Review articles © The Intensive Care Society 2009

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IntroductionHospital-acquired infection is a serious problem in the ICU,and is a major cause of further morbidity and eventualmortality of critically ill patients. It also contributes toprolonged stay in the ICU, with its associated costimplications.

The susceptibility of patients in the ICU, combined with therisk factors associated with the invasive treatments andmonitoring that they may be receiving, and the ICUenvironment itself, contribute to the increased risk of infectionin this patient group. Breaches of the mucosal defences of theinnate immune system by endotracheal intubation andmechanical ventilation, urinary catheters, the use of peripheralvenous and arterial catheters, as well as central venouscatheters, can all provide ready access for pathogens in analready immunocompromised patient. Infection in critically illpatients can be further complicated by the fact that clinicalsigns may be absent or hidden by signs of co-existing disease.1

Hospital-acquired infections are defined as infectionsdeveloping more than 48 hours after admission.2 In animmunocompromised host, these can be caused by pathogenicorganisms, commensal flora and environmental bacteria andfungi, leading to atypical infections by opportunisticmicroorganisms.

It is estimated that 78% of critically ill patients have someform of central venous catheter (CVC).3 Infection of CVCs has

an associated mortality of between 10 and 35%.4.5 The absolutenumber of CVC-related infections is rising annually due to theirincreasing use, although the incidence per catheter day hasactually decreased.6 Additionally, each CVC-related infection ispredicted to cost the healthcare provider €3,124 in Europe7 andup to $30,000 in America,4 due partly to a significantly longerstay in ICU.8 This review will therefore concentrate on causes ofcentral venous catheter-associated infection, and mechanisms toprevent these infections from occurring.

Infection associated with central venouscatheter useInfection associated with central venous catheter use is thoughtto be a consequence of catheter colonisation. This occurs eitherduring insertion,9 or during the subsequent care of thecatheter.10 It is important to distinguish between colonisation,which may affect up to 25% of catheters inserted5 and whichhas no serious clinical effects, and catheter-related bloodstreaminfection (CRBSI), otherwise defined as sepsis due to aninfected CVC. This is thought to affect 5% of catheterisedpatients.5,11

CRBSI is defined as the presence of more than 15 colonyforming units (CFU) per catheter tip, with at least oneconcurrent positive blood culture from peripheral bloodcontaining the same bacterial species with the same sensitivity.Significant colonisation is defined as the presence of ≥15 CFU

Catheter-related bloodstream infection inthe intensive care unitRL Curtis

Catheter-related bloodstream infection (CRBSI) is a significant cause of morbidity and mortality in the intensive care unit,

contributing to prolonged stay with the associated cost and resource implications. Various mechanisms of infection have

been suggested, and consequently, numerous interventions to reduce the burden of infection have been proposed, the

efficacy of most of which remains controversial. The practice of routine catheter change and preferential use of the

subclavian vein insertion site are both associated with an increased risk of mechanical complications, which may

outweigh any potential benefit. Additionally, the use of silver- and antiseptic-impregnated catheters, of questionable

benefit in the ICU patient population, is also argued to be unjustified in terms of efficacy and cost.

A small scale study in a London university district general hospital ICU found that while infection rates were low, the

majority of infections were caused by Staphylococcus epidermidis and thus were probably a result of contamination

either from the patient’s commensal flora or acquired by contamination from healthcare workers. In accordance with

published findings, this suggests that preventing contamination will decrease infection rates. Strict aseptic technique and

the use of sterile fields during insertion are most likely the main contributors in reducing rates of infection. This together

with education of staff across disciplines and adherence to local guidelines are likely to be the mainstays of reducing

CRBSI in the ICU.

Keywords: central venous catheter; intensive care unit; CRBSI; silver-impregnated catheter; antiseptic-impregnated catheter; insertion site

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in the absence of sepsis.5 Catheter tips are commonly assessedfor the presence of bacteria in UK hospitals using the ‘RollPlate’ method when there is clinical suspicion of a CRBSI. Thismethod is a semi-quantitative analysis of the external cathetersurface and is assumed to correlate with the number ofmicroorganisms present in the catheter wound site. A positiveresult is representative of a local infection of the wound site,which is significant as septicaemia related to catheter usage isthought to start as a local wound infection.12

Causes of CRBSIThe catheter insertion site itself provides the most direct routeof entry for the pathogen and this is the most common cause ofCRBSI.5 These infections are caused mainly by gram-positivebacteria, in particular Staphylococcus aureus and coagulase-negative staphylococci such as Staphylococcus epidermidis,which is the most common.10 However, infections can becaused by a wide range of microorganisms includingEnterococci, Candida spp,13 Acinetobacter spp, Pseudomonas spp,and Klebsiella spp. It is likely that specific pathogens varydepending on different ICUs, and the individual colonisationprofile of the patient. In long-term catheters, the hub of thecatheter is the main area for colonisation and portal ofinfection12 and it is suggested that increasing length ofcatheterisation is linked with a greater risk of developing acatheter-related infection.14,15

As most cases of CRBSI are caused by skin commensals, it isproposed that these organisms are able to migrate from the skinat the insertion site, and colonise the external catheter surface,eventually causing a catheter-related bloodstream infection.10

This colonisation can take less than 24 hours followinginsertion.10 Micro-organisms colonise indwelling CVCs byforming a biofilm over the catheter surface.16 This change instate is triggered by phenotypic changes linked to theupregulation of specific genes enhancing survival. Bacteria inbiofilms are more resistant to antimicrobials and host defencemechanisms17 and are more resistant to shear forces. This is animportant attribute for survival on catheters within large bloodvessels. It is also proposed that bacterial motility is enhanced ina biofilm model, aiding colonisation and dissemination.18

Treatment of CRBSIOnce sepsis is suspected on clinical grounds, removal of thecatheter is often sufficient for recovery. If sepsis is more severe,the patient is given intravenous broad spectrum antibioticsuntil laboratory results confirm the organism responsible forthe infection. Antibiotic sensitivity and resistance profiling isundertaken to allow a specific treatment regimen to be tailoredto the individual patient.

Costs associated with CRBSICritically ill patients are at particular risk of catheter-relatedinfection. Indeed it is proposed that 42.3% of sepsis cases inEngland are related to the use of central lines.19

A recent American study investigating cost implication ofCRBSI in ICU patients found that these patients weremechanically ventilated for a proportionately longer time andthat this was associated with multiple ICU admissions. Almost

Pathogen Number of positive % of total cultures (n=27) positive cultures

Staphylococcus epidermidis 13 48

Coliforms 8 30

MRSA 1 3.7

Acinetobacter spp 1 3.7

Enterococcus faecalis 1 3.7

Enterococcus spp 1 3.7

Micrococcus spp 1 3.7

Pseudomonas aeruginosa 1 3.7

Table 1 Bacterial isolates from catheter tips over a 12-monthperiod.

Staphylococcusepidermidis

Coliforms

Other

Figure 1 Identity of the bacterial isolates from colonised CVC lines.

50% of these costs were related to extended stay in the ICUand the increase in associated nursing costs.8

CRBSI in a university district general hospitalIt is probable that the causative organisms of CRBSI andantibiotic sensitivity and resistance profiles vary between units,and that this is likely to affect the severity of outcome. Anestimation of the rate of infection and identification of thecausative organisms may give a clue as to the route of entryand pathogenesis of the infection, and this in turn may point tomethods in which CRBSI can be reduced.

The rate of catheter tip colonisation in septic patients in aLondon university district general hospital ICU was

investigated over a 12-month period. During this time, 326patients were admitted to the ICU; it was assumed that allpatients were catheterised. When sepsis was suspected onclinical grounds, in cases where no other cause could be found,lines were removed and the tips sent for microbiologicalanalysis using the semi-quantitative method. Although bloodcultures were simultaneously analysed to confirm the presenceof a CRBSI, this data was unavailable for this study andconsequently the rate of colonisation actually giving rise to aCRBSI is undetermined.

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other studies where they made up a considerably smallerproportion.6,8,18 However, the sample size here is very small,and it is impossible to formally compare the results obtained inlarger scale studies. Coliforms are commonly found in thegastrointestinal system and their presence may implycontamination in some form from the gut. The ICU studiedadmits a large number of post-operative surgical patientsreceiving care following emergency gastrointestinal surgery, soit is unsurprising that a proportion of these patients havecolonisation of lines associated with coliform organisms.

The sensitivity and resistance profiles of S. epidermis isolatescultured from catheter tips were investigated. Results indicateda range of antibiotic sensitivities and resistance patterns, aswould be expected for a hospital-acquired infection with S.epidermidis (Figure 2). All isolates were sensitive to vancomycinand teicoplanin. Ninety-two per cent of samples were resistantto gentamicin, erythromycin, penicillin and meticillin, as wouldbe expected for gram-positive coagulase-negative staphylococci;85% of isolates were resistant to fusidic acid.

In summary, this small-scale study found that the rate ofcolonisation of lines in the unit was low, and that coagulase-negative staphylococci made up the majority of the isolates,followed by coliforms. This data supports the hypothesis thatthe major source of contamination is via the skin. Whether thisoccurs via the patient’s own commensal flora, or contaminationfrom healthcare staff is unknown. Thorough skin asepsis priorto insertion, and during the period of catheterisation may playa role in reducing this contamination.

This study had a number of limitations. Positive tip cultureresults were not correlated to results from peripheral bloodcultures.21 The duration of catheterisation and the co-morbidities of the patients, which could be measured using theAPACHE score,22 are unknown. The length of catheterisationprior to the patient developing sepsis is unknown, as is thefunction of the catheter. This is important, as it may haveincreased the infection risk and been an indicator of theseverity of illness. It is possible that these patients had long-term catheters. Additionally, it is likely that a number of lineswere not sent for microbiological investigation, and weresimply removed and disposed of. Further investigation ofadditional data could be examined to investigate anycorrelation between length of catheterisation and infectionrates in this patient population, as well as confirming the truerate of CRBSI.

Prevention of CRBSIAs a result of the serious implications of CRBSI, there havebeen a number of studies investigating different ways toprevent infection, or reduce its occurrence. Among these, havebeen investigations into the use of sterile fields and aseptictechnique during insertion, the use of antiseptic- andantimicrobial-impregnated catheters to decrease colonisationand subsequent infection, the significance of routine changingof catheters and whether the insertion site impacts on the riskof developing an infection. Additionally, it is proposed thateducating healthcare staff impacts on decreasing infection rates.There have been a number of initiatives and guidelinesproposed to decrease the levels of CRBSI nationally.3,19

Review articles

0

25

50

75

100

% r

esis

tant

isol

ates

Gentamycin

Erythromycin

Penicillin

Meticillin

Fusid

ic acid

Vancomycin

Teico

planin

Antibiotic

Figure 2 Antibiotic resistance of S. epidermidis isolates.

The catheters were standard ‘Quad-Lumen’ (Arrow-Howes™), with no antiseptic or antimicrobial coating.Catheters were inserted by trained ICU specialist doctors,either in the ICU itself or in the operating theatre. Strict aseptictechnique was maintained both during the procedure and whilehandling the catheter in situ. Catheters inserted in generalwards, and in the accident and emergency department wereremoved and re-inserted in the ICU as described above.

All positive catheter tip culture results over the 12 monthperiod were analysed for causative pathogen and resistanceprofile. One hundred and nineteen catheter tips from 83patients with clinical signs of sepsis were cultured over thetime period. Of these 119 catheter samples, 27 were positivefor significant colonisation. There was a variety of bacterialisolates cultured from the CVCs (Table 1). The rates ofcolonisation with non-commensal organisms are low,suggesting that a specific strain of bacteria in the unit is notendemic. The rate of significant colonisation of catheter tips inseptic patients over the 12 month period was 8%, which isrelatively low, and the true rate of CRBSI is possibly even lowerassuming that some samples were colonised but not infected.

The most common pathogens isolated were Staphylococcusepidermidis (13/27), and coliforms (8/27) (Figure 1). Theremainder is made up of a variety of opportunisticmicroorganisms, including Acinetobacter spp and Pseudomonasaeruginosa, both common causes of hospital-acquired infection.

The level of MRSA is reassuringly low, in contrast to manyother units.20

Staphylococcus epidermidis accounts for almost 50% of allCVC-associated infections at this hospital. This suggests thatinfection occurs as a result of contamination from the skin,either during insertion or while the catheter is in situ. The factthat S. epidermidis, which causes an opportunistic infection, isthe most common cause of infection, is not altogethersurprising; this organism has been found to be thepredominant cause of infection caused by standard CVCs inother studies within similar populations.6,8,10

Coliforms made up 30% of isolates. This is in contrast to

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Aseptic technique and sterile fieldsThere is evidence that the single most effective intervention indecreasing the incidence of CVC-related infection is related toaseptic technique during insertion and scrupulous infectioncontrol measures.3 Maximal barrier precautions duringinsertion of the CVC minimises subsequent infection rates16,23

and is more important in reducing the risk of infection thanthe sterility of the room where the procedure is carried out.24

Based on the evidence, it is strongly recommended thatmedical staff wash hands prior to any contact withintravascular devices. Additionally, maximal sterile techniqueand infection control measures, including the use of sterilegloves and surgical gowns, as well as the use of masks andsterile drapes, must be employed.25

Cutaneous antisepsis is important in reducing skincolonisation and the consequent catheter hub contamination.In one study, 2% aqueous chlorhexidine was the most effectiveantiseptic agent in preventing CVC-related infection, comparedwith alcohol and povidone-iodine.26

Once the catheter is in situ, antiseptic wiping of the catheterhub prior to accessing the catheter system is recommended.25 Ithas been proposed that CVC-related infections may be theresult of colonised hubs.24 Frequent manipulation of thecatheter hub is linked with an increased risk of developing acatheter-related infection27 and therefore, appropriatedisinfection prior to manipulation may play an important rolein reducing infection rates. In long-term catheters, the hubs arefrequently accessed for various reasons and this constantcontamination risk may be the source of the catheter-relatedinfection.24 The NHS ‘care bundle’,19 aiming to reduce theincidence of CRBSI in UK hospitals, places great emphasis onstrict hygiene, both during insertion and related to ongoingcare. In addition, it is proposed that adherence to guidelinesand monitoring their use can significantly decrease infectionrates.28

Routine catheter changesIt has been proposed that the risk of CRBSI increases withincreasing duration of catheterisation. However, randomisedcontrolled trials show that routine replacement of cathetersdoes not decrease infection rates,14,29 and may be linked withincreased risk of mechanical complications, as well asunnecessary use of staff and financial resources.30 In addition,routine changes of catheters carry a risk of morbidity andmortality in critically ill patients.31 A telephone survey of ICUsin the UK found that 52% of those surveyed routinely changedCVCs after a mean time period of 6.5 days.30 Of these, 59%could give no reason for this change,30 and indeed there is alack of evidence in the literature supporting the theory thatrisk of sepsis is linked to longer duration of catheterisation.Routine change of a CVC over a guide wire at the same site isassociated with an increased risk of infection compared torelocating the catheter at a new site, although it carries areduced risk of mechanical complications.31 In light of this,routine change of catheters in the absence of clinical signs ofinfection, may be an unnecessary procedure associated withunacceptable and unjustifiable risk.

Silver- and antiseptic-impregnated cathetersColonisation is hypothesised to be the first step in causinginfection. Therefore, inhibiting or reducing this colonisationstage by impregnating catheters with antimicrobial substancesmay lead to a decrease in infection rates. However, whetherthis has an impact on reducing infection rates in vivo iscontroversial. There are numerous studies with conflictingresults.

A number of in vitro and in vivo studies have shown thatimpregnating catheters with antibiotics and antiseptic agents,such as silver derivatives, decreases colonisation ratescompared to standard catheters.15,18,32,33 However, these studiesdid not investigate the rate of CVC-related infection, thusmaking it difficult to draw firm clinical conclusions from thedata. These findings are supported by a multicentre,randomised double-blind controlled trial, where it was foundthat CVC colonisation rates could be reduced by usingcatheters impregnated with chlorhexidine and sulfadiazine.18

However, this reduction in colonisation rates did not impact onthe incidence of CRBSI, which raises questions of whetherthere is a true progression between colonisation and infection,and if so, what the pathogenesis is.

Conversely, other studies have demonstrated thatimpregnating catheters with antiseptic agents does not decreaserates of colonisation, and therefore does not impact oninfection rates.6,10,34 A randomised study investigating theimpact of chlorhexidine and silver sulfadiazine-impregnatedcatheters found no difference between these catheters and thecontrol catheter group. In this study, catheter colonisation, andCRBSI were both investigated. Catheters under study wereimpregnated on the external surface only,10 which raises furtherquestions about the validity of comparing the differentproducts. It is possible that impregnation on both surfaceswould be more effective. The study raised the possibility thathub contamination may be the main source of bacterialcontamination in patients with long-term catheters.10

One recent study investigated the use of a new generation ofsilver-impregnated catheters compared with standard multi-lumen catheters. These catheters release silver ions from bothinternal and external surfaces continuously during their use,potentially decreasing initial colonisation and subsequentbiofilm formation. The end-point for this prospective,randomised study was catheter tip colonisation, assuming thatthis correlates to CRBSI.21 There was no statistically significantdifference in colonisation rates nor infection rates between thesilver-impregnated catheter tested and standard catheters.Additionally, there was no difference between the species ofmicro-organism colonising the catheter.6

It has been shown that impregnation of catheters withantimicrobials is more effective at reducing colonisation andinfection rates compared with antiseptic-impregnated catheters.This may in part be because again, the two types of cathetersdiffered in their impregnation. The antimicrobial catheter wascoated on both internal and external surfaces, whereas theantiseptic catheter was coated only on the external surface.35

This may have affected the result, and as the pathogenesis ofinfection is as yet unclear, it is difficult to truly compare the

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two groups. There was no control group in this study, and thebaseline rate of infection with standard CVCs was unclear. It ishypothesised also that routine use of antimicrobial-coatedcatheters may contribute to development of resistant strains,36

compounding the difficulties associated with treating CVC-related infection, although this is disputed.24,35

Although these results may be specific to the type ofcatheter being tested, and may be inconclusive due to thelimitations of the studies, they highlight both the excess costassociated with using impregnated catheters in the light ofminimal discernible benefit, and again raise the issues ofwhether colonisation and infection are progressive.

Meta-analysis of three large-scale studies looking into theuse of antimicrobial- and antiseptic-impregnated cathetersconcluded that, although they may reduce incidence of CVC-related infection in units with a high baseline rate, the findingsmay not be applicable to units where infection rates are low.37

This finding is supported by a meta-analysis of 12 randomisedcontrolled trials,38 which compared the efficacy of CVCsimpregnated with chlorhexidine and silver sulfasalazine, inreducing infection rates compared with standard catheters. Thestudy concluded that impregnated catheters reduce theincidence of colonisation and catheter-related infection only inpatients at high risk of infection.

It appears that a conclusion is yet to be reached on theefficacy of antiseptic- and antimicrobial-impregnated cathetersin preventing infection in clinical practice. In light of thecurrent lack of evidence and increased associated costs, as wellas low baseline infection rates in UK ICUs, the routine use ofimpregnated catheters is not justified. NHS guidelinesrecommend the use of antimicrobial-impregnated cathetersonly if the duration of catheterisation will be prolonged, and ifthe patient is at increased risk of a CRBSI.19 Despite this, manyhospitals do not use antimicrobial-coated catheters at all. Asthese impregnated catheters decrease colonisation rates andhave antiseptic actions in vitro, it is likely that future modelsmay be more effective in preventing bacteraemia, provided thatcatheter colonisation is the main factor leading to infection.

Importance of insertion siteInfection risks associated with catheter insertion into thesubclavian, internal jugular and femoral veins, have been thesubject of a number of prospective studies39-42 and extensivelyreviewed.3,25 It is widely believed that the femoral route isassociated with higher rates of infection41 and there are studiesto support this.39,40 It has been demonstrated that CVCinsertion into the subclavian vein is associated with the lowestrate of infection3 and this approach is recommended inAmerican hospitals.25 A prospective, observational studydemonstrated that the safest central venous access, in terms ofavoiding infection, was the subclavian vein, followed by thejugular vein, and lastly the femoral vein.42 Unfortunately,mechanical complications occur most often duringcatheterisation of the subclavian and internal jugular veins.The higher rates of infection associated with use of the internaljugular vein compared to the subclavian vein may be due todifficulty in maintaining occlusive dressings at the site, theproximity of the area to the mouth and oropharnx, and a high

density of skin commensals.42 It is suggested that thereportedly increased risk of infection at the femoral site is dueto the high density of skin commensal flora in the groin.43

Despite these results, a recent non-randomised, prospectivestudy has demonstrated that within the ICU population, CRBSIrates, as defined by clinical signs and a positive culture resultusing the semi-quantitative method, are lower than in thegeneral hospital population and that the three sites are safe interms of infection risk.41 This, however, is dependent upon themost suitable site being chosen, and insertion performed bytrained senior doctors with aseptic technique. Consequent careand monitoring must be carried out by trained ICU nurses, inaccordance with strict infection control protocols. Additionally,there was no significant difference between organisms culturedfrom infected catheters from the different sites.41 It is likely thatit is the careful insertion and subsequent care that reduces thelevels of infections to such low rates. Whether the results ofthis study are relevant for every ICU is a different matter, andmay be dependent upon resources, staffing levels and training.Although this appears to contradict the results of previousstudies, it is supported by another recent study, which foundthat although there was a difference in the rate of minorinfections at the three sites, there was no statistically significantdifference in rates of CVC-related bloodstream infections.40

The siting of CVCs is a controversial issue. It is importantthat risk of infection is carefully balanced with the risk ofmechanical complications, which may be less at a site deemeda higher theoretical risk for infection.25 A pneumothorax in acritically ill ICU patient caused during insertion of CVC intothe subclavian or internal jugular vein may be life-threatening,whereas this complication can be avoided by catheterising thefemoral vein. Although some studies have shown no differencebetween the three sites,40,41 it is possible that this lack ofdifference was due to increased hygiene and surveillanceduring the study. Although the findings here are inconclusive,it does appear to support the theory that strict aseptictechnique, insertion by trained senior doctors and care bytrained nursing staff may be the most important means ofdecreasing CVC-related infection.

DiscussionCatheter-related bloodstream infection is a complication ofcentral venous catheter use. The issue is particularly grave inthe ICU population. Infection results in higher levels ofmorbidity and mortality in this patient group, coupled withgreater costs in terms of care and increased duration of hospitalstay. In an already over-stretched healthcare system such as theNational Health Service, a reduction in patient morbidity andmortality coupled with a reduction in costs would be a hugebenefit.

Many strategies have been proposed to decrease the rate ofinfection in catheterised patients, however, it appears thatmany of these measures impact on decreasing infection rateswhere the baseline level is high.37 In the intensive care setting,where infection rates should be low due to maximal sterilebarrier precautions during insertion and subsequent sterilecare, the benefits may be minimal and not justify the excessassociated costs.

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Infections are thought to arise via contamination fromcommensal skin flora, and may be introduced during insertionor subsequent care.44 In this study, S. epidermidis, a skincommensal was the main cause of significant cathetercolonisation. Pathogens colonising the catheter itself arethought to predispose to infection in susceptible patients.Therefore, many of the strategies proposed to reduce infectionrates are targeted at either reducing the numbers of skin floraor decreasing colonisation levels. Sterile barrier precautionsand skin asepsis reduce contamination from commensalorganisms, and it is widely believed that routine change ofcatheters decreases colonisation levels, a practice whichhowever appears unjustified based on current evidence.30

Whether the location of the catheter impacts on CRBSI rates iscontroversial, but the risk of complications from a CVCinserted via the subclavian route in a critically ill patient maybe more severe than that of a slightly increased rate of infectionassociated with the femoral route. The use of cathetersimpregnated with antiseptic or antimicrobial substances mayreduce levels of significant colonisation. Although there is alack of evidence to support the role of these products inreducing CRBSI currently, this is an important area for futurestudy. Provided that there is a definite link betweencolonisation and infection, impregnation of catheters oninternal and external surfaces and hubs may reduce bacterialgrowth, but should not become an alternative to scrupulousaseptic insertion technique and aftercare.

Identifying the cause of CRBSI may be an important step infinding measures to prevent infection. It may be that this variesbetween units. Infection rates are likely to be linked to facilitiesin each ICU, availability and education of staff, the role of themulti-disciplinary team and access to resources, and not justthe catheter type used, or the site of the central line.

In conclusion, maximal sterility during insertion withsuitable sterile barrier precautions and scrupulous sterile after-care of the wound and catheter hub can have a major impacton reducing the level of CVC-related infection. Although this ismaintained in ICUs, there may be room for improvement,dependent on staffing levels, adequate training and educationof medical and nursing staff, and provision of suitableequipment for insertion and subsequent care. Further trainingand education of all staff involved in insertion and subsequenthandling of CVCs, as well as monitoring the use of guidelinesmay have a positive impact on further reducing infection rates.Future work could investigate the current UK rates and causesof CVC-related infection specific to ICUs. The logistics ofimproving and standardising CVC-related care is an excitingarea, with potentially huge benefits for patients, which couldbe extended outside the ICU and into general ward-basedpatient care.

Although implementing change may be expensive in theshort-term, in the long-term it will almost certainly be cost-saving and will impact on patient morbidity. Until cathetersimpregnated with antiseptics or antimicrobials are shown to beeffective in reducing infection, or other measures to reduce oreven inhibit infection are introduced, basic hygiene and sterileprecautions are especially important in this era of antibioticresistance. As they were 100 years ago, simple hygiene and

cleanliness may be the main weapons in fighting infection,both now and in the future.

AcknowledgementThe author would like to thank Dr Jim Stephenson, Epsomand St Helier University Hospitals NHS Trust.

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Review articles

Roxana Curtis 4th year Medical Student, St George’s Hospital,

University of London

m0500401@sgul.ac.uk

This is an abridged version of the prize-winning medical student

essay, awarded by the ICS Research Committee in 2008