Att G.6 DIA

NHSN Dialysis Event Protocol

Dialysis Event Protocol
Introduction
In 2009, more than 370,000 patients were treated with maintenance hemodialysis in the United
States. 1 Hemodialysis patients require a vascular access, which can be a catheter or a graft or
enlarged blood vessel that can be punctured to remove and replace blood. Bacteremias and
localized infections of the vascular access site are an important cause of morbidity and mortality
in hemodialysis patients. Hemodiaylsis vascular access types, in order of increasing risk of
infection, include arteriovenous fistulas created from the patient’s own blood vessels;
arteriovenous grafts often constructed from synthetic materials; tunneled central lines; and
nontunneled central lines. Other access devices, such as catheter-graft hybrid devices, also exist.
Because of frequent hospitalizations and receipt of antimicrobial drugs, hemodialysis patients are
also at high risk for infection with antimicrobial-resistant bacteria. Measuring and tracking rates
of infection and utilizing this information is an important part of prevention.
Infection prevention information can be located at http://www.cdc.gov/dialysis/

Dialysis Event Surveillance
Summary: Each month, facilities report the number of maintenance hemodialysis outpatients
who were dialyzed on the first two working days of the month, using the Denominators for
Outpatient Dialysis form. This point prevalence is used to estimate the number of patients at
the facility who are at risk of healthcare-associated infection. Throughout the entire month, any
and all outpatients who receive maintenance hemodialysis at the facility are monitored for
dialysis events, which include IV antimicrobial starts, positive blood cultures, and evidence of
local access site infection. Each month, facilities use a Dialysis Event form to report the details
of each dialysis event that occurred among these patients. Before data can be reported, facilities
must indicate that they are reporting according to protocol by saving a Patient Safety Monthly
Reporting Plan. Completion of an Outpatient Dialysis Center Practices Survey is required
annually.
Setting: Surveillance occurs in outpatient hemodialysis centers. These centers may be attached
to or affiliated with a hospital, but should serve hemodialysis outpatients.
Population: Maintenance hemodialysis outpatients.
1

U.S. Renal Data System, USRDS 2011 Annual Data Report: Atlas of Chronic Kidney Disease and End-Stage
Renal Disease in the United States, National Institutes of Health, National Institute of Diabetes and Digestive and
Kidney Diseases, Bethesda, MD, 2010. (http://www.usrds.org/adr.htm)

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NHSN Dialysis Event Protocol

Requirements: Participating facilities are required to report data according to this protocol,
using the NHSN definitions described herein, to ensure data are uniformly reported across
participants. A minimum of 6 months of Dialysis Event (DE) surveillance at an outpatient
hemodialysis facility, indicated on the Patient Safety Monthly Reporting Plan (CDC 57.106), is
required by CDC 2. Data must be reported to NHSN within 30 days of the end of the month for
which they were collected (e.g., patient census information from September must be reported no
later than October 30).

Definitions of Dialysis Events
Dialysis Event: Three types of dialysis events are reported by users: IV antimicrobial start;
positive blood culture; and pus, redness, or increased swelling at the vascular access site. An
additional four types of dialysis events are calculated from the reported data: bloodstream
infection, local access site infection, access-related bloodstream infection, and vascular access
infection.
IV antimicrobial start: Report all outpatient intravenous (IV) antibiotic and antifungal starts,
regardless of the reason for treatment (i.e., include IV antimicrobial starts unrelated to vascular
access problems) and regardless of the duration of treatment. Report all IV antibiotic starts, not
just vancomycin. Do not report IV antiviral starts. Report outpatient starts that are continuations
of inpatient treatment.
There must be 21 or more days from the end of the first IV antimicrobial start to the beginning
of a second IV antimicrobial start for two starts to be considered separate dialysis events, even if
different antimicrobials are used. If IV antimicrobials are stopped for less than 21 days and then
restarted, the second start is NOT considered a new dialysis event. To apply the 21 day rule to
outpatient IV antimicrobial starts that are continuations of inpatient treatment, consider the start
day to be the first day of outpatient treatment.
Positive blood culture: Report all positive blood cultures collected as an outpatient or collected
within 1 calendar day after a hospital admission, regardless of whether or not the patient received
treatment. The date of a blood culture result is based on the date the blood specimen was
collected, not the date the laboratory reported the result.
There must be 21 or more days between positive blood cultures for each positive blood culture to
be considered a separate dialysis event, even if organisms are different. If positive blood cultures
occur less than 21 days apart, the second positive blood culture(s) is NOT considered a new
2

Other organizations (e.g., your ESRD Network or State Health Department) may require additional months of
reporting. Participants reporting to meet the Centers for Medicare and Medicaid (CMS) End Stage Renal Disease
(ESRD) Quality Incentive Program (QIP) rule requirements may report as few as three consecutive months of data
in 2012.

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dialysis event: add new organisms from these subsequent positive blood cultures to the first
report.
Pus, redness, or increased swelling at the vascular access site: Report each new outpatient
episode where the patient has one or more symptoms of pus, greater than expected redness or
greater than expected swelling at a vascular access site, regardless of whether the patient
received treatment. There must be 21 or more days between the onset of a first episode and onset
of a second episode of pus, redness, or increased swelling at a vascular access site to be
considered separate dialysis events. If an episode of pus, redness, or increased swelling at a
vascular access site resolves and then recurs within 21 days, the recurrence is NOT considered a
new dialysis event.
Bloodstream infection: Any positive blood culture.
Local access site infection: Pus, redness, or swelling of the vascular access site and bloodstream
infection is not present.
Access-related bloodstream infection: Positive blood culture with the suspected source
identified as the vascular access site or uncertain.
Vascular access infection: Either a local access site infection or an access-related bloodstream
infection.

Vascular Access Types
All vascular accesses are included in Dialysis Event reporting, even if they are not used for
dialysis and even if they have been abandoned and/or are non-functional.

3

•

Nontunneled central line: a central venous catheter that travels directly from the skin
entry site to a vein and terminates close to the heart or one of the great vessels, typically
intended for short term use.

•

Tunneled central line: a central venous catheter that travels a distance under the skin from
the point of insertion before terminating at or close to the heart or one of the great vessels
(e.g., Hickman® or Broviac® catheters 3).

•

Graft: a surgically created connection between an artery and a vein using implanted
synthetic tubing for the purpose to provide a permanent vascular access.

Use of trade names and commercial sources is for identification only and does not imply endorsement.

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•

Fistula: a surgically created direct connection between an artery and a vein to provide
vascular access.

•

Other access device: includes hybrid access devices (e.g., HeRO® vascular access
device3), ports, and any other central vascular access devices not meeting the above
definitions.

REPORTING INSTRUCTIONS
NHSN forms should be used to collect required data, using the definitions outlined in this
protocol. Each form has corresponding instructions which define all fields on the form.
Complete a Survey Annually: Upon enrollment and annually thereafter, complete the
Outpatient Dialysis Center Practices Survey (CDC 57.104). Annual surveys can be completed
for the year as early as the second week of January and are due on or before April 1 of the same
year.
Patient Safety Monthly Reporting Plan: The Patient Safety Monthly Reporting Plan (CDC
57.106) is used by NHSN facilities to inform CDC which Patient Safety modules are used during
a given month. There must be a Monthly Reporting Plan completed before data are entered into
NHSN for that month. Facilities participating in Dialysis Event surveillance indicate “DE” for
their ‘outpatient hemodialysis clinic’ location, under the Device-Associated section for each
month that they will be doing Dialysis Event surveillance.
For months that a facility is not participating in any Patient Safety surveillance, a monthly
reporting plan should still be completed, but the checkbox “No NHSN Patient Safety Modules
Followed this Month” is selected.
Report Denominator Data Monthly: Each month, report the number of maintenance
hemodialysis patients with each vascular access type who received hemodialysis at the center
during the first two working days of the month on the Denominators for Outpatient Dialysis
form (CDC 57.119). Report all maintenance hemodialysis outpatients, including transient
patients. Exclude non-hemodialysis patients and exclude inpatients. Report denominator data
each month, regardless of whether any dialysis events occur. Each patient is counted only
once; if the patient has multiple vascular accesses, record that patient once, reporting their
highest infection risk vascular access type only. See tables of instructions for an explanation
of each field on the Denominators for Outpatient Dialysis form.

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Report Numerator Data Monthly: Each month, complete one Dialysis Event form (CDC
57.109) per event among all patients who received hemodialysis at the facility during that month.
If a transient patient has a dialysis event during the time he or she is receiving hemodialysis
treatment at your facility, report the dialysis event. If no dialysis events occurred during a given
month, select ‘Report No Events’ on the Denominators for Outpatient Dialysis form. Complete a
Dialysis Event form only if a maintenance hemodialysis outpatient has one or more of the
following:
• IV antimicrobial start
• Positive blood culture
• Pus, redness or increased swelling at the vascular access site
See tables of instructions for an explanation of each field of the Dialysis Event form.
Reporting multiple dialysis events for a single patient: Dialysis Event surveillance definitions
include IV antimicrobial start; positive blood culture; and pus, redness, or increased swelling at
the vascular access site. If multiple dialysis events occur together, as a part of the same patient
problem, they should be reported as one dialysis event. For example, if a patient has a positive
blood culture and begins IV antimicrobials, these two events would be recorded together on one
form. When reporting multiple dialysis events together, always use the date from the first event
that occurred. Refer to dialysis event definitions for the 21 day rule. Do not report unrelated
dialysis events on the same form.
Suspected source of the positive blood culture: When reporting a positive blood culture,
indicating one of four suspected sources of the positive blood culture is required.
Vascular access: Choose “Vascular access” if there is objective evidence of vascular
access infection and the vascular access is thought to be the source of the positive
blood culture.
A source other than the vascular access: Choose “A source other than the vascular
access” if either (a) or (b) is true:
a) a culture from another site (e.g., infected leg wound, urine) shows the same
organism found in the blood and the site is thought to be the source of the
positive blood culture
b) there is clinical evidence of infection at another site which is thought to be the
source of the positive blood culture, but the site was not sampled for culture
Contamination: Choose “Contamination” if the organism isolated from the blood culture
is thought by the physician, infection preventionist, or head nurse to be a
contaminant. Contamination is more likely if the organism is a common
commensal and is isolated from only one blood culture.

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Examples of some common commensals include:
o diphtheroids [Corynebacterium spp., not C. diphtheriae]
o Bacillus [not B. anthracis] spp.
o Propionibacterium spp.
o coagulase-negative staphylococci [including S. epidermidis]
o viridans group streptococci
o Aerococcus spp.
o Micrococcus spp.
Uncertain: Choose “Uncertain” only if there is insufficient evidence to decide among the
three previous suspected source categories.
Data Analyses: Dialysis event rates are stratified by vascular access type and expressed per
100 patient-months. Rates are calculated by dividing the number of events by the number of
patient-months and multiplying the result by 100. CDC calculates pooled mean rates for each
event type by combining rates from all participating facilities. Facilities can compare their
rates with the pooled mean rates using NHSN analysis rate table output options. Facilities are
strongly encouraged to analyze the data they report and provide regular feedback to staff about
performance.
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× 100
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Reporting Resources
Data collection and reporting resources, including Frequently Asked Questions (FAQs), are
available on the NHSN Dialysis Event website, http://www.cdc.gov/nhsn/psc_da_de.html
Please direct questions to the NHSN Helpdesk at [email protected]

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