Is the New SHEA-IDSA Practice Recommendation Related to Positive-Pressure Mechanical Valves Overly Broad and Under-Inclusive?

My hospital went through a three-year search to find a needleless access connector that performed according to our expectations. Our goal was to find a device that helped prevent occlusions.

Our facility had a high rate of occlusions, so our main goal was to reduce occlusions while maintaining a low bloodstream infection rate. We evaluated five different needleless access devices, which included positive, negative and neutral displacement. The first product put into use was a positive displacement device to reduce the occurrence of occlusions. In fact, it did the opposite and actually increased the total number of occlusions. We removed this device from use and evaluated another positive displacement device. This device did reduce the overall number of occlusions, but unfortunately our bloodstream infection rate increased while this device was in use. This particular device featured a recessed access port which was very difficult to disinfect. The next device evaluated was a neutral device. This device appeared to be very swabable yet it was extremely difficult to access. After a short evaluation, nursing staff decided this device was not acceptable due to the manipulation required to access the device. The concept of neutral displacement interested us so we brought in another small neutral displacement device. This neutral device leaked after multiple accesses. The mechanics of the device actually created a core (small hole) in the top after multiple accesses and so we had to stop using this device.

At the Association for Vascular Access (AVA) convention in 2007, we set out to find a new connector. Our IV team wanted a connector that could help prevent occlusions and also promote complete disinfection. We found a device that appeared to meet our needs and decided to evaluate it. The clear, positive displacement device offered a completely flat, smooth, swabable surface. We have been using this device now for more than a year and our occlusion and bloodstream infection rates have decreased substantially. In fact, we have been 13 months without any catheter-related bloodstream infections.

The reason for sharing our journey through the end cap jungle is that the Society for Healthcare Epidemiologists of America (SHEA) and the Infectious Disease Society of America (IDSA) recently released recommendations that actually state we should not routinely use positive pressure connectors with mechanical valves. Thus, the device we journeyed so long to find may not be recommended by SHEA-IDSA, as it may fall into this broad category.

The first thing that came to my mind is, how is this possible? These societies must not have tested all positive displacement devices because the one my facility uses does not have issues. In fact, our bloodstream infection rates have decreased to one of the lowest rates ever.

The SHEA-IDSA recommendation states, “Do not routinely use positive-pressure needleless connectors with mechanical valves before a thorough assessment of risks, benefits, and education regarding proper use.” (B-11) 88-91 and “Routine use of currently marketed devices that are associated with an increased risk of CLABSI is not recommended.”

The second line of this recommendation is a general statement and one that should be in routine practice at all facilities when researching/evaluating new products. However, when the second line is read with the first, one could come to the conclusion that positive pressure mechanical valves (PPMVs) are associated with an increased rate of CLABSI, and not recommended for use.

The SHEA-IDSA recommendation related to PPMVs are both overbroad and under-inclusive in suggesting that all PPMVs lead to increased risk of CLABSI and only PPMVs are implicated in an increased risk of CLABSI.

Only two of the four references cited in support of the recommendation demonstrated an increased rate of CLABSI when only a PPMV was used. In both instances, the same brand PPMV was implicated in both studies. Second, the evidence used to support these recommendations is limited and lacking the scientific control one would expect when making such a strong practice recommendation.

The recommendation lists only positive pressure and omits negative pressure, when both positive and negative pressure devices were studied in the citied references.

Maragakis, et al. report on a temporal increase with a specific PPMV. Field, et al. used the term “mechanical valve” throughout with no reference to positive pressure, but the study site used both positive and negative pressure MVs. Salgado, et al., report on an increased rate of catheter-related bloodstream infections with the introduction of a negative pressure MV. Rupp, et al., state that the specific brand of PPMV device implicated in the outbreak in their facility was also described by Maragakis.

Each study describes in detail product deficits which may be responsible for CRBSI increase:

– “MV devices have intricate access surfaces that are more difficult to disinfect than simpler split septum models. The fluid path in the MV devices has moving parts and at least one of the MV devices has internal corrugations that may serve as reservoirs and foster growth of microbial contaminates. Some of the devices have been noted by healthcare personnel to have incomplete flushing of blood from the fluid channel, and some are opaque, so that this would not be readily apparent to the user.”

– “Risk of colonization of the connector device may be higher for MV devices because of the potential difficulty in sterilizing the gap between the valve and the hub.”

– “Our findings ... suggest that the mechanical valve system could be more difficult to disinfect because of the complicated nature of the multipart device.”

– “Upon close inspection of the valve, one can observe a shallow depression and a rim between the diaphragm and the plastic housing. It is possible that microbes and debris could collect in this area, which would be relatively resistant to cleansing or disinfection. The internal mechanism of the valve contains moving parts which introduces irregularities in the fluid flow and may promote stagnation and create potential reservoirs for microbial growth. Also, the plastic housing is opaque, which prohibits visual inspection of the connector valve. Therefore, it is possible that blood or infusion products could collect within the valve and because of its opaque nature, go unnoticed by healthcare workers.”

So, is the new SHEA-IDSA practice recommendation related to positive pressure mechanical valves overly broad and under-inclusive? Yes. The recommendation only calls out positive pressure while the references studied both positive and negative pressure devices. More importantly, the evidence does not suggest that it is the pressure aspect of the connector that increases the risk. The evidence defines the risks and they are quite basic:

– Surface disinfection – can it be disinfected?

– Internal mechanics – can they be thoroughly flushed?

– Visual inspection – can you see through the device to confirm flushing?

The SHEA-IDSA recommendation would have been much more useful if it identified the well-known risks as described in the cited references, rather than making an overly broad and under-inclusive statement. As always, folks, research it yourself.

Bonnie Smith, CRNI, is with the IV therapy department at Holmes Regional Medical Center in Melbourne, Fla.