Skin colonisation at the catheter exit site is strongly associated with catheter colonisation and catheter-related sepsis

Impact of daily octenidine skin washing versus nonwashing on antiseptic tolerance of coagulase-negative staphylococci in two neonatal intensive care units with different skin cleansing practices

Background

There is wide variation in practices regarding routine bathing/washing of babies in neonatal intensive care units (NICUs). Evidence is lacking as to the benefit of routine antiseptic washes for reducing infection. We aimed to compare the antiseptic tolerance of Coagulase Negative Staphylococci (CoNS) within two UK NICUs with very different approaches to skin washing.

Methods

We compared antiseptic susceptibility of CoNS isolated from skin swabs of neonates admitted to the Norfolk and Norwich University Hospital (NNUH) NICU in December 2017-March 2018 with those isolated in the Bradford Royal Infirmary (BRI) NICU in January-March 2020. The NNUH does not practise routine whole-body washing whereas BRI practises daily whole-body washing from post-menstrual age 27 weeks using Octenisan wash lotion (0.3% octenidine; 1 minute contact time before washing off with sterile water). A total of 78 CoNS isolates from BRI and 863 from the NNUH were tested for susceptibility against the antiseptics octenidine (OCT) and chlorhexidine (CHX).

Results

Isolates from the BRI with practice of routine washing did not show increased antiseptic tolerance to OCT or CHX. Isolates from the NNUH which does not practise routine whole-body washing and rarely uses octenidine, were comparatively less susceptible to both CHX and OCT antiseptics.

Conclusions

Daily whole-body skin washing with OCT does not appear to select for CoNS isolates that are antiseptic tolerant towards OCT and CHX. There remains considerable uncertainty about the impact of different antiseptic regimes on neonatal skin microbiota, the benefit of routine washing, and the development of antiseptic tolerance in the NICU.

2% chlorhexidine gluconate aqueous versus 2% chlorhexidine gluconate in 70% isopropyl alcohol for skin disinfection prior to percutaneous central venous catheterisation: the ARCTIC randomised controlled feasibility trial

OBJECTIVE

Catheter-related sepsis (CRS) is a major complication with significant morbidity and mortality. Evidence is lacking regarding the most appropriate antiseptic for skin disinfection before percutaneous central venous catheter (PCVC) insertion in preterm neonates. To inform the feasibility and design of a definitive randomised controlled trial (RCT) of two antiseptic formulations, we conducted the Antiseptic Randomised Controlled Trial for Insertion of Catheters (ARCTIC) feasibility study to assess catheter colonisation, sepsis, and skin morbidity.

DESIGN

Feasibility RCT.

SETTING

Two UK tertiary-level neonatal intensive care units.

PATIENTS

Preterm infants born <34 weeks' gestation scheduled to undergo PCVC insertion.

INTERVENTIONS

Skin disinfection with either 2% chlorhexidine gluconate (CHG)-aqueous or 2% CHG-70% isopropyl alcohol (IPA) before PCVC insertion and at removal.

PRIMARY OUTCOME

Proportion in the 2% CHG-70% IPA arm with a colonised catheter at removal.

MAIN FEASIBILITY OUTCOMES

Rates of: (1) CRS, catheter-associated sepsis (CAS), and CRS/CAS per 1,000 PCVC days; (2) recruitment and retention; (3) data completeness.

SAFETY OUTCOMES

Daily skin morbidity scores recorded from catheter insertion until 48 hours post-removal.

RESULTS

116 babies were randomised. Primary outcome incidence was 4.1% (95% confidence interval: 0.9% to 11.5%). Overall catheter colonisation rate was 5.2% (5/97); CRS 2.3/1000 catheter days; CAS 14.8/1000 catheter days. Recruitment, retention and data completeness were good. No major antiseptic-related skin injury was reported.

CONCLUSIONS

A definitive comparative efficacy trial is feasible, but the very low catheter colonisation rate would make a large-scale RCT challenging due to the very large sample size required. ARCTIC provides preliminary reassurance supporting potential safe use of 2% CHG-70% IPA and 2% CHG-aqueous in preterm neonates.

TRIAL REGISTRATION NUMBER

ISRCTN82571474.

Chlorhexidine gluconate usage is associated with antiseptic tolerance in staphylococci from the neonatal intensive care unit

Background

Intravascular catheters are essential for care in Neonatal Intensive Care Units (NICUs) but predispose infants to catheter-associated infections including late-onset sepsis, commonly caused by CoNS. Antiseptics are applied to prevent infection with chlorhexidine (CHG) and octenidine (OCT) the most common agents used.

Objectives

To investigate the association between antiseptic use and bacterial susceptibility.

Methods

CoNS isolates were collected from two NICUs with differing antiseptic regimens: Norwich, UK (using CHG) and Lubeck, Germany (using OCT). CoNS were isolated from different body sites of babies upon admission, and weekly thereafter. Antiseptic susceptibility testing was performed, and a selection underwent genome sequencing.

Results

A total of 1274 isolates were collected. UK isolates (n = 863) were significantly less susceptible than German isolates (n = 411) to both CHG (mean MIC: 20.1 mg/L versus 8.9 mg/L) and OCT (mean MIC: 2.3 mg/L versus 1.6 mg/L). UK isolates taken on admission were more susceptible to CHG than subsequent isolates. No cross-resistance between the agents was seen. Genome sequencing of 122 CoNS showed the most common species to be Staphylococcus epidermidis and Staphylococcus haemolyticus and phylogenetic analysis suggested antiseptic tolerance evolved multiple times in independent lineages. There was no evidence of dominant antiseptic tolerant clones and carriage of genes previously implicated in antimicrobial susceptibility (qac, smr, norA/B), did not correlate with CHG or OCT susceptibility.

Conclusions

Long-term CHG use may select for CHG and OCT tolerance in CoNS. This highlights the different potential for separate antiseptic regimens to select for resistance development. This could be an important factor in developing future infection control policies.

Antimicrobial-impregnated central venous catheters for preventing neonatal bloodstream infection: the PREVAIL RCT

BACKGROUND

Clinical trials show that antimicrobial-impregnated central venous catheters reduce catheter-related bloodstream infection in adults and children receiving intensive care, but there is insufficient evidence for use in newborn babies.

OBJECTIVES

The objectives were (1) to determine clinical effectiveness by conducting a randomised controlled trial comparing antimicrobial-impregnated peripherally inserted central venous catheters with standard peripherally inserted central venous catheters for reducing bloodstream or cerebrospinal fluid infections (referred to as bloodstream infections); (2) to conduct an economic evaluation of the costs, cost-effectiveness and value of conducting additional research; and (3) to conduct a generalisability analysis of trial findings to neonatal care in the NHS.

DESIGN

Three separate studies were undertaken, each addressing one of the three objectives. (1) This was a multicentre, open-label, pragmatic randomised controlled trial; (2) an analysis was undertaken of hospital care costs, lifetime cost-effectiveness and value of information from an NHS perspective; and (3) this was a retrospective cohort study of bloodstream infection rates in neonatal units in England.

SETTING

The randomised controlled trial was conducted in 18 neonatal intensive care units in England.

PARTICIPANTS

Participants were babies who required a peripherally inserted central venous catheter (of 1 French gauge in size).

INTERVENTIONS

The interventions were an antimicrobial-impregnated peripherally inserted central venous catheter (coated with rifampicin-miconazole) or a standard peripherally inserted central venous catheter, allocated randomly (1 : 1) using web randomisation.

MAIN OUTCOME MEASURE

Study 1 - time to first bloodstream infection, sampled between 24 hours after randomisation and 48 hours after peripherally inserted central venous catheter removal. Study 2 - cost-effectiveness of the antimicrobial-impregnated peripherally inserted central venous catheter compared with the standard peripherally inserted central venous catheters. Study 3 - risk-adjusted bloodstream rates in the trial compared with those in neonatal units in England. For study 3, the data used were as follows: (1) case report forms and linked death registrations; (2) case report forms and linked death registrations linked to administrative health records with 6-month follow-up; and (3) neonatal health records linked to infection surveillance data.

RESULTS

Study 1, clinical effectiveness - 861 babies were randomised (antimicrobial-impregnated peripherally inserted central venous catheter, n = 430; standard peripherally inserted central venous catheter, n = 431). Bloodstream infections occurred in 46 babies (10.7%) randomised to antimicrobial-impregnated peripherally inserted central venous catheters and in 44 (10.2%) babies randomised to standard peripherally inserted central venous catheters. No difference in time to bloodstream infection was detected (hazard ratio 1.11, 95% confidence interval 0.73 to 1.67; p = 0.63). Secondary outcomes of rifampicin resistance in positive blood/cerebrospinal fluid cultures, mortality, clinical outcomes at neonatal unit discharge and time to peripherally inserted central venous catheter removal were similar in both groups. Rifampicin resistance in positive peripherally inserted central venous catheter tip cultures was higher in the antimicrobial-impregnated peripherally inserted central venous catheter group (relative risk 3.51, 95% confidence interval 1.16 to 10.57; p = 0.02) than in the standard peripherally inserted central venous catheter group. Adverse events were similar in both groups. Study 2, economic evaluation - the mean cost of babies' hospital care was £83,473. Antimicrobial-impregnated peripherally inserted central venous catheters were not cost-effective. Given the increased price, compared with standard peripherally inserted central venous catheters, the minimum reduction in risk of bloodstream infection for antimicrobial-impregnated peripherally inserted central venous catheters to be cost-effective was 3% and 15% for babies born at 23-27 and 28-32 weeks' gestation, respectively. Study 3, generalisability analysis - risk-adjusted bloodstream infection rates per 1000 peripherally inserted central venous catheter days were similar among babies in the trial and in all neonatal units. Of all bloodstream infections in babies receiving intensive or high-dependency care in neonatal units, 46% occurred during peripherally inserted central venous catheter days.

LIMITATIONS

The trial was open label as antimicrobial-impregnated and standard peripherally inserted central venous catheters are different colours. There was insufficient power to determine differences in rifampicin resistance.

CONCLUSIONS

No evidence of benefit or harm was found of peripherally inserted central venous catheters impregnated with rifampicin-miconazole during neonatal care. Interventions with small effects on bloodstream infections could be cost-effective over a child's life course. Findings were generalisable to neonatal units in England. Future research should focus on other types of antimicrobial impregnation of peripherally inserted central venous catheters and alternative approaches for preventing bloodstream infections in neonatal care.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN81931394.

FUNDING

This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 57. See the NIHR Journals Library website for further project information.

Skin colonization at peripheral intravenous catheter insertion sites increases the risk of catheter colonization and infection

BACKGROUND

Peripheral intravenous catheters (PIVCs) break the skin barrier, and preinsertion antiseptic disinfection and sterile dressings are used to reduce risk of catheter-related bloodstream infection (CRBSI). In this study, the impact of PIVC skin site colonization on tip colonization and the development of CRBSI was investigated.

METHODS

A total of 137 patients' PIVC skin site swabs and paired PIVC tips were collected at catheter removal, cultured, and bacterial species and clonality were identified.

RESULTS

Of 137 patients, 45 (33%) had colonized skin sites and/or PIVC tips. Of 16 patients with paired colonization of both the skin site and PIVC tips, 11 (69%) were colonized with the same bacterial species. Of these, 77% were clonally related, including 1 identical clone of Pseudomonas aeruginosa in a patient with systemic infection and the same organism identified in blood culture.

CONCLUSIONS

The results demonstrate that opportunistic pathogen colonization at the skin site poses a significant risk for PIVC colonization and CRBSI. Further research is needed to improve current preinsertion antiseptic disinfection of PIVC skin site and the sterile insertion procedure to potentially reduce PIVC colonization and infection risk.

Safety and efficacy of 2% chlorhexidine gluconate aqueous versus 2% chlorhexidine gluconate in 70% isopropyl alcohol for skin disinfection prior to percutaneous central venous catheter insertion in preterm neonates: the ARCTIC randomised-controlled feasibility trial protocol

INTRODUCTION

Catheter-related sepsis is one of the most dangerous complications of neonatal intensive care and is associated with significant morbidity and mortality. Use of catheter-care 'bundles' has reduced the incidence of catheter-related sepsis, although individual components have not been well studied. Better evidence is needed to guide selection of the most appropriate antiseptic solution for skin disinfection in preterm neonates. This study will inform the feasibility and design of the first randomised controlled trial to examine the safety and efficacy of alcohol-based versus aqueous-based chlorhexidine antiseptic formulations for skin disinfection prior to percutaneous central venous catheterisation in preterm neonates. The antiseptics to be compared are 2% chlorhexidine gluconate (CHG) aqueous and 2% CHG in 70% isopropyl alcohol.

METHODS AND ANALYSIS

The Antiseptic Randomised Controlled Trial for Insertion of Catheters (ARCTIC) is a two-centre randomised-controlled feasibility trial. At least 100 preterm infants born at <34 weeks' gestation and due to undergo percutaneous insertion of a central venous catheter will be randomly allocated to receive prior skin disinfection with one of the two antiseptic solutions. Outcomes include: i) recruitment and retention rates; ii) completeness of data collection; iii) numbers of enrolled infants meeting case definitions for definite catheter-related sepsis, catheter-associated sepsis and catheter colonisation and iv) safety outcomes of skin morbidity scores recorded daily from catheter insertion until 48 hours post removal. The key feasibility metrics will be reported as proportions with 95% CIs. Estimated prevalence of catheter colonisation will allow calculation of sample size for the large-scale trial. The data will inform whether it will be feasible to progress to a large-scale trial.

ETHICS AND DISSEMINATION

ARCTIC has been approved by the National Health Service Health Research Authority National Research Ethics Service Committee East of England (Cambridge South) (IRAS ID 163868), was adopted onto the National Institute of Health Research Clinical Research Network portfolio (CPMS ID 19899) and is registered with an International Standard Randomised Control Trials Number (ISRCTN: 82571474; Pre-results) and European Clinical Trials Database number 2015-000874-36. Dissemination plans include presentations at scientific conferences, scientific publications and sharing of the findings with parents via the support of Bliss baby charity.

TRIAL REGISTRATION NUMBER

ISRCTN82571474; Pre-results.

Evaluation of Skin Colonisation And Placement of vascular access device Exit sites (ESCAPE Study)

Background

Skin microorganisms may contribute to the development of vascular access device (VAD) infections. Baseline skin microorganism type and quantity vary between body sites, yet there is little evidence to inform choice of VAD site selection.

Objective

To compare microorganisms present at different body sites used for VAD insertions and understand the effect of transparent dressings on skin microflora.

Methods

The ESCAPE observational study consisted of three phases: (1) skin swabs of four sites (mid-neck, base neck, chest, upper arm) from 48 hospital patients; (2) skin swabs of five body sites (mid-neck, base neck, chest, upper arm, lower arm) from 10 healthy volunteers; and (3) paired skin swabs (n = 72) under and outside of transparent dressings from 36 hospital patients (16 mid/base neck, 10 chest, upper arm). Specimens were cultured for 72 h, species identified and colony-forming units (CFU) counted. Ordinal logistic regression compared CFU categories between variables of interest.

Results

The chest and upper arm were significantly associated with fewer microorganisms compared to neck or forearm (odds ratio [OR] = 0.40, 95% confidence interval [CI] = 0.25-0.65, P < 0.05). CFU levels under transparent dressings were not significantly different from outside (OR = 0.57, 95% CI = 0.22-1.45). Staphylococci were predominant at all sites. Other significant (P < 0.05) predictors of higher CFU count included prolonged hospitalisation and medical/surgical patient status.

Discussion

Skin microorganism load was significantly lower at the upper arm or chest, compared to the mid- or base neck. This may impact VAD site selection and subsequent infection risk.

Variation in infection prevention practices for peripherally inserted central venous catheters: A survey of neonatal units in England and Wales

Background

There is uncertainty about the variation in infection prevention practices for central venous catheters (CVC) in neonatal units (NNUs) and how practices relate to national guidance.

Aim

To evaluate evidence supporting infection prevention practices for CVCs recommended in national guidelines and to compare with reported practices for peripherally inserted central catheters (PICC), a type of CVC widely used in NNUs.

Design

We searched national guidelines for neonates and children to identify infection prevention practices for CVCs and conducted an overview of studies to determine the quality of evidence underpinning recommendations. We surveyed 134 NNUs in England and Wales to ascertain reported practice.

Results

We found low quality evidence supporting CVC care bundles and use of 2% alcoholic chlorhexidine to decontaminate catheter ports and skin before insertion. Moderate quality evidence supported recommendations against routinely replacing CVCs and against chlorhexidine-impregnated dressings. 90% (44/49) of NICUs and 40% (34/85) of LNUs responded. 66% (48/73) of NNUs reported using CVC care bundles for insertion; 62% (45/73) used bundles for maintenance. 63% (32/51) of those using bundles reported monitoring adherence. 85% (61/72) of NNUs did not routinely replace PICCs and 89% (63/71) did not use chlorhexidine-impregnated dressings. Antiseptic use varied with alcoholic 2% chlorhexidine used for skin preparation in 33% (23/71) of NNUs and for catheter ports in 52% (37/71).

Conclusions

Lack of consistency across NNUs in antiseptic use and low rates of reported CVC care bundle use may reflect the low quality of evidence of the effectiveness and safety of these interventions in NNUs. Clinical trials are needed to quantify benefits and harms of infection prevention practices in NNUs.

The Microbiota of the Extremely Preterm Infant

Colonization of the extremely preterm infant's gastrointestinal tract and skin begins in utero and is influenced by a variety of factors, the most important including gestational age and environmental exposures. The composition of the intestinal and skin microbiota influences the developing innate and adaptive immune responses with short-term and long-term consequences including altered risks for developing necrotizing enterocolitis, sepsis, and a wide variety of microbe-related diseases of children and adults. Alteration of the composition of the microbiota to decrease disease risk is particularly appealing for this ultra-high-risk cohort that is brand new from an evolutionary standpoint.

Efficacy of two antiseptic regimens on skin colonization of insertion sites for two different catheter types: a randomized, clinical trial

Purpose

Catheter-related bloodstream infections affect patients in surgical and intensive care settings worldwide, causing complications, aggravation of existing symptoms and increased length of stay. The trial aimed at comparing two registered skin antiseptics with respect to their residual and therefore infection-preventing effects.

Methods

In a parallel, monocentric, prospective, triple-blind, randomized trial the difference in bacterial recolonization of catheter skin sites in central venous (CVC) and epidural catheters (EC) was investigated by comparing two alcoholic-based skin disinfectants. Patients receiving planned surgeries or intensive care were eligible for the trial. Those in the trial group received skin disinfection with the additive octenidine dihydrochloride (OCT) (n = 51), those in the control group were treated with benzalkonium chloride as additive (BAC) (n = 59) prior to catheter insertion. Randomization was carried out by assigning patients to groups week-wise. Endpoints of the investigation were skin colonization of the catheter site counted in colony forming units per swab at three time points: (1) prior to catheter insertion, on untreated skin; (2) directly after catheter insertion, prior to sterile coverage; (3) 48 h after catheter insertion. The hypothesis was tested by a Wilcoxon test with a two-sided alpha = 5 %.

Results

From second to third swab, recolonization of the catheter-surrounding skin was significantly lower in the trial group for both sorts of catheters: delta 2–3 OCT group: 0.72 (95 % CI: 0.42; 1.02); delta 2–3 BAC group: 1.97 (95 % CI: 1.45; 2.50); p < 0.001. None of the patients enrolled developed a catheter-related blood stream infection (CRBSI) during follow-up.

Conclusions

Previous studies have shown that skin colonization is strongly associated with the occurrence of CRBSI. This randomized controlled trial supports the observations made in previous trials that octenidine dihydrochloride in disinfectants is more effective than agents containing other additives with regard to skin recolonization surrounding CVC and EC insertion sites. Therefore, it is likely to also reduce the risk of CRBSI in these patient groups. The trial was approved by the North Rhine Medical Association in July 2014 (application-no.: 2014222).

Molecular Comparison of Bacterial Communities on Peripheral Intravenous Catheters and Matched Skin Swabs

Skin bacteria at peripheral intravenous catheter (PIVC) insertion sites pose a serious risk of microbial migration and subsequent colonisation of PIVCs, and the development of catheter related bloodstream infections (CRBSIs). Common skin bacteria are often associated with CRBSIs, therefore the bacterial communities at PIVC skin sites are likely to have major implications for PIVC colonisation. This study aimed to determine the bacterial community structures on skin at PIVC insertion sites and to compare the diversity with associated PIVCs. A total of 10 PIVC skin site swabs and matching PIVC tips were collected by a research nurse from 10 hospitalised medical/surgical patients at catheter removal. All swabs and PIVCs underwent traditional culture and high-throughput sequencing. The bacterial communities on PIVC skin swabs and matching PIVCs were diverse and significantly associated (correlation coefficient = 0.7, p<0.001). Methylobacterium spp. was the dominant genus in all PIVC tip samples, but not so for skin swabs. Sixty-one percent of all reads from the PIVC tips and 36% of all reads from the skin swabs belonged to this genus. Staphylococcus spp., (26%), Pseudomonas spp., (10%) and Acinetobacter spp. (10%) were detected from skin swabs but not from PIVC tips. Most skin associated bacteria commonly associated with CRBSIs were observed on skin sites, but not on PIVCs. Diverse bacterial communities were observed at skin sites despite skin decolonization at PIVC insertion. The positive association of skin and PIVC tip communities provides further evidence that skin is a major source of PIVC colonisation via bacterial migration but microbes present may be different to those traditionally identified via culture methods. The results provide new insights into the colonisation of catheters and potential pathogenesis of bacteria associated with CRBSI, and may assist in developing new strategies designed to reduce the risk of CRBSI.