Guidelines for the Prevention of Intravascular Catheter-Related Infections: Recommendations Relevant to Interventional Radiology for Venous Catheter Placement and Maintenance

Introduction

In the United States, 80,000 catheter-related blood stream infection (CRBSIs) occur in intensive care units each year (1), and a total of 250,000 cases of CRBSIs have been estimated to occur annually, if entire hospitals are assessed (2). In the ICU, these infections independently increase hospital costs and length of stay (3–6), but have not generally been shown to independently increase mortality.

The second edition of the Centers for Disease Control (CDC) Guidelines for the Prevention of Intravascular Catheter-Related Infections was published on August 9, 2002 in the MMWR Reports and Recommendations series (7), and replaced the original guideline, published in 1996. The goal was to provide evidence-based recommendations for preventing catheter-related infections. Selected recommendations from the 2002 guideline relevant to interventional radiology were excerpted as an SIR guideline, published in JVIR in 2003 (8, 9).

Major areas of emphasis in the 2002 CDC Guidelines included 1) educating and training healthcare providers who insert and maintain catheters; 2) using maximal sterile barrier precautions during central venous catheter insertion; 3) using a 2% chlorhexidine preparation for skin antisepsis; 4) avoiding routine replacement of central venous catheters as a strategy to prevention of infection; and 5) using antiseptic/antibiotic impregnated short-term central venous catheters and chlorhexidine impregnated sponge dressings if the rate of infection is high despite adherence to other strategies (i.e. education and training, maximal sterile barrier precautions and 2% chlorhexidine for skin antisepsis).

Unfortunately, implementation of evidence-based CRBSI preventive practices in U.S. hospitals has been suboptimal (4, 10). In a national survey conducted in March 2005 of over 700 U.S. hospitals, approximately one quarter of U.S. hospitals indicated that either maximal sterile barrier precautions during central line insertion or chlorhexidine gluconate as site disinfectant, two practices widely recommended in the 2002 guidelines, were not being used routinely (11). Approximately 15% of U.S. hospitals reported routinely changing CVCs to prevent infection despite evidence that this practice should no longer be used (4, 11).

The 2002 CDC guideline has now been revised and updated. The new document, published in 2011 (12, 13), was prepared by a working group comprising members from professional organizations representing the disciplines of critical care medicine, infectious diseases, healthcare infection control, surgery, anesthesiology, interventional radiology, pulmonary medicine, pediatric medicine, and nursing. The working group was led by the Society of Critical Care Medicine, in collaboration with the Infectious Disease Society of America, Society for Healthcare Epidemiology of America, Surgical Infection Society, American College of Chest Physicians, American Thoracic Society, American Society of Critical Care Anesthesiologists, Association for Professionals in Infection Control and Epidemiology, Infusion Nurses Society, Oncology Nursing Society, American Society for Parenteral and Enteral Nutrition, the Society of Interventional Radiology, American Academy of Pediatrics, Pediatric Infectious Diseases Society, and the Healthcare Infection Control Practices Advisory Committee of the CDC.

The 83-page electronic version of the 2011 CDC guideline is available online without charge (http://www.cdc.gov/hicpac/pdf/guidelines/bsi-guidelines-2011.pdf). Major areas of emphasis in the 2011 guideline include 1) educating and training healthcare personnel who insert and maintain catheters; 2) using maximal sterile barrier precautions during central venous catheter insertion; 3) using a > 0.5% chlorhexidine skin preparation with alcohol for antisepsis; 4) avoiding routine replacement of central venous catheters as a strategy to prevent infection; and 5) using antiseptic/antibiotic impregnated short-term central venous catheters and chlorhexidine impregnated sponge dressings if the rate of infection is not decreasing despite adherence to other strategies (i.e., education and training, maximal sterile barrier precautions, and >0.5% chlorhexidine preparations with alcohol for skin antisepsis).

The CDC guideline is lengthy and includes recommendations regarding peripheral venous catheters, hand hygiene, umbilical catheters, peripheral arterial catheters and replacement of administration sets and needleless intravascular catheter systems. These topics are not reviewed here. Portions of the new guideline are of particular interest to interventional radiologists, particularly those dealing with central venous catheters (CVCs), peripherally inserted central catheters (PICCs) and hemodialysis catheters. This revised SIR guideline contains selected recommendations from the 2011 CDC guideline, presented verbatim, along with selected supporting data, background information, and references.

Definitions

Catheter-related bloodstream infection (CRBSI): a clinical definition, used when diagnosing and treating patients, which requires specific laboratory testing to identify more thoroughly the catheter as the source of the bloodstream infection. It is often problematic to precisely establish if a bloodstream infection is a CRBSI due to the clinical needs of the patient (the catheter is not always removed), limited availability of microbiologic methods (many laboratories do not use quantitative blood cultures or differential time to positivity), and procedural compliance by direct care personnel (labeling must be accurate).

Central line–associated bloodstream infection (CLABSI): term used by CDC’s National Healthcare Safety Network. A CLABSI is a primary bloodstream infection in a patient who had a central line within the 48-hour period before the development of the bloodstream infection, and is not related to an infection at another site. However, since some bloodstream infections are secondary to other sources (other than the central line) that may not be easily recognized (e.g., pancreatitis, mucositis), the CLABSI surveillance definition may overestimate the true incidence of CRBSI.

Microbiology

The most commonly reported causative pathogens remain coagulase-negative staphylococci, Staphylococcus aureus, enterococci, and Candida species (14). Gram-negative bacilli accounted for 19% and 21% of CLABSIs reported to CDC (15) and the Surveillance and Control of Pathogens of Epidemiological Importance (SCOPE) database, respectively (14).

For all common pathogens causing CLABSIs, antimicrobial resistance is a problem, particularly in ICUs. Although methicillin-resistant Staphylococcus aureus (MRSA) now account for more than 50% of all Staphylococcus aureus isolates obtained in ICUs, the incidence of MRSA CLABSIs has decreased in recent years, perhaps as a result of prevention efforts (16). For gram-negative rods, antimicrobial resistance to third generation cephalosporins among Klebsiella pneumoniae and E. coli has increased significantly as has imipenem and ceftazidine resistance among Pseudomonas aeruginosa (15). Candida species are increasingly noted to be fluconazole resistant.

Pathogenesis

There are four recognized routes for contamination of catheters: 1) migration of skin organisms at the insertion site into the cutaneous catheter tract and along the surface of the catheter with colonization of the catheter tip (the most common route of infection for short-term catheters) (17–19); 2) direct contamination of the catheter or catheter hub by contact with hands or contaminated fluids or devices (20, 21); 3) hematogenous seeding from another focus of infection (less common) (22); and 4) infusate contamination (rare) (23).

Important pathogenic determinants of CRBSI are 1) characteristics of the device material; 2) host factors, protein adhesions, such as fibrin and fibronectin, that form a sheath around the catheter (24); and 3) the intrinsic virulence factors of the infecting organism, including the extracellular polymeric substance (EPS) produced by the adherent organisms (25).

Due to fibrin sheath formation, silastic catheters are associated with higher risk of catheter infections than polyurethane catheters (24). On the other hand, biofilm formation by C. albicans occurs more readily on silicone elastomer catheter surfaces than on polyurethane catheters (26). Modification of the biomaterial surface properties has been shown to influence the ability of C. albicans to form biofilm (27). Some catheter materials have surface irregularities that enhance the microbial adherence of certain species (e.g., S. epidermidis and C. albicans) (26, 27). Catheters made of these materials are particularly vulnerable to microbial colonization and subsequent infection. Additionally, certain catheter materials are more thrombogenic than others, a characteristic that might also predispose to catheter colonization and infection (28, 29). This association has led to emphasis on preventing catheter-related thrombus as an additional mechanism for reducing CRBSI (30, 31).

Host factors are also important in the pathogenesis of CRBSI, as they affect the adherence properties of a given microorganism. For example, S. aureus can adhere to host proteins (e.g., fibrinogen, fibronectin) commonly present on catheters by expressing clumping factors that bind to the protein adhesins (24, 29, 32, 33). Microbial adherence is also enhanced through the production, by microbial organisms such as coagulase negative staphylococci (34, 35), S. aureus (36), Pseudomonas aeruginosa (37), and Candida species (38), of an EPS that consists mostly of an exopolysaccharide that forms a microbial biofilm layer (25, 39). This biofilm matrix is enriched by divalent metallic cations, such as calcium, magnesium and iron, enabling microbial organisms to embed themselves (40–42). These biofilms potentiate the pathogenicity of various microbes by allowing them to withstand host defense mechanisms (e.g., acting as a barrier to engulfment and killing by polymorphonuclear leukocytes) or by making them less susceptible to antimicrobial agents (e.g., forming a matrix that binds antimicrobials before their contact with the organism cell wall or providing for a population of metabolically quiescent, antimicrobial tolerant "persister" cells) (35, 43, 44). In the presence of dextrose-containing fluids, some Candida species produce slime similar to that of their bacterial counterparts, potentially explaining the increased proportion of BSIs caused by fungal pathogens among patients receiving parenteral nutrition fluids (45).

Classification of Recommendations

The 2011 CDC guideline contains a Summary of Recommendations with 99 specific recommendations. Each is categorized as Category IA (strongly recommended for implementation and strongly supported by well-designed experimental, clinical, or epidemiologic studies), Category IB (strongly recommended for implementation and supported by some experimental, clinical, or epidemiologic studies and a strong theoretical rationale; or an accepted practice (e.g., aseptic technique) supported by limited evidence), Category IC (Required by state or federal regulations, rules, or standards), Category II (suggested for implementation and supported by suggestive clinical or epidemiologic studies or a theoretical rationale), or Unresolved issue (represents an unresolved issue for which evidence is insufficient or no consensus regarding efficacy exists). The recommendations most relevant to the practice of interventional radiology are given below, with supporting information and references (the organization and numbering used here are different from those used in the CDC guideline).

General recommendations

1. Periodically assess knowledge of and adherence to guidelines for all personnel involved in the insertion and maintenance of intravascular catheters (46–54). Category IA

2. Designate only trained personnel who demonstrate competence for the insertion and maintenance of peripheral and central intravascular catheters (53–61). Category IA

3. Do not administer systemic antimicrobial prophylaxis routinely before insertion or during use of an intravascular catheter to prevent catheter colonization or CRBSI (62). Category IB

4. Do not routinely use anticoagulant therapy to reduce the risk of catheter-related infection in general patient populations (63). Category II

Catheter and site selection

1. Use a midline catheter or peripherally inserted central catheter (PICC), instead of a short peripheral catheter, when the duration of IV therapy will likely exceed six days. Category II

2. Use a fistula or graft in patients with chronic renal failure instead of a CVC for permanent access for dialysis (64). Category 1A

3. Use a CVC with the minimum number of ports or lumens essential for the management of the patient (65–68). Category IB

4. No recommendation can be made regarding the use of a designated lumen for parenteral nutrition. Unresolved issue

5. Promptly remove any intravascular catheter that is no longer essential (69–72). Category IA

6. Weigh the risks and benefits of placing a central venous device at a recommended site to reduce infectious complications against the risk for mechanical complications (e.g., pneumothorax, subclavian artery puncture, subclavian vein laceration, subclavian vein stenosis, hemothorax, thrombosis, air embolism, and catheter misplacement) (17, 73–88). Category IA

7. Avoid using the femoral vein for central venous access in adult patients (73, 85, 86, 89). Category 1A

8. Use a subclavian site, rather than a jugular or a femoral site, in adult patients to minimize infection risk for nontunneled CVC placement (85–87). Category IB

9. No recommendation can be made for a preferred site of insertion to minimize infection risk for a tunneled CVC. Unresolved issue

10. Avoid the subclavian site in hemodialysis patients and patients with advanced kidney disease, to avoid subclavian vein stenosis (88, 90–93). Category IA

The site at which a catheter is placed influences the subsequent risk for catheter-related infection and phlebitis. The influence of site on the risk for catheter infections is related in part to the risk for thrombophlebitis and in part on the density of local skin flora.

The density of skin flora at the catheter insertion site is a major risk factor for CRBSI. No single trial has satisfactorily compared infection rates for catheters placed in jugular, subclavian, and femoral veins. In retrospective observational studies, catheters inserted into an internal jugular vein have usually been associated with higher risk for colonization and/or CRBSI than those inserted into a subclavian (17, 73–82). Similar findings were noted in neonates in a single retrospective study (94).

Femoral catheters have been demonstrated to have high colonization rates compared with subclavian and internal jugular sites when used in adults and, in some studies, higher rates of CLABSIs (75, 80–82, 85, 86, 95). Femoral catheters are also associated with a higher risk for deep venous thrombosis than are internal jugular or subclavian catheters (83–85, 88, 96). One study found that the risk of infection associated with catheters placed in the femoral vein is accentuated in obese patients (73). In contrast to adults, studies in pediatric patients have demonstrated that femoral catheters have a low incidence of mechanical complications and might have an equivalent infection rate to that of non-femoral catheters (97–100). Thus, in adult patients, a subclavian site is preferred for infection control purposes, although other factors (e.g., the potential for mechanical complications, risk for subclavian vein stenosis, and operator skill) should be considered when deciding where to place the catheter.

Catheters should be inserted at as great a distance as possible from open wounds. In one study, catheters inserted close to open burn wounds (i.e., when the wound overlapped the 25 cm² area surrounding the catheter insertion site) were 1.79 times more likely to be colonized and 5.12 times more likely to be associated with bacteremia than catheters inserted farther from the wounds (101).

Antimicrobial/antiseptic impregnated catheters and cuffs

1. Use a chlorhexidine/silver sulfadiazine or minocycline/rifampin -impregnated CVC in patients whose catheter is expected to remain in place > 5 days if, after successful implementation of a comprehensive strategy to reduce rates of CLABSI, the CLABSI rate is not decreasing. The comprehensive strategy should include at least the following three components: educating persons who insert and maintain catheters, use of maximal sterile barrier precautions, and a > 0.5% chlorhexidine preparation with alcohol for skin antisepsis during CVC insertion (102–108). Category IA

Certain catheters that are coated or impregnated with antimicrobial or antiseptic agents can decrease the risk for CRBSI and could potentially decrease hospital costs associated with treating CRBSIs, despite the higher prices of antimicrobial or antiseptic impregnated catheters (108).

Nearly all of the studies involving antimicrobial/antiseptic-impregnated catheters have been conducted using triple-lumen, uncuffed catheters in adult patients whose catheters remained in place <30 days. These catheters have been approved by FDA for use in patients weighing >3 kg. Two non-randomized studies in pediatric ICU patients suggest that these catheters might reduce the risk of catheter-associated infection (107, 109). No antiseptic or antimicrobial impregnated catheters currently are available for use in infants weighing <3kg.

Two meta-analyses of catheters coated with chlorhexidine/silver sulfadiazine on the external luminal surface only (first-generation catheters) demonstrated that these catheters reduced the risk for CRBSI compared with standard non-coated catheters (1, 110). The duration of catheter placement in one study ranged from 5.1 to 11.2 days (111). A second-generation catheter is now available with chlorhexidine coating the internal surface, extending into the extension set and hubs, while the external luminal surface is coated with chlorhexidine and silver sulfadiazine. The external surface has three times the amount of chlorhexidine and extended release of the surface bound antiseptics compared to the first generation catheters. All three prospective, randomized studies of second-generation catheters demonstrated a significant reduction in catheter colonization, but they were underpowered to show a difference in CRBSI (103–105). Prolonged anti-infective activity provides improved efficacy in preventing infections (112). Although rare, anaphylaxis with the use of these chlorhexidine/silver sulfadiazine catheters has been observed (113–117).

In a multicenter randomized trial, CVCs impregnated on both the external and internal surfaces with minocycline/rifampin were associated with lower rates of CRBSI when compared with the first generation chlorhexidine/ silver sulfadiazine impregnated catheters (102). The beneficial effect began after day 6 of catheterization. Silicone minocycline/rifampin impregnated CVCs with an average dwell time of over 60 days have been shown to be effective in reducing CRBSI (106). No minocycline/rifampin-resistant organisms were reported in these studies. Two trials demonstrated that use of these catheters significantly reduced CRBSI compared with uncoated catheters (106, 108). No comparative studies have been published using the second-generation chlorhexidine/silver sulfadiazine catheter. Several prospective clinical studies have shown that the risk for development of resistance is low (118, 119). No resistance to minocycline or rifampin related to the use of the catheter has been documented in the clinical setting.

A combination platinum/silver impregnated catheter (i.e, a silver iontophoretic catheter) is available for use in the United States. Several prospective, randomized studies have been published comparing these catheters to uncoated catheters (120–123). One study showed a reduction in the incidence of catheter colonization and CRBSI (122), but the other studies found no difference in catheter colonization or CRBSI between the impregnated catheter and a non-impregnated catheter (74, 120, 121).

Barrier precautions

1. Use maximal sterile barrier precautions, including the use of a cap, mask, sterile gown, sterile gloves, and a sterile full body drape, for the insertion of CVCs, PICCs, or guidewire exchange (53, 124–126). Category IB

2. Use new sterile gloves before handling the new catheter when guidewire exchanges are performed. Category II

3. Wear either clean or sterile gloves when changing the dressing on intravascular catheters. Category IC

4. When adherence to aseptic technique cannot be ensured (i.e catheters inserted during a medical emergency), replace the catheter as soon as possible, i.e, within 48 hours (17, 28, 126–128). Category IB

Maximum sterile barrier (MSB) precautions are defined as wearing a sterile gown, sterile gloves, and cap and using a sterile full body drape during CVC placement. Maximal sterile barrier precautions during insertion of CVC were compared with sterile gloves and a small drape in a randomized controlled trial (124). The MSB group had fewer episodes of both catheter colonization (RR = .32, 95% CI, 0.10–0.96, P = .04) and CR-BSI (RR = .16, 95% CI, 0.02–1.30, P = .06). In addition, in the group where MSB precautions were used, infections occurred much later and contained gram negative, rather than gram positive, organisms. A study of pulmonary artery catheters also secondarily demonstrated that use of MSB precautions lowered risk of infection (17). Another study evaluated an educational program directed at improving infection control practices, especially MSB precautions (53). In this study, MSB precautions use increased and CRBSI decreased. A small trial demonstrated a reduced risk of skin colonization at the insertion site when MSB precautions were used [OR 3.40, 95%CI 1.32 to 3.67] (125).

Skin preparation

1. Prepare clean skin with a > 0.5% chlorhexidine preparation with alcohol before central venous catheter and peripheral arterial catheter insertion and during dressing changes. If there is a contraindication to chlorhexidine, tincture of iodine, an iodophor, or 70% alcohol can be used as alternatives (129, 130). Category IA

2. No comparison has been made between using chlorhexidine preparations with alcohol and povidone-iodine in alcohol to prepare clean skin. Unresolved issue.

3. Antiseptics should be allowed to dry according to the manufacturer’s recommendation prior to placing the catheter (129, 130). Category IB

Two well-designed studies evaluating the chlorhexidine-containing cutaneous antiseptic regimen in comparison with either povidone iodine or alcohol for the care of an intravascular catheter insertion site have shown lower rates of catheter colonization or CRBSI associated with the chlorhexidine preparation (129, 130). (A comparison of chlorhexidine gluconate alcohol to povidone iodine alcohol has not been done.) When 0.5% tincture of chlorhexidine was compared with 10% povidone iodine, no differences were seen in central venous catheter (CVC) colonization or in CRBSI (131). In a three-armed study (2% aqueous chlorhexidine gluconate vs. 10% povidone-iodine vs. 70% alcohol), 2% aqueous chlorhexidine gluconate tended to decrease CRBSI compared with 10% povidone iodine or 70% alcohol (129). A meta-analysis of 4,143 catheters suggested that chlorhexidine preparation reduced the risk of catheter related infection by 49% (95% CI .28 to .88) relative to povidone iodine (132). An economic decision analysis based on available evidence suggested that the use of chlorhexidine, rather than povidone iodine, for CVC care would result in a 1.6% decrease in the incidence of CRBSI, a 0.23% decrease in the incidence of death, and a savings of $113 per catheter used (133). While chlorhexidine has become a standard antiseptic for skin preparation for the insertion of both central and peripheral venous catheters, 5% povidone iodine solution in 70% ethanol was associated with a substantial reduction of CVC-related colonization and infection compared with 10% aqueous povidone iodine (134).

Dressings

1. Use either sterile gauze or a sterile, transparent, semipermeable dressing to cover the catheter site (135–138). Category IA

2. If the patient is diaphoretic or if the site is bleeding or oozing, use a gauze dressing until this is resolved (135–138). Category II

3. Do not use topical antibiotic ointment or creams on insertion sites, except for dialysis catheters, because of their potential to promote fungal infections and antimicrobial resistance (139, 140). Category IB

4. Do not submerge the catheter or catheter site in water. Showering should be permitted if precautions can be taken to reduce the likelihood of introducing organisms into the catheter (e.g., if the catheter and connecting device are protected with an impermeable cover during the shower) (141–143). Category IB

5. Replace dressings used on short-term CVC sites every 2 days for gauze dressings. Category II

6. Replace dressings used on short-term CVC sites at least every 7 days for transparent dressings, except in those pediatric patients in whom the risk for dislodging the catheter may outweigh the benefit of changing the dressing (138, 144). Category IB

7. Replace transparent dressings used on tunneled or implanted CVC sites no more often than once per week (unless the dressing is soiled or loose), until the insertion site has healed. Category II

8. No recommendation can be made regarding the necessity for any dressing on well-healed exit sites of long-term cuffed and tunneled CVCs. Unresolved issue

12. Use a chlorhexidine-impregnated sponge dressing for temporary short-term catheters in patients older than 2 months of age if the CLABSI rate is not decreasing despite adherence to basic prevention measures, including education and training, appropriate use of chlorhexidine for skin antisepsis, and MSB (REFS). Category 1B

13. No recommendation is made for other types of chlorhexidine dressings. Unresolved issue

A meta-analysis has assessed studies that compared the risk for CRBSIs using transparent dressings versus using gauze dressings (145). The risk for CRBSIs did not differ between the groups. The choice of dressing can be a matter of preference. If blood is oozing from the catheter insertion site, a gauze dressing is preferred. Another systematic review of randomized controlled trials comparing gauze and tape to transparent dressings found no significant differences between dressing types in CRBSIs, catheter tip colonization, or skin colonization (146).

Chlorhexidine impregnated dressings have been used to reduce the risk of CRBSI. In the largest multicenter randomized controlled trial published to date comparing chlorhexidine impregnated sponge dressings vs standard dressings in ICU patients, rates of CRBSIs were reduced even when background rates of infection were low. In this study, 1636 patients (3778 catheters, 28 931 catheter-days) were evaluated. The chlorhexidine-impregnated sponge dressings decreased the rates of CRBSIs (10/1953 [0.5%], 0.6 per 1000 catheter-days vs 19/1825 [1.1%], 1.4 per 1000 catheter-days; hazard ratio [HR], 0.39 [95% confidence interval {CI}, 0.17–0.93]; P = .03) and CRBSIs (6/1953 catheters, 0.40 per 1000 catheter-days vs 17/1825 catheters, 1.3 per 1000 catheter-days; HR, 0.24 [95% CI, 0.09–0.65]) [148]. A randomized controlled study of polyurethane or a chlorhexidine impregnated sponge dressing in 140 children showed no statistical difference in BSIs; however, the chlorhexidine group had lower rates of CVC colonization [153]. In 601 cancer patients receiving chemotherapy, the incidence of CRBSI was reduced in patients receiving the chlorhexidine impregnated sponge dressing compared to standard dressings (p=0.016, relative risk 0.54; confidence interval 0.31–0.94) [159]. A meta-analysis that included eight randomized controlled trials demonstrated that chlorhexidine impregnated sponge dressings are associated with a reduction of vascular and epidural catheter exit site colonization but no significant reduction in CRBSI (2.2% versus 3.8%, OR 0.58, 95% CI: 0.29–1.14, P = 0.11) [152].

Although data regarding the use of a chlorhexidine impregnated sponge dressing in children are limited, one randomized, controlled study involving 705 neonates reported a substantial decrease in colonized catheters in infants in the chlorhexidine impregnated sponge dressing group compared with the group that had standard dressings (15% versus 24%; RR = 0.6; 95% CI = 0.5--0.9), but no difference in the rates of CRBSI or BSI without a source. Chlorhexidine impregnated sponge dressings were associated with localized contact dermatitis in infants of very low birth weight. In 98 neonates with very low birth weight, 15 (15%) developed localized contact dermatitis; four (1.5%) of 237 neonates weighing >1,000 g developed this reaction (p < 0.0001). Infants with gestational age <26 weeks who had CVCs placed at age <8 days were at increased risk for having localized contact dermatitis, whereas no infants in the control group developed this local reaction [151].

Catheter securement

1. Use a sutureless securement device to reduce the risk of infection for intravascular catheters (147). Category II

Catheter stabilization is recognized as an intervention to decrease the risk of phlebitis, catheter migration and dislodgement, and may be advantageous in preventing CRBSIs. Pathogenesis of CRBSI occurs via migration of skin flora through the percutaneous entry site. Sutureless securement devices avoid disruption around the catheter entry site and may decrease the degree of bacterial colonization. (147). Using a sutureless securement device also mitigates the risk of sharps injury to the healthcare provider from inadvertent needlestick injury.

Dialysis catheter management

1. Use povidone iodine antiseptic ointment or bacitracin/ gramicidin/polymyxin B ointment at the hemodialysis catheter exit site after catheter insertion and at the end of each dialysis session only if this ointment does not interact with the material of the hemodialysis catheter per the manufacturer’s recommendation (64, 148–152). Category IB

2. Use prophylactic antimicrobial lock solution in patients with long term catheters who have a history of multiple CRBSI despite optimal maximal adherence to aseptic technique (153–169). Category II

A variety of topical antibiotic or antiseptic ointments have been utilized in attempts to lower the antimicrobial burden at the catheter insertion site and thus prevent infection. More recent studies have examined this approach in high-risk patients, particularly those undergoing hemodialysis (149–152). Three randomized, controlled trials have evaluated the use of 10% povidone iodine (150–152). A significant decrease in colonization, exit-site infection, or bloodstream infection was observed. The beneficial effect was most prominent in subjects with nasal colonization by Staphylococcus aureus (150–152).

In the only study demonstrating a significant effect on mortality, the application of bacitracin/gramicidin/polymyxin B ointment at the catheter insertion site was compared with placebo in 169 hemodialysis patients (170). There is evidence from this study that bacitracin/gramicidin/ polymyxin B ointment can improve outcome, but no similar data exist for use in other patient populations (170). Gramicidin-containing ointment is not currently available in the United States.

At least 10 studies regarding catheter flush or lock solutions have been performed in hemodialysis patients (160–169). Three meta-analyses have all demonstrated that catheter lock solutions reduce risk of CRBSI in hemodialysis patients (171–173). In the largest of these studies, 291 subjects were enrolled in a prospective randomized comparison of 30% trisodium citrate versus heparin (164). The rate of CRBSI was significantly lower in the group whose catheters were locked with trisodium citrate (4.1 BSI/1,000 CVC days vs. 1.1 BSI/1,000 CVC days, P< .001), and no significant difference in thrombosis or occlusion of the catheter was noted. However, if infused rapidly, concentrated citrate can result in serious hypocalcaemia, cardiac dysrhythmia, and death. The second largest study in hemodialysis subjects examined the effect of a catheter lock solution containing cefazolin, gentamicin, and heparin compared with control patients receiving only heparin (166). In 120 subjects, the rate of CRBSI was significantly lower in those receiving the antibiotic lock solution (0.44 BSI/1,000 CVC days vs. 3.12 BSI/1,000 CVC days, P = .03) (166). Other trials in hemodialysis patients have studied minocycline, gentamicin, EDTA, heparin, taurolidine, vancomycin, and cefotaxime.

Replacement of midline catheters

1. Replace midline catheters only when there is a specific indication. Category II

Midline catheters are associated with lower rates of phlebitis than short peripheral catheters and with lower rates of infection than CVCs (174–176). In one prospective study of 140 midline catheters, their use was associated with a BSI rate of 0.8 per 1,000 catheter days (176). No specific risk factors, including duration of catheterization, were associated with infection. Midline catheters were in place a median of 7 days, but for as long as 49 days. Although the findings of this study suggested that midline catheters could be changed only when there is a specific indication, no prospective, randomized studies have assessed the benefit of routine replacement as a strategy to prevent CRBSI associated with midline catheters.

Replacement of CVCs

1. Do not routinely replace CVCs, PICCs, hemodialysis catheters, or pulmonary artery catheters to prevent catheter-related infections. Category IB

2. Do not remove CVCs or PICCs on the basis of fever alone. Use clinical judgment regarding the appropriateness of removing the catheter if infection is evidenced elsewhere or if a noninfectious cause of fever is suspected. Category II

3. Do not use guidewire exchanges routinely for non-tunneled catheters to prevent infection. Category IB

4. Do not use guidewire exchanges to replace a non-tunneled catheter suspected of infection. Category IB

5. Use a guidewire exchange to replace a malfunctioning non-tunneled catheter if no evidence of infection is present. Category IB

6. Use new sterile gloves before handling the new catheter when guidewire exchanges are performed. Category II

Catheter replacement at scheduled time intervals as a method to reduce CRBSI has not lowered rates. Two trials have assessed a strategy of changing the catheter every 7 days compared with a strategy of changing catheters as needed (177, 178). One of these studies involved 112 surgical ICU patients who required CVCs, pulmonary artery catheters, or peripheral arterial catheters (177), whereas the other study involved only subclavian hemodialysis catheters (178). In both studies, no difference in CRBSI was observed in patients undergoing scheduled catheter replacement every 7 days compared with patients whose catheters were replaced as needed.

Scheduled guidewire exchange of CVCs is another proposed strategy for preventing CRBSI. The results of a meta-analysis of 12 randomized, controlled trials assessing CVC management failed to demonstrate any reduction of CRBSI rates through routine replacement of CVCs by guidewire exchange compared with catheter replacement on an as needed basis (179). Thus, routine replacement of CVCs is not necessary for catheters that are functioning and have no evidence of causing local or systemic complications.

Replacement of temporary catheters over a guidewire in the presence of bacteremia is not an acceptable replacement strategy because the source of infection is usually colonization of the skin tract from the insertion site to the vein (17, 180). However, in selected patients with tunneled hemodialysis catheters and bacteremia, catheter exchange over a guidewire, in combination with antibiotic therapy, is an alternative as a salvage strategy in patients with limited venous access (181–185).

The use of catheters for hemodialysis is the most common factor contributing to bacteremia in dialysis patients (186, 187). The relative risk for bacteremia in patients with dialysis catheters is seven times the risk for patients with arteriovenous (AV) fistulas (188). AV fistulas and grafts are preferred over hemodialysis catheters in patients with chronic renal failure, due to their lower associated risk of infection. If temporary access is needed for dialysis, a tunneled cuffed catheter is preferable to a non-cuffed catheter, even in the ICU setting, if the catheter is expected to stay in place for > 3 weeks (64).

Summary

The 2011 Guidelines for the Prevention of Intravascular Catheter-Related Infections contain comprehensive, current recommendations for the selection, placement, maintenance and replacement of catheters used for venous access. This material is directly relevant to the day-to-day practice of interventional radiology. Highlights of the Guidelines are presented here. The Guidelines contain additional recommendations related to pediatric use, arterial lines and other topics, and extensive background information and references. Review of the entire document is suggested for all physicians who perform venous access procedures.