ICU study published: Barrier precautions not effective

It's only one study. Everybody take a deep breath. OK, exhale.

You might have already heard about this study and you might even know the results.  Someday, someone might discuss how this study was designed, and why the investigators decided to ship all of the microbiology specimens to NIH for processing resulting in a 5-day test turn-around time.  Someday, someone might explain why this study took 4 years to publish and the saga behind its eventual publication in the NEJM.  Someday, someone might even discuss how the difficulties completing this study might be hindering NIAID from funding other infection prevention clinical studies.  Someday, someone.

What can I say about the study?  Barrier precautions (ie. gloves or gowns/gloves) are ineffective in halting the transmission of MRSA and VRE in ICU settings.

Methods: The cluster-randomized trial (ie a largish quasi-experimental study but with a cool fancy name - see my "Random note" below) was completed in 2006 with the intervention lasting 6 months from March to August 2006. There were 10 intervention ICUs and 8 control ICUs.

Random note: There were 18 ICUs in this study, so it's somewhat like an 18-person RCT.  With such small numbers you can't expect that all measured and unmeasured confounders to be randomly distributed between the intervention and control ICUs. Thus, this is more like a large QE study than a standard RCT and needs to be analyzed as a QE study using multivariable regression controlling for known sources of confounding. Don't believe me? Check out Table 2 to see how different the intervention and control arms were in regards to topical and systemic antimicrobial exposure. You would not typically expect these "significant" differences in a large RCT (or large cluster-RCT).

Microbiology: Nasal swabs for MRSA surveillance cultures and stool or perianal swabs for VRE surveillance cultures were obtained from all patients within 2 days after their admission to the ICU, weekly thereafter, and within 2 days before or after their discharge from the ICU. Swabs were shipped overnight, 6 days a week, to the NIH. The mean number of days from obtaining surveillance cultures to reporting of results was 5.2 days.  I would have liked to see this reported in median days and I would also have liked this number to be reported from time of admission and not time from obtaining the culture since 2 days could pass between admission and obtaining the culture.

Planned Intervention: Known colonized or infected patients were placed on contact precautions. All other patients were placed on universal gloving from the time of admission until their discharge or until the results of surveillance cultures results returned. If surveillance cultures were positive, patients were upgraded to contact precautions (gowns/gloves) and if they were negative, they were downgraded to standard precautions.

Actual intervention as implemented: In the intervention ICUs, 92% of the ICU-days were spent under barrier precautions (51% contact precautions and 43% universal gloving) while in the control ICUs, 38% of ICU-days were spent under contact precautions.  Thus, indepedent of what anyone says, this study is about whether increasing barrier precautions from 38% to 92% reduces transmission. Also, 4 times as many patients in the intervention group were exposed to a topical antimicrobial (e.g. mupirocin), 12% vs 3.2%. Now, some will say that there wasn't 100% compliance with these interventions. I agree, this is not an efficacy trial.  As Ebb and I said in our JAMA commentary yesterday, cluster-randomized trials are real-world effectiveness trials in the domain of infection prevention.

Compliance: Overall, 47% of contacts in the intervention arm occurred with clean gloves and exit hand hygiene compliance vs 25% in the control ICUs. Compliance with contact precautions was relatively good in the intervention ICUs: gloves 82% and gowns 77%. Hand-hygiene compliance was also higher in the intervention vs. control ICUs (69% vs 59%)

MRSA or VRE colonization or infection: The mean incidence of MRSA or VRE per 1000 patient days at risk was actually higher in the intervention arm than the control arm (40.4 vs 35.6, p=0.35) but this was not statistically significant.

My thoughts:  How can this study not find a benefit when so many others have? Since most of the previous studies were uncontrolled quasi-experimental studies and we know that uncontrolled QE studies can over-estimate the measure of effect, it is possible that barrier precautions don't work.  It is also possible that other factors need to be included in any MDRO prevention program including attention to environmental cleaning and far higher compliance with the hand hygiene and contact precautions. However, the compliance rates reported in this study are not abnormally low (at least at the mean/median). Finally, perhaps decolonization is needed to achieve the results (at least for MRSA) that we've seen in other studies.

Another criticism that we've heard and will hear again is that the turn-around time for the microbiology was too-long.  This is mostly a red herring.  Since we have little evidence that gowns add much to gloves, and 92% of contacts in the intervention arm occurred with gloves, this study had FAR better glove compliance than we would expect with any typical ADI program in the real world.  The use of universal gloves in the pre-result period in the intervention arm really saved this study and, thus, it provides VERY useful information and should not be discounted. A quicker test turn-around would not have magically led to reduced transmission. Sorry.

Again, this is one study and it shouldn't be the last.  AHRQ is funding some very important MRSA (and VRE) prevention trials that many of us are involved with and I hope the publication of this paper won't discourage AHRQ (or NIH or CDC or VA) from funding these large and important studies.

What this study really tells us is that we can't fall back on legislative mandates in MDRO prevention and we must continue to search for the right combination of interventions along with developing better implementation strategies. Don't stop with the STAR*ICU study. Let this be the beginning.


Huskins W.C. et al. NEJM April 14, 2011

Do Contact Precautions Cause Depression?

STOP Contact Precautions?

Mike has written several time about his concerns for the side-effects of contact precautions. (see his kill contact precautions, personal view and adverse effects posts). His post "adverse effects" discusses Dan Morgan's systematic review that looked at the state of the literature measuring what has become dogma for many hospital epidemiologists and clinicians: contact precautions harm people. After completing this review, we weren't entirely comfortable with the literature, so we set out to complete our own series of studies seeking to assess the association between contact precautions and adverse outcomes. 

The first such study by Hannah Day, a PhD student working with Dan Morgan and me, has just been published in the March 2011 AJIC.  It was a pilot study that allowed us to gather baseline estimates to complete power calculations for the larger studies that will follow. She measured the baseline levels of depression and anxiety in patients admitted to non-ICU wards of an acute-care VA hospital. Of note: this study was a sub-study within an MRSA prediction-rule study that we'd published earlier and Dan Morgan posted on a few months ago. (see Veteran's Day MRSA post)

In 2009, 103 patients (20 on contact precautions and 83 unisolated) were approached within 48 hours of admission and received a questionnaire that included a body of questions called the HADS - Hospital Anxiety and Depression Scale. What did she find?  The HADS score was 2.2 points higher in patients on contact precautions (p=0.21).  The odds ratio for having either depression or anxiety was nearly twice as high on contact precautions (OR=1.87, 95% CI 0.61-5.69).  Yes, the study was under powered.  Intriguingly, the increased HADS scores associated with contact precautions exposure was higher in those patients newly isolated (<1 year since first isolated).

Before everyone gets too excited, what does a HADS score difference of 2.2 mean? Well, this study was too small to determine whether this increase was due to depression or anxiety.  Additionally, with the combined scale, a minimum difference of 3.0 is considered clinically significant.  Thus, even if there is an association, it may have little clinical meaning.  Finally, the HADS was measured on admission, so we were unable to determine if isolation "caused" the depression. To do that, we would need to do repeated measurements on admission and throughout the stay to see if there was a change in HADS later in the admission.  More exciting data to come...

Day HR et al. Am J Infect Control March 2011

I'm still in scrubs...

There's a new paper in the Journal of Hospital Medicine that takes a look at one of my favorite topics, the role of the white coat in the transmission of nosocomial infections and the impact of bare below the elbows.

Investigators at Denver Health performed a randomized, controlled trial to assess the degree of bacterial colonization and contamination by MRSA on work clothes. The participants were 100 physicians (residents and attendings) on the internal medicine service who were randomized to wear either their personal white coat (subjects were not given prior notification to avoid laundering for the purpose of the study) or a freshly laundered short-sleeved uniform. After eight hours at work, the coats and uniforms were cultured at designated sites using RODAC plates.

The main findings of the study were:

• No difference in overall bacterial counts between the white coats and the uniforms
• No difference in MRSA contamination (16% for white coats vs. 20% for uniforms, p=0.6)

There are a number of potentially confounding issues for which we don't have information:

• What is the prevalence of MRSA infection and colonization among internal medicine service patients at this hospital?
• Does the hospital have a MRSA active detection and isolation program for MRSA?
• Are patients with MRSA placed in contact precautions? If so, what is the compliance with contact precautions?
• Are the white coats hospital issued (thereby implying a uniform fabric) or purchased by physicians (implying various types of fabric) and of what type of fabric were the uniforms constructed? Previous studies have shown that duration of contamination by important pathogens can vary with the type of fabric.

Also, were there any differences after randomization between those who wore the white coats vs. those who wore the uniforms? More importantly, I think the biggest concern with the study is that it's relatively small, from a single service in a single hospital, making external validity questionable. And MRSA is only one of several important pathogens that need consideration.   

One of the most important issues in hospital infection prevention today is the role of clothing in the transmission of nosocomial pathogens. This not only impacts the issue of whether healthcare workers should wear neckties and white coats, but also has an impact on whether contact precautions should continue. It's important to note that the entire rationale for plastic gowns in contact precautions is the assumption that contaminated clothing can transmit pathogens to patients. If that's not true we sure could save the planet from a huge amount of disposable plastic and healthcare workers a lot of grief. We desperately need a funded, large, multicenter, well designed trial to answer the questions once and for all as to whether we go bare below the elbows or kill contact precautions.

While I think the authors of this study should be commended for addressing an important topic, I don't think many people will be swayed by its results. Those believers in the white coat will find the results reassuring and the pro-bare-below-the-elbows crowd will focus on the external validity of the study. 

Sunday Times blogging

This report from Arizona serves as a disturbing reminder of how quickly bad health outcomes data can be turned into bad public policy. And this report from Zimbabwe provides some needed perspective on the enormous healthcare gap between the richest and poorest nations. If we had to steam-clean all disposable gloves for re-use, we'd probably find some alternatives to widespread use of contact precautions!

Expand contact precautions? NO!!!!!!!

The Associated Press has an article today on infection prevention efforts at the University of Maryland Medical Center (Eli's old stomping ground). One of the interventions noted is universal contact precautions in the surgical intensive care unit. My thinking on control of multidrug-resistant pathogens is actually moving in the opposite direction. I think that high rates of hand hygiene compliance (particularly if coupled with standard precautions and a bare-below-the-elbows approach) will be shown to be as effective as contact precautions. Another useful approach may be universal gloving (we have found that to be as effective as contact precautions in the ICU setting). And I really don't think it's reasonable for family members to be required to wear gowns if they are not visiting other patients. However, the article's description of the white coat as a "walking germ" was great!

Are we ready to kill contact precautions?

Pauline Chen, in her New York Times column, Doctor and Patient, takes on contact precautions this week. Her piece, When Isolation Hampers More than Bacteria, is one of the first in the mainstream media to point out the unintended consequences of contact precautions. This has been a recurring theme on our blog. In one of the very first postings on this blog, Dan wrote a piece entitled, Why I hate contact precautions. Just this week I was asked by a concerned medical student to review the case of an elderly man hospitalized for over 3 months and confined to a lonely hospital room because a nasal swab grew MRSA. "Can't we just allow him to sit in the hallway?" asked the student. And we figured out a way to do that. Dan Morgan states in Chen's piece: “There is a misperception that infections are the single worst adverse event that can happen in a hospital.”  Also quoted in the piece is my colleague, Gonzalo Bearman, regarding our studies comparing universal gloving and contact precautions, which found no difference in infection rates when the two strategies were compared. Maybe it's finally time to think about moving beyond contact precautions.

Contact precautions: A very personal view

The latest issue of the Annals of Family Medicine has an interesting essay, "Losing Touch in the Era of Superbugs," by a physician who struggles with contact precautions. Recently hospitalized with a MRSA infection, he has a new fear of becoming infected at work, yet realizes how important human touch is in the practice of medicine. It's a great reminder of how contact precautions interferes with providing the most humane care to our patients. You can read the full text of the essay here.

Today's Science Times

Every Tuesday brings the Science Times section of the New York Times. This morning, there are two articles of interest for our readers:

• There's an article on bedbugs which explains the reasons why they have become so common in recent years.
• There's an essay on isolation by Abigail Zuger, an infectious diseases physician, which focuses on the human dimensions of a practice that can be rather cruel to patients. She writes of an elderly woman placed in isolation for C. difficile who sobbed continuously: "Increasingly, modern medicine forces us to specialize in the invisible. Here we had invisible germs with an inviolable mandate, and an all too visible patient pleading with us to ignore it. It was quite a struggle to try to see the one, to try not to see the other."

Adverse effects of contact precautions

There's a new systematic review on the adverse effects of contact precautions in the Journal of Hospital Infection. This paper's methods and findings are very similar to Dan Morgan's paper (with Dan Diekema, Kent Sepkowitz and Eli Perencevich as co-authors) from last year. There are a few papers that are not found in both reviews, but no newer papers are covered in the new review. The conclusions of the two papers are largely the same:  contact precautions are overall associated with adverse unintended consequences for patients in the observational studies that have been published.

Gloves and gowns are not enough...

Back at Maryland, we had a surgeon who always asked for evidence that hand hygiene was necessary if he wears gloves. We gave him some evidence, but like many clinicians, he wanted data from his own institution. I guess everyone is the exception. Like good soldiers, we proceeded to collect that data. We gathered a great team over the years - Graham Snyder, Stephen Liang, Catherine Smith, Hannah Day and others to approach healthcare workers (HCW) before they entered patient rooms and collect cultures on their hands before entry and gowns/gloves after exiting the room.

The initial study from this work was published by Graham Snyder et al in ICHE 2008. He reported that MRSA was detectable on 19% of gowns/gloves of HCW after exiting an MRSA+ patients room, while that result for VRE was 9%.

The latest report from this group published in this month's ICHE by Dan Morgan et al, provides somewhat more humbling data. HCW had MDR-acinetobacter on their gloves 36% of the time after entering a colonized/infected patient's room. Wow. But the truly humbling finding was that after removing their gloves, 4.5% of the HCW still had it on their hands. Thus, while gloves reduce contamination of hands by around 85% per contact, to achieve true infection prevention, HCW must wash their hands after they remove there gloves.

I have posted Table 2 from the paper, which shows the likelihood of HCW contamination that would occur at various levels of compliance with contact precautions and hand hygiene. Even with 90% compliance with both wearing gloves and hand hygiene, almost 1% (0.8%) of contacts would be expected to contaminate the HCW hand and place them at risk for contaminating other patients and the environment. Multiply that 1% (or higher if lower compliance exists) by the number of HCW that enter the patients room in a day and you have an estimate of the daily transmission of MDR-AB. This sort of data highlights the Achilles heal of active detection and isolation strategies. No matter how much effort and money go into rapid detection of MDR organisms, without 100% compliance to gowns and hand hygiene, the effort is wasted. We have shared this data with our favorite surgeon. The description of how that went must wait for another study, or at least another day.

Graham Snyder 2008 ICHE paper (here)
Dan Morgan July 2010 ICHE paper (here)

Benefits of Universal Gloving

Last but not least in the May issue of ICHE, Gonzalo Bearman and our very own Mike Edmond from VCU in Richmond, completed a nice quasi-experimental study looking at the benefits of universal gloving for all patient contact vs. standard contact precautions in their 18-bed surgical ICU. In phase 1 from September '07 to March '08, only standard contact precautions based on passive (clinical culture-directed) surveillance were used while in phase 2 from March '08 to Sept '08 universal gloving with emollient-impregnated gloves was used without contact precautions. During both phases, admission and every 4 day surveillance cultures were performed for MRSA and VRE but for study purposes only and not shared with the clinical teams.

So what happened? Only good things. Universal gloving compliance was 78% in phase 2 and was associated with higher hand hygiene compliance on entry (5% higher) and exit (12% higher). It also appears that universal gloving was associated with reduced CLABSI and catheter-UTIs, but with p-values = 0.1 for both outcomes. C. difficile was also lower (2.0/1,000 patient-days down to 1.4/1,000) but this finding was not statistically significant, p=0.53. VAP rates were the same (1.0 vs 1.1/1000 device days) The most important finding, in my opinion, was that HCW were less likely to have MRSA and VRE contaminating their hands during the universal glove phase. Despite what the authors state (Mike don't be mad!), the study was not likely powered sufficiently to find reduced acquisition, given that MRSA acquisition was reduced by 50% with universal glove (2.9/1000 patient-days vs. 1.4/1000 patient days) but this had a p=0.2.

I think overall, that these findings suggest that universal gloving shows promise warranting further study. I wonder if they stopped universal gloving after the study period? If they did, this would make for a very epidemiologically sound quasi-study (roll-in and roll-out) which could be analyzed using more powerful segmented Poisson regression,which can detect a change in slope and intercept associated with starting or stopping the intervention.

The June ICHE just appeared online 5 minutes ago...more exciting evidence for us to review!

Compliance with contact precautions: Not so much

Elaine Larson's group has a new study in the American Journal of Infection Control that examines compliance with contact precautions at 3 hospitals in New York City. She found that 15% of patients who had indications for contact precautions were actually not isolated. For patients who were isolated, hand hygiene by healthcare workers on room entry was very low at 22% and on room exit at 59%. Compliance with gowns was 71% and with gloves 72%.

With the compliance levels demonstrated here it seems unlikely that these hospitals could be successfully preventing infections. I am increasingly convinced that effective infection prevention hinges on high levels of compliance with very basic practices. It's not rocket science.