Outcome bias

I grew up in Wheaton, Illinois, one of Chicago’s western suburbs, and became a Cubs fan by default. All my friends were Cubs fans, my dad took us to Wrigley for games (never Comiskey!), and the Cubs games were televised on channel 9 while the White Sox were usually on a UHF channel (44) that was hard to tune in (if you remember wiggling a dial to get your grainy local UHF signals, you are old like me). The photo above is from a game I attended in 1969 with my family. That year, and every year since 1945, ended the same way: with the Cubs failing to win the NL pennant. 

So last night’s victory is a gigantic step forward for the Cubs, who will now play Cleveland in the World Series. By now you’re asking, “yes, but that’s a game and this blog is about infection prevention, what’s the connection”?

See Cub manager Joe Maddon’s quote in this piece, about how he approaches challenges:

“When you get to this particular moment, to try to avoid being outcome-biased, just . . . continue to work on the process, which is inning by inning — score first, win the inning. Those are the kind of thoughts that get you beyond this moment.”

I think you can interpret this quote in two ways, each of which applies to infection prevention. 

First, he may have meant to say “avoid being outcome-focused”. In other words, stop wasting energy worrying about your outcomes, instead put your energy into the processes that you know will, eventually, move the outcome in a favorable direction. This is becoming increasingly difficult in infection prevention as CMS PFP programs put more and more pressure on rates. The temptation is to put time and energy into activities that might impact the outcome quickly but without doing anything to improve the safety of patients (gaming the definitions, empiric treatment approaches, changing lab practice). Counterproductive, and in many cases also bad for patients.

Alternatively, he could have been literally referring to “outcome bias”, which is an error in evaluating the quality of a decision, or the effectiveness of a practice, when the outcome is already known. This might lead one to deviate from an effective practice because a bad outcome occurred in the past when the practice was in place, or to institute a dubious practice because prior implementation was coincident with a favorable outcome. This ignores the fact that outcomes are often influenced by a myriad of factors, many of which are not understood or not under the decision-maker’s control.

The infection prevention take-home from either interpretation? Focus on those practices that have been demonstrated to improve outcomes--keep your eye on the process and the outcomes will follow. Avoid gimmicks that might move the outcome needle but for which no evidence exists that patients will benefit.

P.S. I hope to see you at IDWeek in New Orleans!  I'll be joining Debbie Goff on Saturday morning to talk about social media, and Thursday will be facing off with Cliff McDonald about the C. difficile screening issue!  We will also be presenting four-center data on the ongoing M. chimaera outbreak on Saturday afternoon. If I am mysteriously absent from any of the above, it's because I'm on a plane headed to Cleveland or Chicago, to try to sneak in to a World Series game!

Time, Power and Infection Prevention

With the increased attention to infection prevention and antimicrobial resistance globally, we now have more seats at the table. In fact, many of us are or will soon be at the table in positions of leadership (power) in our hospitals or organizations. We can include our colleagues at CDC, who are being asked to do more and manage larger research portfolios. The time we imagined 10-20 years ago, where our clinical and research roles would be appreciated is now, but with the now comes an overwhelming urgency - we are overworked.

With that in mind, I read a very interesting post by Maria Popova on UC Berkeley psychologist Dacher Keltner's book, The Power Paradox: How We Gain and Lose Influence. Two quotes in particular struck me as they applied to our current situation as hospital epidemiologists and infection preventionists:

"The power paradox is this: we rise in power and make a difference in the world due to what is best about human nature, but we fall from power due to what is worst. We gain a capacity to make a difference in the world by enhancing the lives of others, but the very experience of having power and privilege leads us to behave, in our worst moments, like impulsive, out-of-control sociopaths"

"But in reading these alarmingly consistent studies, I had to wonder about one crucial confound(er) that remains unaddressed: People in positions of power also tend to be busier — that is, they tend to have greater demands on their time. We know from the now-iconic 1970s Good Samaritan study that the single greatest predictor of uncaring, unkind, and uncompassionate behavior, even among people who have devoted their lives to the welfare of others, is a perceived lack of time — a feeling of being rushed. The sense of urgency seems to consume all of our other concerns — it is the razor’s blade that severs our connection to anything outside ourselves, anything beyond the task at hand, and turns our laser-sharp focus of concern onto the the immediacy of the self alone."

I encourage you to read her full post and ponder how the Power Paradox might (or might not) apply to our new and larger roles in infection prevention. For example, I've noticed during discussions at national meetings and in peer-reviewed publications that we're blaming healthcare workers if they don't wash their hands or criticizing physicians if they overprescribe antibiotics. Keltner suggests that the Paradox can be handled by putting our focus on other people including empathizing, giving, expressing gratitude, and telling stories. It might seem that our focus on others (patients) might protect hospital epi folks, but what about the people we need to work with if we're to be successful - other healthcare workers?

An outbreak in slow motion

Not too many infections have crude mortality rates of 50% or more. Those that do generally inspire fear, alarm, and media coverage (see: avian influenza, Ebola). Hence my surprise that the heater-cooler device (HCD)-associated M. chimaera global outbreak has attracted so little attention in clinical, public health and media circles.

Now, over a year since Hugo Sax and his group first described the role of HCDs in invasive M. chimaera infections, this may be about to change. Why? Because today the CDC published (in MMWR) the results of whole genome sequencing from 11 patients and 5 HCDs in Iowa and two centers in Pennsylvania (the Iowa isolates were from our patients and devices). The results confirm what we’ve suspected from the beginning: this is a point source outbreak, and the likely source is the factory in Germany where the HCDs are manufactured. There are now several media outlets that have picked up the story (here's one from NY Times and one from Consumer Reports). 

In response to these findings, both CDC and FDA are making new recommendations for centers that use the implicated HCD (the LivaNova (formerly Sorin) 3T). You can read the details for yourself, but the major new recommendations are for provider and patient notification (not just for centers that have detected cases, but for all that use the devices), and from the FDA, a recommendation to remove any HCDs linked to contamination or clinical cases, and to transition away from use of the 3T model entirely (the alert states that use of 3T units manufactured prior to September 2014 “should be limited to emergent and/or life-threatening situations if no other heater cooler devices are available”). 

The problem is that the 3T has at least 60% of the HCD market, and if all hospitals stopped using them (even just those manufactured prior to September 2014), there wouldn’t be enough other units to fill the void. Also important to note: the FDA alert provides evidence that some 3T’s manufactured after September 2014 have been found to be contaminated with M chimaera. Whether the post-2014 contamination represents point-source contamination or not, it’s a huge problem and calls into question the use of the manufacture date in decision-making.

The bottom line is that the 3T is a proven bio-aerosol generator, and should not be in the same room as the operative field. No amount of focus on cleaning and disinfection, the direction of the exhaust fan, or the results of water cultures (which, as we’ve pointed out, are not actionable) changes that.

CDC Webinar on the M. chimaera outbreak

The CDC has just posted a webinar from late August on the M. chimaera outbreak, if you are interested in an overview.  It may be worth your while to look at this (or read our prior posts) this week, in anticipation of some additional information that will be coming soon (more details later this week).

The video below starts with introductions to the problem by Mike Bell and Joe Perz at CDC, than at 18:00 you can hear Chuck Daley from National Jewish discuss the clinical aspects of the outbreak, at 30:00 I discuss the local outbreak response, and at 46:00 Keith Allen provides a surgeon's perspective.

The ineradicable Mycobacterium chimaera

I’ve been on service for three weeks, limiting my blogging time—so this short update on the M. chimaera debacle is long overdue. Sorry! Two important recent “must-reads” about this global outbreak with a crude mortality rate of ~50%:

Peter Schreiber and colleagues from Switzerland report their experience trying to eradicate M. chimaera from their heater cooler units (HCUs) using an intensified cleaning and disinfection protocol (daily water changes using Pall-filtered tap water and 3% hydrogen peroxide, with biweekly 3% sodium hypochlorite (aka bleach) or paracetic acid disinfection). I’ve included part of their Figure 2 above: “No” means negative culture, “Yes” with a solid circle indicates M. chimaera growth, empty circles are other non-tuberculous mycobacteria. As you can see, M. chimaera persisted despite this intensified regimen, and cultures frequently skipped between positive and negative (and back again). This study nicely demonstrates the ineradicable nature of M. chimaera colonization in these Sorin 3T units, as well as the poor negative predictive value of a single set of HCU water cultures. Not only does a negative culture not reassure, but it takes 6-8 weeks to return—so cultures are not actionable for management of individual HCUs.

Another interesting tidbit from this article: a photo of the “housing unit” that they built to separate the HCU exhaust air from OR air and funnel it directly to the OR exhaust system (see Figure below from their article).

Finally, take a minute to read the best recent news article about this outbreak, from David Weissman at the York Dispatch. I continue to be astonished at the relative lack of media interest in this slow-motion train wreck, but in this piece the reporter clearly understands the potential ramifications of this problem, and touches on a key point: why hasn’t there been more attention to patient notification for those who were exposed to HCUs that we now know were contaminated when they left the factory?

More updates soon, as some interesting sequencing data will likely be published later this week…