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Cluster-Randomized Trial of Devices to Prevent
Catheter-Related Bloodstream Infection
Steven M. Brunelli,1 David B. Van Wyck,2 Levi Njord,2 Robert J. Ziebol,3 Laurie E. Lynch,3and Douglas P. Killion3
1
DaVita Clinical Research, Minneapolis, Minnesota; 2DaVita, Inc., Denver, Colorado; and 3Pursuit Vascular, Inc., Maple
Grove, Minnesota

ABSTRACTCentral venous catheters (CVCs) contribute disproportionately to bloodstream infection (BSI) and, byextension, to infection-related hospitalization, mortality, and health care costs in patients undergoing
dialysis. Recent product advancements may reduce BSIs, but a sufﬁciently powered comparative-effectiveness study is needed to facilitate evidence-based patient care decisions. In a 13-month, prospective,
cluster-randomized, open-label trial, we compared BSI rates in facilities using ClearGuard HD antimicrobial
barrier caps (ClearGuard group) with those in facilities using Tego hemodialysis connectors plus Curos
disinfecting caps (Tego+Curos group). Forty DaVita dialysis facilities in the United States were pairmatched by BSI rate, number of patients using CVCs, and geographic location, and then cluster randomized 1:1. We enrolled all adult patients undergoing dialysis with CVCs at these facilities, except thoseallergic to heparin or chlorhexidine. Overall, 1671 patients participated in the study, accruing .183,000
CVC-days. The study outcome was positive blood culture (PBC) rate as an indicator of BSI rate. We calculated results at the cluster level and adjusted for the facility cluster effect. During a 3-month run-in period
immediately before study interventions, the groups had similar BSI rates (P=0.8). During the 13-monthintervention period that immediately followed, the ClearGuard group had a BSI rate signiﬁcantly lower
than that of the Tego+Curos group (0.28 versus 0.75 PBCs per 1000 CVC-days, respectively; P=0.001). No
device-related adverse events were reported. In conclusion, compared with Tego connectors plus Curos
caps, ClearGuard HD antimicrobial barrier caps signiﬁcantly lowered the rate of catheter-related BSIs inpatients undergoing hemodialysis using CVCs, representing an important advancement in hemodialysis
patient care.
J Am Soc Nephrol 29: 1336–1343, 2018. doi: https://doi.org/10.1681/ASN.2017080870

Central venous catheters (CVCs) are used in only 19%
of dialysis procedures in the United States, but are
responsible for 70% of vascular access–related bloodstream infections (BSIs).1 In addition, BSI is thesecond leading cause of death among patients undergoing hemodialysis who use CVCs for their vascular

Received August 11, 2017. Accepted February 1, 2018.
Published online ahead of print. Publication date available atwww.jasn.org.
Correspondence: Robert Ziebol, Pursuit Vascular, Inc., 6901 E
Fish Lake Road, Ste 166, Maple Grove, MN 55369. Email: rziebol@
pursuitvascular.com
Copyright © 2018 by the American Society of Nephrology

1336

ISSN : 1046-6673/2904-1336

Signiﬁcance Statement
Catheter-related bloodstream infections are a common
complication related to hemodialysis central venous
catheter (CVC) use and they contribute to increased
infection-related hospitalization, mortality, and healthcare costs. Devices are currently available that aredesigned to reduce these infections, but publishedcomparative effectiveness data are needed to allow
evidence-based patient care decisions. This manuscript
describes a large, multicenter, randomized clinicalstudy in a real-world setting. The results show that use of
ClearGuard HD Antimicrobial Barrier Caps, whencompared with Tego connectors plus Curos caps, results in a signiﬁcantly lower rate of catheter-related BSIs
in patients undergoing hemodialysis using CVCs. This
represents an important advancement in hemodialysis
patient care for patients dialyzing with CVCs.

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access. Devices are now available that may signiﬁcantly reduce
BSI rates. However, comparative effectiveness data for these devices have not been available to allow evidence-based patientcare decisions.
This randomized comparative-effectiveness study evaluated
two interventions designed to mitigate the risk of catheter-related
BSI: ClearGuard HD Antimicrobial Barrier Cap (Pursuit Vascular, Inc.), versus the combination of Tego Needlefree Hemodialysis Connector (ICU Medical, Inc.) used in combination with
Curos Disinfecting Cap for Tego (3M Healthcare). These devices
are hereinafter referred to as the ClearGuard, Tego, and Curos,
respectively.
The devices studied are shown in Figure 1 and modes of action
are summarized in Table 1. ClearGuard is used in the same manneras a standard CVC cap. However, ClearGuard has a rod and threads
containing a dry chlorhexidine coating. Once the cap is attached tothe catheter hub, the dry chlorhexidine coating dissolves into thelock solution proximal to the clamp to kill .99.99% of common
pathogenic organisms.2 Because chlorhexidine is an antibiotic-free
antimicrobial, the risk for developing resistant organisms is low
compared with antibiotics.3,4 ClearGuard was previously shownto signiﬁcantly lower catheter-related bloodstream infection(CRBSI) rates when compared with standard CVC caps ina prospective randomized study of 2470 patients receiving
hemodialysis.5
Tego is designed to prevent bacteria from getting inside the
CVC using a mostly “closed” system.6 Tego was previously
evaluated in a retrospective study, which concluded that
Tego may reduce the risk of CRBSI.7 For additional protection,
Curos is used with Tego. Curos kills organisms on the outside
surface of Tego using 70% isopropanol alcohol. Curos waspreviously shown in vitro to kill infection-causing organisms.8,9The combination of Tego+Curos was used in this study because itis expected to perform better than Tego alone. ClearGuard isdesigned to kill bacteria inside and outside the catheter hub,whereas Tego+Curos kills bacteria on the outside only.

CLINICAL RESEARCH

facilities remained in the study throughout its duration. All
patients with CVCs dialyzing in participating facilities wereenrolled in the study with the exception of nine who were
excluded due to history of heparin allergy (none were excluded
for chlorhexidine allergy). A ﬂow diagram for enrollment is shownin Figure 2. There were no protocol deviations or device-related
adverse events reported during the study. There was one protocol
change to increase the intervention period from 12 to 13 months.
A total of 627 patients (304 ClearGuard, 323 Tego+Curos)
qualiﬁed for primary analysis of the run-in phase of the study.
Characteristics of participants in the two study groups (Table2) were reasonably balanced, with the exception of race (35%versus 46% black, respectively; omnibus P=0.02) and diabetes(55% versus 64%, respectively; P=0.02).
A total of 1671 patients (826 ClearGuard, 845 Tego+Curos)
qualiﬁed for primary analysis of the intervention phase of thestudy. Again, characteristics of participants were reasonably
balanced (Table 2) with the exception of age (63.7 versus 62.0
years, respectively; P=0.02) and race (32% versus 42% black,respectively; omnibus P,0.001).
Primary Analysis

Run-In Period
During the 3-month run-in period, 18 positive blood cultures(PBCs) occurred during 18,739 CVC-days in the ClearGuard
group, and 22 PBCs occurred during 20,454 CVC-days in the
Tego+Curos group, corresponding to rates of 1.02 and 1.08 per1000 CVC-days, respectively. Between-group differences inrates were nonsigniﬁcant (P=0.8).
Intervention Period
During the 13-month intervention period, 23 PBCs occurred
during 83,064 CVC-days in the ClearGuard group, and 75
PBCs occurred during 100,042 CVC-days in the Tego+Curos
group, corresponding to rates of 0.28 and 0.75 PBCs per 1000
CVC-days, respectively. Twenty-one and 63 unique patients
experienced PBCs, respectively. The incidence rate ratio (IRR)
was 0.37 (P=0.001) favoring ClearGuard (Figure 3A, Table 3).

RESULTS
Exploratory Analyses
Patient Flow and Demographics

CRBSI Analysis
The term CRBSI, as used in the literature, ranges from surveillance deﬁnitions (all PBCs occurring in patients with CVCs) torigorous clinical deﬁnitions (deﬁned by
precise laboratory ﬁndings identifying the
CVC as the source of the infection).10,11 In
this study, the link between the PBC and atrue CVC-related BSI is as follows. The
analysis, CRBSI is deﬁned as: (1) analysis
is performed on a per-patient basis (maximum of one PBC per patient) to ensure no
duplicate counting of the same infection;
Figure 1. ClearGuard is a single-piece design that applies antimicrobial inside and (2) to better ensure that PBCs were related
outside the CVC hub versus Tego+Curos, which is a two-piece design that applies to the CVC, only PBCs designated as access-related on the National Healthcare
antimicrobial only to the outside of the Tego.
Forty dialysis facilities were enrolled in the study, with 20 in
the ClearGuard group and 20 in the Tego+Curos group. All

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Table 1. Modes of action for the ClearGuard HD cap, Tegoconnector, and Curos cap
Attribute
Kills bacteria inside of hub
Kills bacteria on outside of hub“Closed” system (opened once per week)

ClearGuard Tego Curos
✓
✓

✓
✓

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Safety Network (NHSN) forms of patients with CVCs were
included; (3) to help rule out skin contamination, only PBCs
with recognized pathogens (no common commensals) were
included; and (4) PBCs with polymicrobial growth were excluded because this may be an indication of contamination.
The denominator is the number of days at-risk per study protocol. The resulting IRR was 0.37 (P=0.003) favoring ClearGuard (Figure 3B, Table 3).
Central Line–Associated Bloodstream Infections Analysis
The central line–associated bloodstream infections(CLABSI) analysis was on the basis of the NHSN CLABSI
deﬁnition.12 In this analysis, the PBC (numerator) must either be (1) a recognized pathogen and not related to an infection at another site, or (2) a common commensal fromtwo blood draws, not related to an infection at another site,and patient has at least one of: fever, chills, or hypotension.
The denominator is the number of days at-risk per study
protocol. The resulting IRR was 0.35 (P=0.003) favoring
ClearGuard (Figure 3C, Table 3).
Access-Related Bloodstream Infections Analysis
The access-related bloodstream infections (ARBSI) analysis
was on the basis of the Center for Disease Control (CDC)
NHSN deﬁnition for ARBSI.13 The numerator is PBCs withthe suspected source reported as the vascular access or uncertain. The denominator is the number of days at-risk per study
protocol. The resulting IRR was 0.32 (P,0.001) favoring
ClearGuard (Figure 3D, Table 3).
Organism Analysis
ARBSI events were analyzed according to organism type.
When considering only ARBSIs comprising Gram-positive
organisms, the IRR was 0.40 (P=0.01) favoring ClearGuard(Figure 3E, Table 3). For ARBSIs comprising only Gram-negative organisms, the IRR was 0.19 (P=0.001) favoring ClearGuard (Figure 3F, Table 3). There were too few fungi PBCs toperform an analysis (no events in the ClearGuard group). The
IRR for multidrug resistant organisms was 0.60 (P=0.5); there
were 4 PBCs in the ClearGuard group and 8 PBCs in the Tego
+Curos group.
De Novo CVCs Analysis
To account for potential latent effects due to colonization ofcatheters before entering the study, a subgroup analysis
was performed among patients entering the study with a1338

Journal of the American Society of Nephrology

Figure 2. Flow of subjects through the study. (A) Run-in and (B)intervention periods.

new CVC (called de novo CVC); thus, all patients in thissubgroup start with a CVC vintage of zero. The resulting
IRR was 0.28 (P,0.001) favoring ClearGuard (Figure 3G,
Table 3).
Sensitivity Analysis—No Initial 21-Day Censor
Because of the biologic latency between CVC inoculation andeventual BSI, the primary analysis did not consider infections
that occurred within 21 days of patient start (Figure 4), andthereby also excluded patients who had ,21 CVC-days. To
understand potential implications of this a priori analytic
choice a sensitivity analysis was conducted in which all patients with CVCs were considered from their study start.
The resulting IRR was 0.35 (P=0.002) favoring ClearGuard(Figure 3H, Table 3).
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CLINICAL RESEARCH

Table 2. Patient demographics during the run-in and intervention periods

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Characteristic
Run-in period (Aug 2015–Oct 2015)
No. of facilities
No. of CVC patients
Age, yr
Sex (% men)
Race
White
Black
Hispanic
Other
Missing
Diabetes
Dialysis vintage, yr
Intervention period (Nov 2015–Nov 2016)
No. of facilities
No. of CVC patients
Age, yr
Sex (% men)
Race
White
Black
Hispanic
Other
Missing
Diabetes
Dialysis vintage, yr

All

ClearGuard Group

Tego+Curos Group40
627
62.9615.6
308 (49)20
304
63.7615.6
145 (48)20
323
62.2615.5
163 (50)255 (41)256 (41)73 (12)43 (7)0 (0)376 (60)
2.263.9133 (44)107 (35)37 (12)27 (9)0 (0)168 (55)
2.264.2

122 (38)149 (46)
36 (11)16 (5)0 (0)208 (64)2.263.6

40
1671
62.8614.9
856 (51)20
826
63.7614.4
421 (51)20
845
62.0615.3
435 (51)778 (47)621 (37)
171 (10)98 (6)3 (0)998 (60)
1.763.2

414 (50)267 (32)
83 (10)60 (7)2 (0)477 (58)
1.663.3

364 (43)354 (42)88 (10)38 (5)1 (0)521 (62)
1.863.2

P Value

0.2
0.5
0.02

0.02
0.9

0.02
0.8
,0.001

0.1
0.2

Values for categoric variables are given as number (percentage); values for continuous variables, as mean6SD.

Intravenous Antibiotic Analysis
An analysis was performed to investigate whether an increasein antibiotic use could be responsible for the decreased infection rates. The rate of intravenous (IV) antibiotic starts decreased by 0.6 per 1000 CVC-days from run-in period tointervention period, with the greatest decrease in the ClearGuard group. In addition, an analysis was performed to investigate whether there was a corresponding decrease in therate of IV antibiotics associated with PBCs. The resulting IRR
was 0.37 (P,0.001) favoring ClearGuard (Figure 3I, Table 3).
Other Analyses
Additional exploratory analyses were performed to observe
trends in areas where the study was not designed to have sufﬁcient
power. CVC exchange rate was not statistically different in the
ClearGuard group versus Tego+Curos (0.94 versus 1.03 per 1000
CVC-days, respectively; P=0.8). CVC removal rate was similar
between the two groups (7.57 versus 7.56 events per 1000 CVCdays, respectively; P=0.9). Thrombolytic use rate was not significantly different between the two groups (1.84 versus 1.89 per1000 CVC-days, respectively; P=0.9). Hospital admissions for
BSI were analyzed using the dialysis facilities’ records of admission (no other hospital records were available); the rate of hospitalizations for BSI was lower in the ClearGuard group versus
Tego+Curos (0.06 versus 0.11 per 1000 CVC-days, respectively),
but the difference was not statistically signiﬁcant (IRR=0.55;
P=0.5). There were no deaths within 30 days of a PBC in the
J Am Soc Nephrol 29: 1336–1343, 2018

ClearGuard group, and three deaths in the Tego+Curos group;
however, these results were statistically insigniﬁcant.
Lock solutions were not required to be reported. However,they were recorded in 33% of all procedures. Within bothgroups, the vast majority (.95%) of procedures used saline
as the lock solution.
DISCUSSION

This study demonstrated that use of ClearGuard resulted in asigniﬁcantly lower BSI rate versus use of Tego+Curos.
During the 3-month run-in period, there was no statisticaldifference in PBC rates between the two groups. This suggeststhat groups were well balanced in terms of BSI risk and thatdifferences in BSI rates seen during the intervention phase of
the study can be more conﬁdently ascribed to study interventions. The BSI rates were lower during intervention period versus run-in period in both groups, which is expected
because ClearGuard and Curos are both designed to reduce
BSI rates.
This study’s primary analysis, along with the exploratory
analyses, demonstrated that in a real-world hemodialysis setting use of ClearGuard was superior to use of Tego+Curos at
reducing PBCs, CRBSI, CLABSI, Gram-positive infections,Gram-negative infections, and IV antibiotic starts related to
PBCs in patients undergoing hemodialysis using CVCs.
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CLINICAL RESEARCH

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conﬁned proximally to the CVC clamp,
thus being prevented from entering thebloodstream as occurs with antimicrobial
lock solutions18,19; (2) ClearGuard dose isﬁxed, thus eliminating risk of lock solution
misadministration and the associated complications of dysgeusia and even death20–25;(3) ClearGuard antimicrobial is antibioticfree so the risk of developing drug-resistantorganisms is presumably lower than with
antibiotic locks; and (4) ClearGuard is FDA
cleared for use in patients receiving hemodialysis and may be used with heparin, saline, or citrate lock solution.2
The study results are likely broadly generalizable to United States dialysis facilities
because (1) this study was conducted in areal-world manner with broad inclusionary requirements, (2) the control group
Figure 3. Study results demonstrate that ClearGuard caps are superior to Tego was formidable (Tego+Curos using best+Curos for reducing bloodstream infection across all nine analyses. Summary of IRRs practice infection prevention techniques),(dots) and 95% conﬁdence intervals (whiskers), ClearGuard facilities versus Tego (3) the ClearGuard performance is consis+Curos facilities, for (A) primary analysis and (B–I) exploratory sensitivity analyses. tent with an independent study conducted
Estimates,1 favor ClearGuard.
at another large dialysis provider using a
different control group,5 and (4) the primary
results are consistent with the exploratory
analyses which scrutinized potential contamination, sources ofA de novo subgroup analysis considered comparative effects
infection, and censoring effects.
of the study interventions in the context of newly placed
Our ﬁndings demonstrate that ClearGuard caps are statisCVCs. Such a scenario may be a better indicator of the effects
tically superior to Tego+Curos for reducing CRBSI, representof interventions if each were adopted as standard of care (i.e.,
ing an important advancement in improved patient care.
whereby over time all CVCs would be treated with the ascribedintervention from the outset). Although the effects in this subgroup cannot be formally compared with the effects of the
primary analysis, it is reassuring that effects were at least as
CONCISE METHODS
great and, in fact, numerically more potent (IRR=0.28;
P,0.001).
DesignIn the primary analysis, at-risk time began 21-days after ﬁrst
This was a prospective, cluster-randomized comparative effectivereceipt of study intervention. This choice was prespeciﬁed andness trial of ClearGuard versus Tego+Curos among patients dialyzing
was adopted to account for biologic latency of infections parwith CVCs.
ticularly in the setting of preexisting CVCs. Nonetheless, it is
The study was conducted at 40 dialysis facilities. All facilities had
reassuring that the comparative beneﬁt of ClearGuard was at
previously used Tego before inclusion in the study. Also, all facilities
least as great (IRR=0.35; P=0.002) in a sensitivity analysis in had indicated willingness to adhere to treatment allocation uponwhich the 21-day lagged start of at-risk time was not used andeventual randomization and all underwent a 30-minute training sesall patients were considered from the ﬁrst date of study insion describing procedures necessary to both study arms.
tervention.
These 40 facilities were pair matched on the basis of: (1) prestudy
Randomized clinical trials have been conducted using anBSI rate, as reported to the CDC NHSN from February to July of
2015; (2) the number of patients with a CVC; and (3) geographic
timicrobial and antibiotic lock solutions.14–17 This study islocation. Within each matched pair, one facility was randomly allosubstantially larger than the referenced analyses (.3.53
cated to ClearGuard and the other to Tego+Curos using a computerlarger than the largest individual referenced study and .23
generated algorithm.
larger than either meta-analysis). Although observational
The unit of randomization was the facility and all eligible patientscomparisons to external populations are not ideal, it is reafwithin the study were treated according to the corresponding interﬁrming to note that ClearGuard results are comparable to thevention. Eligible patients were those who dialyzed using a CVC. Bebest lock solutions (rate=0.28 versus 0.34 per 1000 CVC-daysin ClearGuard versus Liu meta-analysis, respectively), but yond this, exclusions were made only for known hypersensitivity toheparin (nine patients) or to chlorhexidine (none).
with several advantages: (1) ClearGuard antimicrobial is1340

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CLINICAL RESEARCH

Table 3. Summary of analyses results: ClearGuard facilities versus Tego+Curos facilities, for primary analysis and exploratory
sensitivity analyses
Clinical Study Results and Exploratory Analyses

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Variable

Number of patients inanalysis
Combined
ClearGuard
Tego+Curos
Cumulative duration(CVC-days)
Combined
ClearGuard
Tego+Curos
Number of events
Combined
ClearGuard
Tego+Curos
Event rate (events per1000 CVC-days)
Combined
ClearGuard
Tego+Curos
IRR
95% LCI
95% UCIP valuePrimary
CRBSI
AnalysisAnalysis(All PBC)

CLABSI
Analysis

ARBSI
Analysis

ARBSI
Analysis,Gram-Positive
Organisms

No Initial IV Antibiotic
ARBSI
StartsDe Novo
21-d
Analysis,
CVC
Censoring within 3 d
Gram-Negativeof a PBC
Analysis Analysis
Organisms
Analysis(All PBC)

1671
826
845

1671
826
845

1671
826
845

1671
826
845

1671
826
845

1671
826
845

1239
624
615

1902
942
960

1671
826
845

183,106
83,064
100,042

178,296
81,83496,462

183,106
83,064
100,042

183,106
83,064
100,042

183,106
83,064
100,042

183,106
83,064
100,042

115,32155,504
59,817

216,379
99,433116,946

183,106
83,064
100,042

98
23
75

42
10
32

76
17
59

87
18
69

57
14
43

31
4
27

58
12
46

119
27
92

73
17
56

0.54
0.28
0.75
0.37
0.20
0.68
0.001

0.24
0.12
0.33
0.37
0.19
0.72
0.003

0.42
0.20
0.59
0.35
0.17
0.70
0.003

0.48
0.22
0.69
0.31
0.16
0.61
,0.001

0.31
0.17
0.43
0.39
0.19
0.79
,0.01

0.17
0.05
0.27
0.18
0.06
0.51
0.001

0.50
0.22
0.77
0.28
0.13
0.59
,0.001

0.55
0.27
0.79
0.35
0.18
0.67
0.002

0.40
0.20
0.56
0.37
0.21
0.62
,0.001

IRRs,1 favor ClearGuard. 95% LCI, lower 95% conﬁdence interval; 95% UCI, upper 95% conﬁdence interval.

The study was approved by New England Independent Review
Board (IRB# 15–281), which also granted a patient informed consent
waiver. The informed consent waiver was important for conducting
the study in a pragmatic manner, adherence to the prescribed intervention, and broad inclusion.

Intervention Phase

After the run-in period, facilities entered a 13-month intervention
phase. During this phase, patients in the Tego+Curos group began
including Curos (and continued using Tego). Patients in the ClearGuard group converted from Tego to ClearGuard. Patients with a CVC
received the facility’s assigned intervention at their ﬁrst dialysis session after the study start date, and new patients with CVCs coming
Run-In Phase
Upon randomization, facilities entered into a 3-month run-in phase.
into the facility were added as appropriate throughout the study.
During this phase both study arms were treated according to facility
In the Tego+Curos group, Curos was replaced each session andstandard policy (including use of Tego). The purpose of this period was
Tego was replaced once per week according to existing facility prototo assess whether BSI rates were equivalent between study arms before
cols. In the ClearGuard group, ClearGuard caps were replaced each
institution of study interventions.
session.
Aside from CVC capping, all patients weretreated according to local standard of careand existing physician orders. This included
standard surveillance for potential BSI, which
adhered to the NHSN guidelines. All blood
cultures were sent to and processed by a single
clinical lab (DaVita Labs, Deland, FL). As isstandard policy, blood culture results were reported into the electronic health record in auFigure 4. Each patient’s at-risk time is dependent on when the patient began and tomated fashion, from which they wereabstracted for analysis.
ended CVC use during the study period.

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Outcomes and Analysis
The primary study outcome was blood culture positivity rate. This wascalculated by dividing the cumulative number of PBCs (as deﬁned
according to NHSN guidelines) by CVC time at-risk (Figure 4). To
avoid double-counting the same BSI, patients were censored using
the CDC’s NHSN-recommended 21-day rule: a PBC is counted only
if it occurred 21 days or more after a previously reported PBC in thesame patient.26 To account for biologic latency between catheter
seeding and clinical manifestation of BSI, at-risk time began on day
21 after ﬁrst receipt of study intervention and continued until end of
study, death, CVC removal, or loss to follow up; by extension, patientstreated with a CVC for ,21 days were excluded from analysis. In
addition, multiple exploratory analyses were conducted using DaVita
electronic records, which include microbiology, NHSN surveillance,and other records.
The IRRs and the corresponding 95% conﬁdence intervals for theﬁnal analysis were calculated using a Poisson regression model with alog link function and the natural logarithm of patient-days at risk as anoffset and adjusted for the facility cluster effect, where each matchedfacility pair was considered a cluster.

ACKNOWLEDGMENTS
We extend our sincere appreciation to the teammates in .2000
DaVita clinics who work every day to take care of patients and also toensure the extensive data collection on which our work is based. We
thank all of the DaVita Clinical Research teammates who contributed
to this work. We thank NAMSA (North American Science Associates
Inc.) for performing the statistical analysis.
An abstract of this study was published as a late-breaking clinical
trial in the National Kidney Foundation Spring Clinical Meetings,
Orlando, Florida, April 18–22, 2017.
Trial registration (www.clinicaltrials.gov): NCT02593149.

DISCLOSURESThis study was supported by Pursuit Vascular Inc. S.M.B. is an employee of
DaVita Clinical Research; D.B.V.W. and L.N. are employees of DaVita Inc.; L.E.
L., D.P.K., and R.J.Z. are employees of Pursuit Vascular Inc. and may havepatents, board membership, and/or stock ownership. Pursuit Vascular sponsored the study and thus paid DaVita Clinical Research, the clinical researchorganization of DaVita, for conducting the study. No additional ﬁnancial
relationships exist between DaVita and Pursuit Vascular.

REFERENCES
1. Nguyen DB, Shugart A, Lines C, Shah AB, Edwards J, Pollock D, et al.:National healthcare safety network (NHSN) dialysis event surveillance
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See related editorial, “Targeting Zero Infections in Dialysis: New Devices, Yes,
but also Guidelines, Checklists, and a Culture of Safety,” on pages 1083–1084.

Preventing Catheter-Related Bloodstream Infection

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