OBJECTIVES: To assess the effects of skin antisepsis as part of CVC care for reducing catheter-related BSIs, catheter colonisation, and patient mortality and morbidities.

SEARCH METHODS: In May 2016 we searched: The Cochrane Wounds Specialised Register; The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations and Epub Ahead of Print); Ovid EMBASE and EBSCO CINAHL Plus. We also searched clinical trial registries for ongoing and unpublished studies. There were no restrictions with respect to language, date of publication or study setting.

SELECTION CRITERIA: We included randomised controlled trials (RCTs) that assessed any type of skin antiseptic agent used either alone or in combination, compared with one or more other skin antiseptic agent(s), placebo or no skin antisepsis in patients with a CVC in place.

DATA COLLECTION AND ANALYSIS: Two authors independently assessed the studies for their eligibility, extracted data and assessed risk of bias. We expressed our results in terms of risk ratio (RR), absolute risk reduction (ARR) and number need to treat for an additional beneficial outcome (NNTB) for dichotomous data, and mean difference (MD) for continuous data, with 95% confidence intervals (CIs).

MAIN RESULTS: Thirteen studies were eligible for inclusion, but only 12 studies contributed data, with a total of 3446 CVCs assessed. The total number of participants enrolled was unclear as some studies did not provide such information. The participants were mainly adults admitted to intensive care units, haematology oncology units or general wards. Most studies assessed skin antisepsis prior to insertion and regularly thereafter during the in-dwelling period of the CVC, ranging from every 24 h to every 72 h. The methodological quality of the included studies was mixed due to wide variation in their risk of bias. Most trials did not adequately blind the participants or personnel, and four of the 12 studies had a high risk of bias for incomplete outcome data.Three studies compared different antisepsis regimens with no antisepsis. There was no clear evidence of a difference in all outcomes examined, including catheter-related BSI, septicaemia, catheter colonisation and number of patients who required systemic antibiotics for any of the three comparisons involving three different antisepsis regimens (aqueous povidone-iodine, aqueous chlorhexidine and alcohol compared with no skin antisepsis). However, there were great uncertainties in all estimates due to underpowered analyses and the overall very low quality of evidence presented.There were multiple head-to-head comparisons between different skin antiseptic agents, with different combinations of active substance and base solutions. The most frequent comparison was chlorhexidine solution versus povidone-iodine solution (any base). There was very low quality evidence (downgraded for risk of bias and imprecision) that chlorhexidine may reduce catheter-related BSI compared with povidone-iodine (RR of 0.64, 95% CI 0.41 to 0.99; ARR 2.30%, 95% CI 0.06 to 3.70%). This evidence came from four studies involving 1436 catheters. None of the individual subgroup comparisons of aqueous chlorhexidine versus aqueous povidone-iodine, alcoholic chlorhexidine versus aqueous povidone-iodine and alcoholic chlorhexidine versus alcoholic povidone-iodine showed clear differences for catheter-related BSI or mortality (and were generally underpowered). Mortality was only reported in a single study.There was very low quality evidence that skin antisepsis with chlorhexidine may also reduce catheter colonisation relative to povidone-iodine (RR of 0.68, 95% CI 0.56 to 0.84; ARR 8%, 95% CI 3% to 12%; ; five studies, 1533 catheters, downgraded for risk of bias, indirectness and inconsistency).Evaluations of other skin antiseptic agents were generally in single, small studies, many of which did not report the primary outcome of catheter-related BSI. Trials also poorly reported other outcomes, such as skin infections and adverse events.

OBJECTIVES: Our main objective was to assess the effectiveness of antimicrobial impregnation, coating or bonding on CVCs in reducing clinically-diagnosed sepsis, catheter-related blood stream infection (CRBSI), all-cause mortality, catheter colonization and other catheter-related infections in adult participants who required central venous catheterization, along with their safety and cost effectiveness where data were available. We undertook the following comparisons: 1) catheters with antimicrobial modifications in the form of antimicrobial impregnation, coating or bonding, against catheters without antimicrobial modifications and 2) catheters with one type of antimicrobial impregnation against catheters with another type of antimicrobial impregnation. We planned to analyse the comparison of catheters with any type of antimicrobial impregnation against catheters with other antimicrobial modifications, e.g. antiseptic dressings, hubs, tunnelling, needleless connectors or antiseptic lock solutions, but did not find any relevant studies. Additionally, we planned to conduct subgroup analyses based on the length of catheter use, settings or levels of care (e.g. intensive care unit, standard ward and oncology unit), baseline risks, definition of sepsis, presence or absence of co-interventions and cost-effectiveness in different currencies.

SEARCH METHODS: We used the standard search strategy of the Cochrane Anaesthesia, Critical and Emergency Care Review Group (ACE). In the updated review, we searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 3), MEDLINE (OVID SP; 1950 to March 2015), EMBASE (1980 to March 2015), CINAHL (1982 to March 2015), and other Internet resources using a combination of keywords and MeSH headings. The original search was run in March 2012.

SELECTION CRITERIA: We included randomized controlled trials (RCTs) that assessed any type of impregnated catheter against either non-impregnated catheters or catheters with another type of impregnation in adult patients cared for in the hospital setting who required CVCs. We planned to include quasi-RCT and cluster-RCTs, but we identified none. We excluded cross-over studies.

DATA COLLECTION AND ANALYSIS: We extracted data using the standard methodological procedures expected by Cochrane. Two authors independently assessed the relevance and risk of bias of the retrieved records. We expressed our results using risk ratio (RR), absolute risk reduction (ARR) and number need to treat to benefit (NNTB) for categorical data and mean difference (MD) for continuous data, where appropriate, with their 95% confidence intervals (CIs).

MAIN RESULTS: We included one new study (338 participants/catheters) in this update, which brought the total included to 57 studies with 16,784 catheters and 11 types of impregnations. The total number of participants enrolled was unclear, as some studies did not provide this information. Most studies enrolled participants from the age of 18, including patients in intensive care units (ICU), oncology units and patients receiving long-term total parenteral nutrition. There were low or unclear risks of bias in the included studies, except for blinding, which was impossible in most studies due to the catheters that were being assessed having different appearances. Overall, catheter impregnation significantly reduced catheter-related blood stream infection (CRBSI), with an ARR of 2% (95% CI 3% to 1%), RR of 0.62 (95% CI 0.52 to 0.74) and NNTB of 50 (high-quality evidence). Catheter impregnation also reduced catheter colonization, with an ARR of 9% (95% CI 12% to 7%), RR of 0.67 (95% CI 0.59 to 0.76) and NNTB of 11 (moderate-quality evidence, downgraded due to substantial heterogeneity). However, catheter impregnation made no significant difference to the rates of clinically diagnosed sepsis (RR 1.0, 95% CI 0.88 to 1.13; moderate-quality evidence, downgraded due to a suspicion of publication bias), all-cause mortality (RR 0.92, 95% CI 0.80 to 1.07; high-quality evidence) and catheter-related local infections (RR 0.84, 95% CI 0.66 to 1.07; 2688 catheters, moderate quality evidence, downgraded due to wide 95% CI).In our subgroup analyses, we found that the magnitudes of benefits for impregnated CVCs varied between studies that enrolled different types of participants. For the outcome of catheter colonization, catheter impregnation conferred significant benefit in studies conducted in ICUs (RR 0.70;95% CI 0.61 to 0.80) but not in studies conducted in haematological and oncological units (RR 0.75; 95% CI 0.51 to 1.11) or studies that assessed predominantly patients who required CVCs for long-term total parenteral nutrition (RR 0.99; 95% CI 0.74 to 1.34). However, there was no such variation for the outcome of CRBSI. The magnitude of the effects was also not affected by the participants' baseline risks.There were no significant differences between the impregnated and non-impregnated groups in the rates of adverse effects, including thrombosis/thrombophlebitis, bleeding, erythema and/or tenderness at the insertion site.