Effect of Nonpayment for Preventable Infections on SSI Rates Following Orthopedic Procedures

The debate regarding the effect of CMS's 2008 policy denying incremental payment for 8 complications of hospital care, also known as never events, is ongoing. Some studies have identified reductions in CLABSI and CAUTI after the policy was implemented, while others failed to find reductions in CLABSI, CAUTI or VAP, using a different dataset and methodology.  The impact of the nonpayment policy change on orthopedic procedures is less well studied.

Authors Jereen Kwong and colleagues published a study in the July ICHE that examined the effect of the policy on SSI following spine fusion, shoulder and elbow arthrodesis and repair, and spinal refusion procedures, but not hip and knee replacements (since they aren't covered under the policy). To determine the impact, they analyzed 20% of all inpatient discharges among patients ages 60 to 80yo using the HCUP National Inpatient Sample from 2000 to 2013. This is an all-payer sample in that it covers patients where Medicare is the primary payer but also non-Medicare populations.

The authors' primary hypothesis was that if the CMS policy had an impact, we would see larger reductions in SSI rates among Medicare vs control, non-Medicare patients. You can probably sense my concern immediately. How would bundles implemented to reduce SSI only have an effect on Medicare patients? It is unlikely that infection preventionists or clinicians would even have knowledge of their payor status. If non-Medicare controls have had the same exposure, they can't be used as controls!

Without getting into the methods details, the authors were expecting larger changes in SSI rates in the Medicare vs non-Medicare populations and they didn't find significant differences RR=0.9, 95% CI 0.8-1.1)  Looking at their Figure 1 below, we can see that SSI rates were slightly higher in Medicare populations (dashed line) vs non-Medicare populations before and after the non-payment policy went into effect. If I were to do this analysis, I would have looked for a change in intercept and/or slope in the SSI rates before vs after the policy combining both payor populations. Looking at the figure, there doesn't seem to be much change after the policy went into effect in either group. So we can agree with the authors that the policy had limited or no impact on SSI rates, but not for the reasons the authors state.

On the positive side, SSI rates have been declining over the entire 14-year study period - so surgeons and infection prevention folks can pat themselves on the back. Keep on doing whatever you've been doing!

Universal gloving (+/-gowning) is a horizontal intervention

Years ago, Wenzel and Edmond described horizontal vs vertical infection control interventions. Horizontal interventions were defined as those where "all infections at any site are reduced" and vertical interventions were where "only specific organisms are targeted." It always seemed to me that universal gloving and universal gowning/gloving interventions were horizontal interventions, just like hand hygiene.

Thus, why is it that when we analyze and make a case against the universal gowns and gloves intervention (or trial) we only include MRSA outcomes? Put another way, why was it designed and critiqued as a vertical intervention and not a horizontal intervention? Shouldn't we also explore potential reductions in MSSA, GNR, MDR-GNR and CDI?  Of course, a critique of this approach would be that the BUGG study didn't look at pathogens beyond MRSA and VRE (yet), so we can't.  My response is then we shouldn't do studies of horizontal interventions unless they are properly funded to collect data on all pathogens possibly reduced through the intervention. These studies should also have high construct validity including tracking of post-discharge infections. Look what happens when hand hygiene's impact is limited to just healthcare-associated S. aureus bacteremia.

If we complete underpowered and underfunded studies with poor construct validity, they might come back to haunt us. And they could harm our field - infection control. More importantly, they might even harm our patients.

Highlights from HICPAC

Good food and good conversations! Family vacation? Nope, HICPAC meeting!

The Healthcare Infection Control Practices Advisory Council just wrapped up its summer in person meeting in Atlanta and, as always, a lot to think about. Here are a few quick thoughts on my return. Dan may chime in with his own thoughts too.

1.     It is always a pleasure to spend a few days with other people who are as committed to and deeply interested in infection prevention and patient safety as the HICPAC members, liaisons from partner organizations, and CDC personnel.  DHQP director Dr Cardo was at the table with us for most of the meeting, actively engaged in the discussions.  Additionally, the Consumer’s Union Safe Patient Project had just had a meeting with CDC the day before and patient advocates stayed on to attend HICPAC and provide their own expertise to the meeting.  (One of the speakers, founder of the Lilly Foundation, noted that often a distinction is made between having ‘subject matter experts’ and ‘patient/family voices’ on committees and councils.  He pointed out that those patient/family advocates also have expertise to share.)

It is sometimes a challenge to have discussions in a public forum, with microphones, and notifying the chair of your wish to comment, waiting your turn to speak (always a challenge for me), and the formal table layout, but this meeting featured engaged and deep discussions with broad participation.  Maybe had to do with the important topics raised for discussion…

2.     Some key discussion topics at HICPAC:

a.     NHSN: How to make NHSN better. The NHSN steering group has been repurposed into a HICPAC working group, and the group is taking the opportunity to think broadly about strengths and weaknesses and priorities for improvement. (Leave your comments below – don’t we all have opinions about this?)

b.   Guidelines: How to make HICPAC guidelines more timely and more helpful, while maintaining high quality, with a specific focus on how recommendations are categorized. 

c.    Modeling: A new mathematical modeling group in the Epi Research and Innovations Branch at DHQP gave an overview of some ongoing and planned modeling work and discussed the role of modeling in addressing “knowledge gaps not amenable to traditional epidemiologic approaches”.  This section featured one of my favorite quotes of the meeting:

“Describing a complex and poorly understood reality with a complex and poorly understood model is not progress” (I missed the attribution though, so apologies for not giving appropriate credit).

3.     Lastly, a quick shout-out to Leon’s  and to the Brick Store Pub in Decatur for remarkably good food!  Try them if you are in the area. 

Dreams can come true

“Throw your dreams into space like a kite, 

and you do not know what it will bring back, 

a new life, a new friend, a new love, a new country.”

-Anais Nin

Dreams come in all shapes and sizes. Some dream of being an astronaut and others dream of an article in NYTimes Weddings with their one true love. Those of us out here in the Midwest have larger but perhaps more simple dreams. As an example, Erik Dubberke, CDI investigator extraordinaire from Wash U. in St Louis, has dreamed of making the "Times Travels" section of the Webster-Kirkwood Times. To accomplish this goal he needed to submit a photo holding the Times while traveling and he enlisted some ID colleagues to pose with him. It was great to spend a 1/2 day touring the museums of Vienna with Erik and colleagues and making a dream come true ;)

Give me back my name

“There’s a name for it,
names make all the difference in the world” 

Talking Heads

A little over two years ago, I told the sad story about how a contaminated blood culture became a central-line associated bloodstream infection (CLABSI). In that case, a “coryneform” or “diphtheroid” was more precisely identified by virtue of the adoption of mass spectrometry (MALDI-TOF) for organism identification. 

As more labs adopt technologies that provide this greater precision for species ID, it becomes more important to understand how much of an impact this might have on CLABSI rates (it’s not as if anything is riding on those rates, right?). So I was happy to see this small study in ICHE that begins to examine this issue. While this particular study is too small to help estimate the extent of the problem, it confirms that variation in species ID using different methods can impact a CLABSI designation. I hope this helps spur further evaluation not only of species ID methods, but of the broader issues around how laboratory advances impact healthcare-associated infection (HAI) definitions and rates. 

What are the next steps for evaluating the impact of species identifications on CLABSI rates? First, CDC/NHSN needs to update their master organism lists to keep up with current laboratory capacity to identify organisms, and with changing nomenclature. I know they are doing this, because I’ve been involved in that ongoing effort. Second, we should be able to use NHSN data to drill down on this problem—but can only do so if we know which lab methods are being used in each hospital for organism ID. So NHSN has now added questions to their annual survey to elicit this information. My hope is that we can use that information to compare CLABSIs among those organism groups most likely to affected by more precise species ID methods (e.g. gram positive rods).

As long as HAI definitions hinge on laboratory results, HAI rates will be very sensitive to technological advances (as well as to lab ordering practices). This dynamic receives far too little attention.

Contact Precautions for Endemic MRSA and VRE

by Andreas Voss and Eli Perencevich

This response to the recent JAMA Viewpoint by Morgan, Wenzel and Bearman is cross-posted on the “Reflections” and “Controversies” blogs. Both blogs were recently ranked "top 10" ID blogs by this recent ICHE study, so we might as well collaborate ;)

During the recent ICPIC 2017 and a pre-meeting think tank, the sense and non-sense of RCTs looking at various infection control measures was a major point of discussion during many sessions. Data from well-designed quasi-experimental studies, epidemiological evidence and logic seems to vanish whenever a new RCT is published, even if the results are not applicable to situations that are non-endemic, have higher or lower compliance with the preventive measures in question, or whether the intended measures were actually applied within the intended patient group. Some studies seem to assume that the transmission during the first days of admission are of no consequence. Others assume that given endemicity and a high patient load, the intended measures such as single-room isolation can’t be applied, even if a patient was randomized to receive those measures.

We do know that Morgan, Wenzel and Bearman are very well aware of the fine differences, but we fear that their cited research along with editorials like their viewpoint will be misinterpreted by many within the infection control community and those adjacent to infection control, such as the nurses, clinicians from other specialties, administrators, guideline makers, and legislators.

Our question would be, how many more RCTs do we need to slice and dice needed infection control measures? We believe that for as long as one can surmise an acceptable level of endemicity, deduce an allowable lack of compliance with the intended infection control measure, as well as justify the impossibility of applying the intended measures to all assigned patients, any infection control measure can be proven “unnecessary” in an RCT (or a poorly designed quasi-experimental study), and later on, in a Cochrane review. Is this what we need?

Let’s be clear about one thing. We believe that good studies in our subspecialty are needed and that evidence should be stronger than opinions. At a time when costs are critically important we need to know what to invest in. Infection control therefore needs to be effective and cost-efficient. Still we can’t help but feel that at present the “scientific pendulum” is swinging in the wrong direction.

At present, MRSA and VRE are endemic in many countries, ESBL is everywhere, and we are at a decisive moment before the same is true for CRE. Consequently, now more than ever, it is of up-most importance that we acknowledge the limitations of the existing RCTs as well as include all other available evidence in our evaluation of infection control measures. If we are forced to ignore strong epidemiological evidence supporting transmission in healthcare settings and methods for halting the spread of MDR-pathogens while waiting for the perfect study, are we really providing the safest care for our patients?