NHSN Significant Changes to the Patient Safety Component – 2017
This Quick Learn will address significant changes that have been made to the National Healthcare Safety Network, NHSN, Patient Safety Component’s …
This Quick Learn will address significant
changes that have been made to the National
Healthcare Safety Network, NHSN, Patient Safety
Component's healthcare-associated infection
definitions for 2017.
NHSN Infection definitions are updated, when
necessary, to respond to feedback provided
by users, and to remain current with diagnostic
NHSN strives to be receptive and responsive
to concerns from those who apply the definitions.
The degree to which the definitions reflect
clinical determinations and also accurately
measure the success of prevention efforts
are weighed when changes are considered.
If a change is warranted, there are three
goals: to ensure that the data elements that
comprise the definition can feasibly be collected,
that they are objective and can be used consistently,
and that they are based on published scientific
findings, when possible.
For 2017, changes can be categorized into
those that pertain to: 1) updating the NHSN
organism lists, 2) the bloodstream infection,
or B-S-I surveillance module, 3) the surgical
site infection surveillance module, or changes
to definitions of infections which are used
to identify organ/space surgical site infections,
or to identify primary sites of infection
for secondary BSIs.
These definitions and changes are found in
what is commonly referred to as "Chapter17"
of the NHSN Patient Safety Component Manual.
The organism lists that are used NHSN to report
events were updated for January, 2017.
The lists that were updated include All Organisms;
Mucosal Barrier Injury-Laboratory Confirmed
Bloodstream Infection, or MBILCBI; and
Common Commensal, or CC.
Many new organisms have been identified since
the last NHSN organism list update, and some
organisms have undergone changes related to
classification and categorization in the microbial
NHSN made the decision to continue to include
organisms in the MBIL CBI or CC lists if
their previous name was included on the list.
Organisms were included on these lists based
on their genus name, not their species name.
By adopting these rules, the MBIL CBI list
expanded by doubling both individual organisms,
as well as genera.
The CC list nearly doubled the number of genera,
while expanding by over 100 individual organisms.
It's important that facilities reference
the 2017 MBIL CBI and CC lists when determining
if a healthcare-associated infection event
criteria is met.
These lists can be found on the NHSN website,
under Supporting Material.
Specific to BSI surveillance, and similar
to what was done in 2016 with Salmonella,
NHSN has excluded the following pathogens
for use in primary BSI determination: Campylobacter,
Clostridium difficile, enteropathogenic Escherichia
coli, Shigella, Listeria, and Yersinia.
It would be highly unlikely for these organisms
to cause primary BSIs, especially central-line
They may be reported as causative agents for
gastrointestinal infections, and may result
in a secondary bloodstream infection, but
they should not be reported as primary BSIs.
Another BSI exclusion, is related to early
onset Group B Streptococcal infections occurring
Group B Streptococcus will not be reported
as a causative agent for a central line-associated
BSI during the first six days of life.
Early onset infection with this type of organism
is often the result of transmission from mother
to child during labor and birth and not associated
with the use of a central line.
If the infection occurs on day three through
day six, of hospitalization, the BSI will
still be considered a healthcare-associated
BSI, but the BSI will not be associated with
the central line nor reported as a CLABSI.
In regards to patients accessing their own
intravenous lines, the word accession has
been changed to injection in the NHSNBSI protocol.
BSIs may be excluded as central line-associated
if there is documentation during the BSI's
infection window period that the patient was
observed or suspected of injecting into his
This modification was made to clarify the
intent of the exclusion, as NHSN users sometimes
had difficulty understanding the meaning of
the word accession.
Each year the Centers for Medicare and Medicaid
Services, or CMS, updates their procedural
codes for International Classification of
These codes are currently in their 10th revision,
and are called the ICD ten PCS codes.
Each year the codes must be reviewed and assigned
to the appropriate NHSN operative procedure
categories for use in Surgical Site Infection,
or SSI, surveillance.
It takes time to properly review and consider
updates and revise the NHSN application.
For this reason, ICD-ten PCS codes included
in the CMS Fiscal Year 2017 Final Rule, released
in October 2016, are not included in the NHSN
operative procedure categories.
The mapping of these codes is about a year
behind the CMS updates so they will be included
in the 2018 NHSN update.
The current NHSN Operative Procedure Categories
and associated codes are included in the mapping
documents located here.
Please visit the website to consider the changes
if your facility is reporting SSI data.
Please note that your facility's coders
may be assigning codes included in the CMS
Fiscal Year 2017 Final Rule for operative
procedures performed on or after October 1,
However, facilities enrolled in and reporting
through NHSN should use the list of operative
procedure codes found on the NHSN SSI webpage
and referenced in the NHSN 2017 SSI Protocol
for categorizing their SSI procedures for
There have been modifications made to some
of the infection definitions found in Chapter
17 of the NHSN manual entitled, "CDC NHSN
Surveillance Definitions for Specific Types
These definitions are used to identify specific
types of organ/space surgical site infections.
They are also used to determine if a primary
site of infection is present, to which a BSI
may be attributed as secondary.
Some facilities monitor the types of infections
found in this chapter.
Prior to 2017, the previous NHSN gastrointestinal,
or GIT criterion 2c, did not limit the organisms
which could be identified in the bloodstream.
Criterion 2c is modified for 2017 as seen
here in orange.
Note that criterion 2c now requires that in
addition to the presence of at least 2 signs
and symptoms, and an imaging test result indicating
infection of the GI tract, at least one Mucosal-Barrier
Injury organism must be identified in the
This modification increases the consistency
between the Intra-abdominal, or IAB, Infection
and GIT definitions.
In 2017, NHSN added guidance to the ORAL infection
3a criterion which was mistakenly omitted
When meeting criterion 3a with organisms identified
from a specimen, the specimen must be mucosal
scrapings or exudate.
Guidance has also been included in the criteria
for defining lung infection spinal abscess,
or SA, and necrotizing enterocolitis or NEC.
Clinical correlation is allowed to confirm
an imaging test that is otherwise equivocal,
or not certain, for infection.
In criteria where imaging test evidence of
infection is used as an element, for test
results indicating possibly but not definite
infection, supportive clinical correlation,
can be used to fulfill that requirement.
For these purposes, clinical correlation means
there is documentation in the medical record
that the patient is receiving antimicrobial
therapy for that type of infection.
Perhaps one of the most significant changes
made by NHSN involves the endocarditis, or ENDO,
Endocarditis is a disease process which sometimes
requires an extended amount of time for diagnosis;
this time period can extend beyond the NHSN
Infection Window Period of seven days.
Additionally, a prolonged treatment period
is sometimes necessary to resolve endocarditis.
During this time, blood specimens may remain
positive for organisms.
Standard diagnostic and treatment guidelines
suggest on-going testing of the blood for
clearance of infection.
For these reasons, the Infection Window Period,
the Repeat Infection Timeframe, and the Secondary
Bloodstream Infection Attribution Period have
all been extended for ENDO.
The Infection Window Period is 21 days rather
than seven, and will include the date of the
diagnostic test, as well as 10 days before
All elements of the ENDO criterion must be
met during this 21-day period.
This completes this NHSN Quick Learn program
related to updates to the NHSN Patient Safety
Component's healthcare-associated infection
definitions for 2017.
Please send questions or feedback to NHSN
at CDC dot gov.