We have precious little data on what works to prevent the transmission of MDR-GNR. An interesting article published recently in CID provides invaluable data that an infection control programme aimed at reducing MRSA (and succeeding) was also effective in reducing GNR BSI!
Preventing HCAI: go long or go wide?
There seems to be a general movement away from targeted, pathogen-based precautions (principally screening and isolation) in the USA. This changing professional opinion was clear from the recent SHEA conference, where several leading experts gave what amounted to a collective justification for abandoning contact precautions for MRSA.
The update of the SHEA Compendium of Strategies to Prevent Healthcare-Associated Infections in Acute Care Hospitals is accompanied by a commentary from a group of leading US figures titled ‘Approaches for preventing HCAI: Go long or go wide’. In the commentary, the authors weigh the evidence and opinion for so-called ‘vertical’ (aka targeted) vs. ‘horizontal’ (aka universal) interventions (Table).
Table: Go long or go wide? Examples of targeted and universal interventions (adapted from Wenzel & Edmond, via Septimus et al.).
The commentary outlines the potential drawbacks of targeted approaches (such as fewer visits from healthcare workers and feelings of isolation), but doesn’t spend a lot of time discussing the potential drawbacks of universal approaches. For example, “isolation fatigue”, where a procedure loses its impact if it has to be applied to every patient. And then there’s the possibility of resistance when performing universal decolonization. This is particularly worrysome when using antibiotics, but could also be a problem when using biocides such as chlorhexidine.
I’m not ready to abandon pathogen-based targeted interventions just yet. Conceptually, it just does not make sense. If you have a patient with MRSA and a respiratory virus, chances are they will become a ‘super-spreader’. Those who favour universal approaches do make some provision for exceptional cases that really should be identified and isolated via a ‘syndromic’ approach to isolation: crudely, only isolate patients when they’re oozing. However, this syndromic approach would likely miss our ‘super-spreading’ patient, which may well result in an MRSA outbreak – that we could all do without.
Furthermore, if you have a patient who is colonized with CRE, are you brave enough to take no special precautions, as would be the case for a ‘universal only’ approach? The success of this strategy would depend on a high level of compliance with standard precautions such as hand hygiene and environmental cleaning and disinfection. Whilst sound in theory, this just doesn’t happen in the trenches; your facility is above average if your hand hygiene compliance rate is the right side of 40%. Whilst still not 100%, hand hygiene compliance is higher when patients are placed in isolation, most likely because there’s a stronger psychological trigger to comply with hand hygiene.
It’s important to note that targeted and universal approaches are by no means mutually exclusive. For example, on our ICU in London, we have been using universal chlorhexidine decolonization for a decade combined with targeted screening and isolation, and have seen a dramatic reduction in the spread of MRSA.
So, should we go long or go wide in the prevention of HCAI? The answer is both. We should optimize case for all patients, which means careful standard precations with liberal application of chlorhexidine and tight restriction of antibiotics. But we should also identify those with communicable pathogens and segregate them from others. In this regard, we have the weight of history on our side.
Image: Jeff Weese.