An optimal solution
In the course of the meeting, the panel elaborated on
the criteria that would be required for an effective
system that limits the risk of misconnections. Such
a solution must deliver accurate doses for all dosage
volumes and medication forms for all patients,
regardless of age or size. The system must be safe – its
design and implementation must not increase risk.
Evidence is required demonstrating that the design
reduces the risk of misconnections and maintains
dosing accuracy without substantially altering routine
workflows. Finally, the ideal system would work
across all systems, including in-patients, outpatients,
long-term care, and community settings. The panel
used these criteria to evaluate proposed enteral
system designs.
An enteral device has come to market that
conforms to the ISO standard, and is significantly
different from traditional syringe design. The female
ISO syringe design known as ENFit ® * places enteral
connectors in a non-traditional female-to-male
orientation. The syringes have a female connector
that fits around the male connector at the end of
the feeding tube. While this new design resolves
some of the risks of tubing misconnections, there
may be unintended consequences. Alternatively,
a male enteral syringe design known as the RightFit
system is in development that does not change
the orientation of the connections, and is similar
to traditional syringes in design, function, and
performance, while conforming to ISO standards.
The panel had the opportunity to assess both
designs. They provided the European perspective
on patient safety with enteral syringes, gave expert
feedback on the alternative enteral syringe designs,
and evaluated how the proposed solutions would fit
into various health care settings. The proceedings
from the meeting follow in this report.
The female syringe design
Dose inaccuracy
A variety of concerns with the proposed female
design, called ENFit ® , were highlighted. Dose
inaccuracy was a major concern. The female syringe,
because of its wider tip design and the resulting
dead space, increases variability which can be
clinically significant especially with drugs that have
a narrow toxic therapeutic index and in critically
ill patients (e.g. preterm infants). Important to note
that this also applies to the male design; there is
thus a gap as there is no ISO standard mandating
the accuracy of graduations on female /male oral
enteral devices. Further, external laboratories have
not found the dose accuracy claims for the female
syringes to be reproducible, and medicines that
require small-dose increments have not been tested
with the syringes.
Training and usage challenges
The lack of dose reproducibility highlights another
concern with the female design: achieving even
±10% dose accuracy requires rigorous adherence to
detailed procedures. This introduces a high degree
of variability where standard practice should be the
goal. Panellists pointed out that institutions have
an ever-changing group of providers with varying
levels of expertise. Providing adequate training
poses additional costs and burdens. Furthermore,
education, while essential, is less effective in reducing
risk than appropriate engineering and design.
“It is not always the same nurse that is taking
care of a specific patient. So, it is not just the
correctness/accuracy of dose calculation but also
the uniformity of practice by different personnel.”
ENFit ® doesn’t
feel any safer.
UK Nurse
Complexity
A second concern is the complexity of the ENFit ®
system, which requires the use of adaptive pieces
and parts to achieve dose accuracy. All pieces and
parts may not be readily available in all settings,
and this can encourage work-arounds. The female
syringes cannot be used for all patients in all
settings, and appear to have limited adaptability
in paediatric settings, the panel noted. Complexity
is the enemy of safety and accuracy.
The panel observed that the required add-on
pieces, including bottle adaptors and straws, were
designed to prevent some errors or overcome
limitations of the female design. But there were
added costs associated with these add-on pieces, as
well as additional risks such as choking hazards, the
potential for medicine to accumulate in the syringe
tip (required to be cleared for the female low dose
tip), inconsistent use of the adaptors, a requirement
for many different adaptors for different bottles, and
lack of adherence to the specific practices required.
The need for a specific cleaning brush and
cleaning protocols to clean the ENFit ® tube raised
concerns that the male tube end may accumulate
drips from medication or nutrition and become
a source of microbial contamination. New
procedures have to be developed to remove
bioburden and reduce risk of microbial growth,
which adds tasks and documentation.
Changing the workflow
There also is risk and cost associated with changing
a highly routine workflow and replacing it with
several parallel – but exclusive – workflows. If the
appropriate syringe or necessary components are
hospitalpharmacyeurope.com | 2019 | Issue 91 | 33