CLINICAL RESEARCH STUDY
Chlorhexidine Bathing to Reduce Central Venous Catheterassociated Bloodstream Infection: Impact and Sustainability
Marisa A. Montecalvo, MD,a,b Donna McKenna, MS,a,b Robert Yarrish, MD,c Lynda Mack, MSN,a George Maguire, MD,d
Janet Haas, DNSc,a,b Lawrence DeLorenzo, MD,d Norine Dellarocco, MSN,e Barbara Savatteri, RN,f Addie Rosenthal, MS,g
Anita Watson, RN,h Debra Spicehandler, MD,g Qiuhu Shi, PhD,i Paul Visintainer, PhD,j Gary P. Wormser, MD,b
Infection Prevention and Control Department, Westchester Medical Center, Valhalla, New York; bDivision of Infectious Diseases, Department of
Medicine, New York Medical College, Valhalla, New York; cDepartment of Medicine, Sound Shore Medical Center, New Rochelle, New York;
Pulmonary and Critical Care Medicine, Department of Medicine, New York Medical College, Valhalla, New York; eInfection Control, Sound Shore
Medical Center, New Rochelle, New York; fHudson Valley Hospital Center, Cortlandt Manor, New York; gMount Vernon Hospital, Mt Vernon, New
York; hPhelps Memorial Hospital Center, Sleepy Hollow, New York; iNew York Medical College School of Health Sciences and Practice, Valhalla,
New York; jBaystate Medical Center, Springfield, Mass.
BACKGROUND: Chlorhexidine bathing has been associated with reductions in healthcare-associated bloodstream
infection. To determine the impact and sustainability of the effect of chlorhexidine bathing on central venous
catheter-associated bloodstream infection, we performed a prospective, 3-phase, multiple-hospital study.
METHODS: In the medical intensive care unit and the respiratory care unit of a tertiary care hospital and the
medical-surgical intensive care units of 4 community hospitals, rates of central venous catheter-associated bloodstream infection were collected prospectively for each period. Pre-intervention (phase 1) patients were bathed with
soap and water or nonmedicated bathing cloths; active intervention (phase 2) patients were bathed with 2%
chlorhexidine gluconate cloths with the number of baths administered and skin tolerability assessed; post-intervention
(phase 3) chlorhexidine bathing was continued but without oversight by research personnel. Central venous catheterassociated bloodstream infection rates were compared over study periods using Poisson regression.
RESULTS: Compared with pre-intervention, during active intervention there were significantly fewer central venous
catheter-associated bloodstream infections (6.4/1000 central venous catheter days vs 2.6/1000 central venous catheter
days, relative risk, 0.42; 95% confidence interval, 0.25-0.68; P ⬍ .001), and this reduction was sustained during
post-intervention (2.9/1000 central venous catheter days; relative risk, 0.46; 95% confidence interval, 0.30-0.70;
P ⬍ .001). During the active intervention period, compliance with chlorhexidine bathing was 82%. Few adverse
events were observed.
CONCLUSION: In this multiple-hospital study, chlorhexidine bathing was associated with significant
reductions in central venous catheter-associated bloodstream infection, and these reductions were sustained
post-intervention when chlorhexidine bathing was unmonitored. Chlorhexidine bathing was well tolerated
and is a useful adjunct to reduce central venous catheter-associated bloodstream infection.
© 2012 Published by Elsevier Inc. • The American Journal of Medicine (2012) 125, 505-511
KEYWORDS: Central venous catheter-associated bloodstream infection; Chlorhexidine bathing; Healthcare-associated bloodstream infection.
Reduction of healthcare-associated infections is a top priority for hospitals. In intensive care units, infection is com-
mon and associated with significant morbidity and mortality.1 Healthcare-associated infections are often device-
Presented in part at: the Society for Health Care Epidemiology of
America 5th Decennial International Conference on Healthcare-Associated
Infections, 2010, Atlanta, Georgia.
Funding: New York State Department of Health Hospital-Acquired Infection Reporting Program. Interpretations of data do not necessarily represent
interpretation or policy of the New York State Department of Health. Chlorhexidine cloths were provided by Sage Products Inc, Cary, Ill.
Conflict of Interest: None.
Authorship: All authors had access to the data and played a role in
writing this manuscript.
Reprint requests should be addressed to: Marisa A. Montecalvo, MD,
Infection Prevention and Control, Macy Pavilion 2095, Westchester Medical Center, Valhalla, NY 10595.
E-mail address: firstname.lastname@example.org.
0002-9343/$ -see front matter © 2012 Published by Elsevier Inc.
The American Journal of Medicine, Vol 125, No 5, May 2012
associated and can be caused by antibiotic-resistant pathogens that
in Westchester County, New York. The study units were the
flourish in the hospital environment. Preventing healthcare-assomedical intensive care unit of the tertiary care hospital,
ciated infections requires rigorous infection control efforts that are
which houses oncology and critically ill medical patients
usually focused on the healthcare provider.2 A complementary
but does not include trauma/surgical patients; the respirainfection control measure is to reduce the number of patients
tory care unit of the tertiary care hospital, which houses
colonized with a hospital pathogen
medical and surgical patients rethrough decolonization strategies.
quiring ongoing mechanical ventiThis is known as “source control,” but
lation or respiratory care; and
its use has been limited by few availmedical-surgical intensive care
units of the 4 community hospi● This 3-phase (pre-intervention, interBathing patients with the antiseptals, each of which houses a varivention [chlorhexidine bathing], posttic chlorhexidine is a potential tool for
ety of critically ill medical and
intervention), multiple-hospital study
source control. The mechanism of ansurgical patients.
found a statistically significant reductibacterial action involves attachment
The study end point was hospition in central venous catheter-associof the positively charged chlorhexital-acquired central venous catheated bloodstream infection during chlordine to the negatively charged bacteter-associated bloodstream infechexidine bathing, and the reduction
rial cell causing leakage of cytoplasm,
tion rates. The inclusion criterion
was sustained during the post-intervenresulting in bactericidal or bacteriofor chlorhexidine bathing was adtion period.
static activity. Chlorhexidine reduces
mission to the study unit. Excluboth resident and transient skin flora
sion criteria were pregnancy,
● Chlorhexidine bathing was well tolewith a residual effect that lasts at least
breast feeding, chlorhexidine alrated.
lergy, and severely denuded skin.
The study was approved with a
Vernon et al
cleansing medical intensive care unit
waiver for written informed conful adjunctive measure for reducing cenpatients with 2% chlorhexidine-satusent by the New York Medical
tral venous catheter-associated bloodrated cloths resulted in significantly
College Committee for Protection
fewer colonies of vancomycin-resisof Human Subjects and by the intant enterococci on patients’ skin and
stitutional review board of each
significantly less contamination of the
environment and healthcare workers’ hands. The incidence of
Phase 1 (pre-intervention) started April 1, 2008, at all
acquisition of vancomycin-resistant enterococci was reduced by
hospitals and lasted for 6 to 9 months on each unit; the
60%.5 Subsequently, studies of chlorhexidine bathing in the same
different time intervals allowed units to transition to phase
2 separately. During phase 1, patients were bathed accordunit and in another medical intensive care unit found that the
ing to hospital protocol; nonmedicated bathing cloths were
period of chlorhexidine bathing was associated with significant
used at sites A, B, and E, and soap and water in a basin bath
reductions in primary bloodstream infections and central venous
were used at sites C, D, and F.
catheter-associated bloodstream infections. By using an alterna8
Phase 2 (active intervention) began immediately after
tive method to the chlorhexidine saturated cloths, Climo et al
evaluated the effect of adding 4% liquid chlorhexidine to paphase 1 and lasted for 8 months on each unit. During phase
tients’ bath water. In that multiple-hospital study, there were
2, bathing was performed with 2% chlorhexidine gluconate
significantly fewer vancomycin-resistant enterococcal bloodcloths (Sage Products Inc, Cary, Ill) provided to the hospital
stream infections and fewer patients acquired vancomycinat no charge. The bathing protocol was to use 1 package of
resistant enterococci and methicillin-resistant Staphylococcus
6 cloths with 1 cloth for each of the following anatomic
aureus during the period of chlorhexidine bathing.
areas: the neck/shoulders and chest, both arms and hands,
To extend our understanding of the efficacy of chlorhexiabdomen/groin/perineum, right leg/foot, left leg/foot, and
dine bathing, we performed a prospective, 3-phase, multiback and buttocks. If needed, more than 1 package was
ple-hospital study designed to evaluate the effect of chloused. The face was cleansed with nonmedicated cloths.
rhexidine bathing on central venous catheter-associated
During the week before chlorhexidine bathing began, all
bloodstream infection and the sustainability of any effect
nursing staff received in-service education on bathing prodetected. In addition, skin tolerability and frequency of
cedures, study requirements to record the chlorhexidine
bathing were assessed during the active intervention period.
baths administered on a research flow sheet, and how to
assess skin tolerability (at each shift) in consultation with
research personnel. Research personnel made rounds on all
MATERIALS AND METHODS
study units at least weekly.
Study Design, End Points, and Setting
Phase 3 (post-intervention) began immediately after
The study was a prospective, 3-phase study performed from
phase 2 and lasted for 12 months on each unit. During phase
April 1, 2008, to August 31, 2010. This study was per3 hospitals could continue chlorhexidine bathing, but the
formed at 1 tertiary care hospital and 4 community hospitals
product was no longer supplied by the study. All 6 units
Montecalvo et al
Study Unit Characteristics During the Pre-Intervention, Active Intervention, and Post-Intervention Periods
Average Length of Stay in Days*
Medical intensive care
Medical surgical intensive
Medical surgical intensive
Medical surgical intensive
Medical surgical intensive
*Derived from the number of patient days divided by the number of admissions.
†On the first day of the active intervention period, the unit moved from a 7-bed unit to an 11-bed unit.
chose to continue chlorhexidine bathing using the same
product and bathing protocol. Research personnel kept track
of whether chlorhexidine bathing was in use, but the baths
administered were no longer recorded on research forms.
Research personnel continued to be available for any questions regarding skin tolerability.
Throughout all phases of the study, the Infection Prevention and Control Department at each site had policies and
procedures in the intensive care unit that emphasized the
importance of insertion checklists9 to reduce central venous
catheter-associated bloodstream infection.
During the pre-intervention period of the study, site C
began using an antibiotic impregnated central venous catheter 5 months before chlorhexidine bathing began, and site
D began using a chlorhexidine-impregnated central venous
catheter dressing 3 months before chlorhexidine bathing
All positive blood cultures were reviewed by infection prevention and control staff at each site and classified as central
venous catheter-associated bloodstream infection and as
hospital-acquired using the National Healthcare Safety Network of the Centers for Disease Control and Prevention
definition.10 A central venous catheter-associated bloodstream infection was defined as a patient with a central
venous catheter in place with a recognized pathogen cultured from one or more blood cultures AND the organism
was not related to an infection at another site; or a common
skin organism was cultured from 2 or more blood cultures
drawn on separate occasions (within 2 days of each other)
AND at least 1 of the following signs or symptoms was
present: fever (⬎38°C), chills, or hypotension, AND the
signs and symptoms and positive blood cultures were not
due to infection at another site. Central venous catheterassociated bloodstream infection was defined as acquired on
the study unit if the signs and symptoms of infection were
not incubating at the time of admission and the positive
blood culture was drawn while the patient was housed on
the unit or within 48 hours of the time of discharge from the
unit. The denominator for the central venous catheter-associated bloodstream infection rates was 1000 central venous
catheter days. Days eligible for a bath included the day of
admission to the unit, the day of discharge from the unit,
and all days hospitalized on the unit.
The sample size estimate was derived from a known rate of
4 healthcare-associated bacteremias per 1000 patient days at
the tertiary care medical center during the year before the
study began. On the basis of published studies, it was
assumed that chlorhexidine bathing would result in a 50%
reduction of healthcare-associated bloodstream infection.6
To achieve a statistically significant reduction (P ⫽ .05) in
central venous catheter-associated bloodstream infection
with a power of 80%, the sample size estimate was 12,700
patient days each for the pre-intervention period and 12,700
patient days for the active intervention period.
Infection rates were modeled over the 3 study periods
using Poisson regression.11 In this approach, total infection
counts are adjusted for total central venous catheter days,
stratified by hospital and study period. Both hospital and
study period were modeled using indicator variables. Results are expressed as adjusted incidence rate ratios with
accompanying 95% confidence intervals (CIs). Pairwise
comparison of rates over study periods was conducted using
the Wald test with Bonferroni’s adjustment to the P value.
We conducted a subanalysis that excluded the 2 sites (C and
D) that had initiated parallel interventions that may have
influenced study results. The subanalyses were conducted as
described above. Analyses were conducted using Stata version 11.1 (StataCorp, College Station, Tex) and SAS version 9.1 (SAS Institute Inc, Cary, NC). A critical test level
of 5% was considered statistically significant, unless adjusted for multiple comparisons.
The study unit characteristics, number of beds, and average
length of stay during each period of the study are shown in
Table 1. The number of patient days and the number of
admissions for each study phase was 12,603 patient days,
1808 admissions for the pre-intervention period; 13,864
patient days, 1832 admissions for the active intervention
period; and 19,914 patient days and 2834 admissions for the
The American Journal of Medicine, Vol 125, No 5, May 2012
Table 2 Rates of Central Venous Catheter-associated Bloodstream Infection During the Pre-Intervention, Active Intervention, and
No. of Central
No. of Central
No. of Central
*Post-intervention all sites continued chlorhexidine bathing; sites E and F had periods of bathing without chlorhexidine of 4 and 5 months,
†Rate ⫽ number of central venous catheter-associated bloodstream infections per 1000 central venous catheter days.
‡The central venous catheter-associated bloodstream infection rate is adjusted for total central venous catheter days, stratified by hospital and study
days; relative risk [RR], 0.42, 95% CI, 0.25-0.68; P ⬍ .001)
(Table 2). This reduction was sustained during the postintervention period (2.9/1000 central venous catheter days;
RR, 0.46; 95% CI, 0.30-0.70; P ⬍ .001) (Figure 1). There
was little difference in the rates of central venous catheterassociated bloodstream infection between the active intervention period and the post-intervention period (P ⫽ .9).
During the lapse in chlorhexidine bath supply at sites E and
F during the post-intervention period, 1 site had 2 infections
(Table 2). These numbers were considered too small to
reassess the chlorhexidine effect. A subanalysis was performed excluding sites C and D, which had begun using
other products that may reduce central venous catheter-
Central venous catheter-associated bloodstream
infecon rate per 1000 central venous catheter days
post-intervention period. On the first day of the active intervention period, site A moved the intensive care unit from
a 7-bed unit to a new 11-bed unit. Exclusions from chlorhexidine bathing occurred for 2 patients during the active
intervention period, 1 due to pregnancy and 1 due to StevensJohnson syndrome. Chlorhexidine bathing was discontinued
in 3 patients because of skin rash and restarted in 2 of the 3
patients without adverse event; the third patient also had
thrombocytopenia that resolved with the discontinuation of
multiple medications and chlorhexidine.
During the active intervention period, chlorhexidine
baths were given on 12,196 (82%) of 14,942 days that
patients were eligible for a bath. A total of 18,357 chlorhexidine baths were given, indicating an average of 1.5
chlorhexidine baths daily. The reasons recorded for not
administering a chlorhexidine bath included the patient being admitted to or discharged from the unit that day (54% of
missed baths) or unknown (46% of missed baths). During
the post-intervention period, chlorhexidine baths were in
use by study units for 17,519 (88%) of 19,914 post-intervention study days. Two units, E and F, did not use chlorhexidine for bathing for 4 and 5 months, respectively, because of lapses in product supply at the beginning of the
post-intervention period when chlorhexidine baths were no
longer provided by the study.
Rates of central venous catheter-associated bloodstream
infection, unadjusted and adjusted for study center, are
shown in Table 2. Compared with the pre-intervention
period adjusted rate (6.4/1000 central venous catheter days),
there was a significant reduction in the rate of central venous catheter-associated bloodstream infection during the
active intervention period (2.6/1000 central venous catheter
Figure 1 Adjusted rates of central venous catheter-associated
bloodstream infection with limits of the 95% CI range for each
Montecalvo et al
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