A Systematic Review of the Impact of Antibiotic and Antimicrobial Catheter Locks on Catheter-Related Infections in Adult Patients Receiving Hemodialysis

Central venous catheter (CVC)-based hemodialysis is a major contributor to bacteremia in immunocompromised hosts. Heparin-locking CVCs is a frequent therapeutic procedure. However, it has not been shown to reduce catheter-related bloodstream infections (CRBSIs). For this systematic review, we searched PubMed, PubMed Central, ResearchGate, Science Direct, and Multidisciplinary Digital Publishing Institute (MDPI) for multiple articles published between January 2018 and January 2023 to determine how antimicrobial locking solutions affect CRBSIs, which could ultimately lower the risk of morbidity, mortality, and hospitalization costs. Antilocking products, catheter-related bacteremia, central-line associated bloodstream infections, tunneled dialysis catheter, hemodialysis, antibiotic, and antimicrobial catheter locks, and the Medical Subject Heading (MeSH) method for PubMed were used as the main keywords for searching publications. A pool of 13 studies with 46,139 individuals showed that the therapy group had a lower incidence of CRBSIs than the heparin-treated control group. Furthermore, it was discovered that bacteria were resistant to gentamicin, and the use of antibiotics had no discernible impact on catheter malfunction. In conclusion, the most effective locking solution to date is an antilocking solution made up of an antibiotic or antimicrobial agent combined with low-dose heparin (500-2,500 U/mL).

Heparin versus 0.9% sodium chloride locking for prevention of occlusion in central venous catheters in adults

BACKGROUND

Intermittent locking of central venous catheters (CVCs) is undertaken to help maintain their patency and performance. There are systematic variations in care: some practitioners use heparin (at different concentrations), whilst others use 0.9% sodium chloride (normal saline). This review looks at the effectiveness and safety of intermittent locking with heparin compared to normal saline, to see if the evidence establishes whether one is better than the other. This is an update of an earlier Cochrane Review.

OBJECTIVES

To evaluate the benefits and harms of intermittent locking of CVCs with heparin versus normal saline in adults to prevent occlusion.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 20 October 2021.

SELECTION CRITERIA

We included randomised controlled trials in adults ≥ 18 years of age with a CVC that compared intermittent locking with heparin at any concentration versus normal saline. We excluded studies on infants and children from this review.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were occlusion of CVCs and duration of catheter patency. Our secondary outcomes were CVC-related bloodstream infections and CVC-related colonisation, mortality, haemorrhage, heparin-induced thrombocytopaenia, CVC-related thrombosis, number of additional CVC insertions, abnormality of coagulation profile and allergic reactions to heparin. We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

We identified one new RCT with 30 participants for this update. We included a total of 12 RCTs with 2422 participants. Data for meta-analysis were available from all RCTs. We noted differences in methods used by the included studies and variation in heparin concentrations (10 to 5000 IU/mL), time to follow-up (1 to 251.8 days), and the unit of analysis used (participant, catheter, line access). Five studies included ICU (intensive care unit) patients, two studies included oncology patients, and the remaining studies included miscellaneous patients (chronic kidney disease, haemodialysis, home care patients, etc.). Primary outcomes Overall, combined results may show fewer occlusions with heparin compared to normal saline but this is uncertain (risk ratio (RR) 0.70, 95% confidence interval (CI) 0.51 to 0.95; 10 studies; 1672 participants; low-certainty evidence). We pooled studies that used participant or catheter as the unit of analysis. We carried out subgroup analysis by unit of analysis. No clear differences were detected after testing for subgroup differences (P = 0.23). We found no clear evidence of a difference in the duration of catheter patency with heparin compared to normal saline (mean difference (MD) 0.44 days, 95% CI -0.10 to 0.99; 6 studies; 1788 participants; low-certainty evidence). Secondary outcomes We found no clear evidence of a difference in the following outcomes: CVC-related bloodstream infections (RR 0.66, 95% CI 0.08 to 5.80; 3 studies; 1127 participants; very low-certainty evidence); mortality (RR 0.76, 95% CI 0.44 to 1.31; 3 studies; 1100 participants; very low-certainty evidence); haemorrhage (RR 1.54, 95% CI 0.41 to 5.74; 3 studies; 1197 participants; very low-certainty evidence); or heparin-induced thrombocytopaenia (RR 0.21, 95% CI 0.01 to 4.27; 3 studies; 443 participants; very low-certainty evidence). The main reasons for downgrading the certainty of evidence for the primary and secondary outcomes were unclear allocation concealment, suspicion of publication bias, imprecision and inconsistency.

AUTHORS' CONCLUSIONS

Given the low-certainty evidence, we are uncertain whether intermittent locking with heparin results in fewer central venous catheter occlusions than intermittent locking with normal saline in adults. Low-certainty evidence suggests that heparin may have little or no effect on catheter patency duration. Although we found no evidence of differences in safety (CVC-related bloodstream infections, mortality, or haemorrhage), the combined studies were not powered to detect rare adverse events such as heparin-induced thrombocytopaenia. Further research conducted over longer periods would reduce the current uncertainties.

Locked Away-Prophylaxis and Management of Catheter Related Thrombosis in Hemodialysis

Reliable vascular access is necessary for effective hemodialysis. Guidelines recommend chronic hemodialysis via an arteriovenous fistula (AVF), however, in a significant number of patients, permanent central venous catheters (CVCs) are used. The use of a tunneled catheter is acceptable if the estimated dialysis time is less than a year or it is not possible to create an AVF. The main complications associated with CVC include thrombosis and catheter-related bloodstream infections (CRBSIs), which may result in loss of vascular access. The common practice is to use locking solutions to maintain catheter patency and minimize the risk of CRBSI. This paperwork summarizes information on currently available locking solutions for dialysis catheters along with their effectiveness in preventing thrombotic and infectious complications and describes methods of dealing with catheter dysfunction. The PubMed database was systematically searched for articles about locking solutions used in permanent CVCs in hemodialysis patients. Additional studies were identified by searching bibliographies and international guidelines. Articles on end-stage kidney disease patients dialyzed through a permanent CVC were included. Information from each primary study was extracted using pre-determined criteria including thrombotic and infectious complications of CVC use, focusing on permanent CVC if sufficient data were available. Of the currently available substances, it seems that citrate at a concentration of 4% has the best cost-effectiveness and safety profile, which is reflected in the international guidelines. Recent studies suggest the advantage of 2+1 protocols, i.e., taurolidine-based solutions with addition of urokinase once a week, although it needs to be confirmed by further research. Regardless of the type of locking solution, if prophylaxis with a thrombolytic agent is chosen, it should be started from the very beginning to reduce the risk of thrombotic complications. In case of CVC dysfunction, irrespective of the thrombolysis attempt, catheter replacement should be planned as soon as possible.

KDOQI Clinical Practice Guideline for Vascular Access: 2019 Update

The National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (KDOQI) has provided evidence-based guidelines for hemodialysis vascular access since 1996. Since the last update in 2006, there has been a great accumulation of new evidence and sophistication in the guidelines process. The 2019 update to the KDOQI Clinical Practice Guideline for Vascular Access is a comprehensive document intended to assist multidisciplinary practitioners care for chronic kidney disease patients and their vascular access. New topics include the end-stage kidney disease "Life-Plan" and related concepts, guidance on vascular access choice, new targets for arteriovenous access (fistulas and grafts) and central venous catheters, management of specific complications, and renewed approaches to some older topics. Appraisal of the quality of the evidence was independently conducted by using a Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach, and interpretation and application followed the GRADE Evidence to Decision frameworks. As applicable, each guideline statement is accompanied by rationale/background information, a detailed justification, monitoring and evaluation guidance, implementation considerations, special discussions, and recommendations for future research.

Comparative efficacy and safety of lock solutions for the prevention of catheter-related complications including infectious and bleeding events in adult haemodialysis patients: a systematic review and network meta-analysis

BACKGROUND

Central venous catheters are used extensively as temporary or permanent vascular access for haemodialysis patients. Catheter-related bloodstream infections are the main complication of central venous catheters and increase morbidity and mortality in haemodialysis patients.

OBJECTIVES

The aim was to assess the most appropriate lock solution for central venous catheters to prevent catheter-related bloodstream infections and other complications.

DATA SOURCES

Medline, Embase and the Cochrane Central Register of Controlled Trials from the date of their inception to August 2018 were used as data sources. The reference lists of eligible studies and relevant reviews were also checked.

STUDY ELIGIBILITY CRITERIA AND PARTICIPANTS

Randomized controlled trials (RCTs) comparing different lock solutions for the prevention of central venous catheter-related infectious and bleeding complications for adult dialysis patients were included.

INTERVENTIONS

Interventions were lock solutions for haemodialysis catheters.

METHODS

The primary outcomes were catheter-related bloodstream infections and bleeding events. The secondary outcomes were catheter malfunction, exit-site infection, and all-cause mortality. We estimated summary risk ratios (RRs) using pairwise and network meta-analysis. We assessed the risk of bias of individual studies with the Cochrane risk of bias tool.

RESULTS

Forty-nine trials (7020 patients) were included for this study. Compared with heparin 5000 U/mL, antibiotic locks (antibiotics with trisodium citrate (TSC), ethylenediamine tetraacetic acid (EDTA), heparin 5000 U/mL, low-dose heparin or urokinase) and ethanol locks were more effective in preventing catheter-related bloodstream infections. Antimicrobial agents plus low-dose heparin (500-2500 U/mL), TSC and low-dose heparin locks had lower risk of bleeding events than heparin 5000 U/mL. None of the lock solutions reduced rates of catheter malfunction and all-cause mortality compared with heparin 5000 U/mL. In summary, antibiotics plus low-dose heparin was ranked as the best lock solution. The overall results were not materially changed in sensitivity analyses.

CONCLUSIONS

Taking into account both efficacy and safety, antibiotics plus low-dose heparin (500-2500 U/mL) may be the preferred lock solution.

Trisodium citrate 4% versus heparin as a catheter lock for non-tunneled hemodialysis catheters in critically ill patients: a multicenter, randomized clinical trial

Background

Non-tunneled hemodialysis catheters are currently used for critically ill patients with acute kidney injury requiring extracorporeal renal replacement therapy. Strategies to prevent catheter dysfunction and infection with catheter locks remain controversial.

Methods

In a multicenter, randomized, controlled, double-blind trial, we compared two strategies for catheter locking of non-tunneled hemodialysis catheters, namely trisodium citrate at 4% (intervention group) versus unfractionated heparin (control group), in patients aged 18 years or older admitted to the intensive care unit and in whom a first non-tunneled hemodialysis catheter was to be inserted by the jugular or femoral vein. The primary endpoint was length of event-free survival of the first non-tunneled hemodialysis catheter. Secondary endpoints were: rate of fibrinolysis, incidence of catheter dysfunction and incidence of catheter-related bloodstream infection (CRBSI), all per 1000 catheter-days; number of hemorrhagic events requiring transfusion, length of stay in intensive care and in hospital; 28-day mortality.

Results

Overall, 396 randomized patients completed the trial: 199 in the citrate group and 197 in the heparin group. There was no significant difference in baseline characteristics between groups. The duration of event-free survival of the first non-tunneled hemodialysis catheter was not significantly different between groups: 7 days (IQR 3–10) in the citrate group and 5 days (IQR 3–11) in the heparin group (p = 0.51). Rates of catheter thrombosis, CRBSI, and adverse events were not statistically different between groups.

Conclusions

In critically ill patients, there was no significant difference in the duration of event-free survival of the first non-tunneled hemodialysis catheter between trisodium citrate 4% and heparin as a locking solution. Catheter thrombosis, catheter-related infection, and adverse events were not statistically different between the two groups.

Trial registration Registered with Clinicaltrials.gov under the number NCT01962116. Registered 14 October 2013.

Electronic supplementary material

The online version of this article (10.1186/s13613-019-0553-4) contains supplementary material, which is available to authorized users.

Heparin versus 0.9% sodium chloride locking for prevention of occlusion in central venous catheters in adults

BACKGROUND

Intermittent locking of central venous catheters (CVCs) is undertaken to help maintain their patency. There are systematic variations in care: some practitioners use heparin (at different concentrations), whilst others use 0.9% NaCl (normal saline). This review looks at the effectiveness and safety of intermittent locking with heparin compared to 0.9% NaCl to see if the evidence establishes whether one is better than the other. This work is an update of a review first published in 2014.

OBJECTIVES

To assess the effectiveness and safety of intermittent locking of CVCs with heparin versus normal saline (NS) in adults to prevent occlusion.

SEARCH METHODS

The Cochrane Vascular Information Specialist (CIS) searched the Specialised Register (last searched 11 June 2018) and the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 5). Searches were also carried out in MEDLINE, Embase, CINAHL, and clinical trials databases (11 June 2018).

SELECTION CRITERIA

We included randomised controlled trials in adults ≥ 18 years of age with a CVC that compared intermittent locking with heparin at any concentration versus NS. We applied no restriction on language.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, assessed quality, and extracted data. We contacted trial authors to retrieve additional information, when necessary. We carried out statistical analysis using Review Manager 5 and assessed the overall quality of the evidence supporting assessed outcomes using GRADE. We carried out prespecified subgroup analysis.

MAIN RESULTS

We identified five new studies for this update (six prior studies were included in the original review), bringing the number of eligible studies to 11, with a total of 2392 participants. We noted differences in methods used by the included studies and variation in heparin concentrations (10 to 5000 IU/mL), time to follow-up (1 to 251.8 days), and the unit of analysis used (participant, catheter, line access).Combined results from these studies showed fewer occlusions with heparin than with NS (risk ratio (RR) 0.70, 95% confidence interval (CI) 0.51 to 0.95; P = 0.02; 1672 participants; 1025 catheters from 10 studies; I² = 14%) and provided very low-quality evidence.We carried out subgroup analysis by unit of analysis (testing for subgroup differences (P = 0.23; I² = 30.3%). When the unit of analysis was the participant, results show no clear differences in all occlusions between heparin and NS (RR 0.79, 95% CI 0.58 to 1.08; P = 0.15; 1672 participants; seven studies). Subgroup analysis using the catheter as the unit of analysis shows fewer occlusions with heparin use (RR 0.53, 95% CI 0.29 to 0.95; P = 0.03; 1025 catheters; three studies). When the unit of analysis was line access, results show no clear differences in occlusions between heparin and NS (RR 1.08, 95% CI 0.84 to 1.40; 770 line accesses; one study).We found no clear differences in the duration of catheter patency (mean difference (MD) 0.44 days, 95% CI -0.10 to 0.99; P = 0.11; 1036 participants; 752 catheters; six studies; low-quality evidence).We found no clear evidence of a difference in the following: CVC-related sepsis (RR 0.74, 95% CI 0.03 to 19.54; P = 0.86; 1097 participants; two studies; low-quality evidence); mortality (RR 0.76, 95% CI 0.44 to 1.31; P = 0.33; 1100 participants; three studies; low-quality evidence); haemorrhage at any site (RR 1.32, 95% CI 0.57 to 3.07; P = 0.52; 1245 participants; four studies; moderate-quality evidence); or heparin-induced thrombocytopaenia (RR 0.21, 95% CI 0.01 to 4.27; P = 0.31; 443 participants; three studies; low-quality evidence).The main reasons for downgrading the quality of evidence were unclear allocation concealment, imprecision, and suspicion of publication bias.

AUTHORS' CONCLUSIONS

Given the very low quality of the evidence, we are uncertain whether intermittent locking with heparin results in fewer occlusions than intermittent locking with NS. Low-quality evidence suggests that heparin may have little or no effect on catheter patency. Although we found no evidence of differences in safety (sepsis, mortality, or haemorrhage), the combined trials are not powered to detect rare adverse events such as heparin-induced thrombocytopaenia.

Hemodialysis Catheter-Related Central Venous Thrombosis: Clinical Approach to Evaluation and Management

Central venous catheter (CVC) use is common among patients undergoing hemodialysis. Catheter-related vascular thrombosis is a frequent complication, which results in catheter dysfunction. This may eliminate the affected vein as a potential route of vascular access and leads to significant morbidity of the limbs involved. Despite increasing prevalence, there is a dearth of evidence-based guidelines for managing such catheter-related thrombi, often leading to treatment dilemmas in clinical practice. Minimizing the use of CVCs for hemodialysis remains the best approach in preventing such adverse complications. Furthermore, meticulous planning and care when using such catheters in unavoidable circumstances along with vigilant surveillance to identify complications early will allow to avoid associated morbidity.

Antimicrobial lock solutions for preventing catheter-related infections in haemodialysis

BACKGROUND

Patients undergoing haemodialysis (HD) through a central venous catheter (CVC) are exposed to several risks, being a catheter-related infection (CRI) and a CVC lumen thrombosis among the most serious. Standard of care regarding CVCs includes their sealing with heparin lock solutions to prevent catheter lumen thrombosis. Other lock solutions to prevent CRI, such as antimicrobial lock solutions, have proven useful with antibiotics solutions, but not as yet for non-antibiotic antimicrobial solutions. Furthermore, it is uncertain if these solutions have a negative effect on thrombosis incidence.

OBJECTIVES

To assess the efficacy and safety of antimicrobial (antibiotic, non-antibiotic, or both) catheter lock solutions for preventing CRI in participants undergoing HD with a CVC.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register up to 18 December 2017 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov.

SELECTION CRITERIA

We included all randomised or quasi-randomised control trials (RCTs) comparing antimicrobial (antibiotic and non-antibiotic) lock solutions to standard lock solutions, in participants using a CVC for HD, without language restriction.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for eligibility, and two additional authors assessed for risk of bias and extracted data. We expressed results as rate ratios (RR) per 1000 catheter-days or 1000 dialysis sessions with 95% confidence intervals (CI). Statistical analyses were performed using the random-effects model.

MAIN RESULTS

Thirty-nine studies, enrolling 4216 participants, were included in this review, however only 30 studies, involving 3392 participants, contained enough data to be meta-analysed. Risk of bias was low or unclear for most domains in the majority of the included studies.Studies compared antimicrobial lock solutions (antibiotic and non-antibiotic) to standard sealing solutions (usually heparin) of the CVC for HD. Fifteen studies used antibiotic lock solutions, 21 used non-antibiotic antimicrobial lock solutions, and 4 used both (antibiotic and non-antibiotic) lock solutions. Studies reported the incidence of CRI, catheter thrombosis, or both.Antimicrobial lock solutions probably reduces CRI per 1000 catheter-days (27 studies: RR 0.38, 95% CI 0.27 to 0.53; I² = 54%; low certainty evidence), however antimicrobial lock solutions probably makes little or no difference to the risk of thrombosis per 1000 catheter days (14 studies: RR 0.79, 95% CI 0.52 to 1.22; I² = 83%; very low certainty evidence). Subgroup analysis of antibiotic and the combination of both lock solutions showed that both probably reduced CRI per 1000 catheter-days (13 studies: RR 0.30, 95% CI: 0.22 to 0.42; I² = 47%) and risk of thrombosis per 1000 catheter-days (4 studies: RR 0.26, 95% CI: 0.14 to 0.49; I² = 0%), respectively. Non-antibiotic antimicrobial lock solutions probably reduced CRI per 1000 catheter-days for tunnelled CVC (9 studies: RR 0.60, 95% CI 0.40 to 0.91) but probably made little or no difference with non-tunnelled CVC (4 studies: RR 0.93, 95% CI 0.48 to 1.81). Subgroup analyses showed that antibiotic (5 studies: RR 0.76, 95% CI 0.42 to 1.38), non-antibiotic (8 studies: RR 0.85, 95% CI 0.44 to 1.66), and the combination of both lock solutions (3 studies: RR 0.63, 95% CI 0.22 to 1.81) made little or no difference to thrombosis per 1000 catheter-days compared to control lock solutions.

AUTHORS' CONCLUSIONS

Antibiotic antimicrobial and combined (antibiotic-non antibiotic) lock solutions decreased the incidence of CRI compared to control lock solutions, whereas non-antibiotic lock solutions reduce CRI only for tunnelled CVC. The effect on thrombosis incidence is uncertain for all antimicrobial lock solutions. Our confidence in the evidence is low and very low; therefore, better-designed studies are needed to confirm the efficacy and safety of antimicrobial lock solutions.

[Comparison of citrate 4% and heparin as tunneled-catheters-locking solution in chronic hemodialysis]

INTRODUCTION

Citrate 4% is an alternative to heparin as catheter-locking solution in chronic hemodialysis patients. We compared catheter dysfunction episodes, dialysis adequacy, plasminogen-tissular activators use and costs according to catheter-locking solution in our centre.

METHODS

Prospective, monocentric, cohort study (NephroCare Tassin-Charcot) on 49 prevalent patients in chronic hemodialysis. Two main groups were formed according to the prescription of catheter-locking solution at the beginning of the study (03/02/2016) and followed until 05/10/2016: heparin (n=26) and citrate (n=22).

RESULTS

The number of diabetic patients was higher in the citrate group (12/22) than in the heparin one (5/26; P=0.025). The 2 groups were comparable for the other studied variables. We didn't observe any difference in terms of catheter-dysfunction (4.23 versus 4.14% in heparin and citrate groups, respectively; P=1.0) and dialysis adequacy. The prescription of citrate was associated with lower TPA uses (1/604 versus 14/946; P=0.022) and lower costs (1.42 € for one session versus 2.94 €).

CONCLUSION

Administration of citrate 4% as a catheter-locking solution is not inferior to heparin in terms of catheter-dysfunction episodes, is associated with similar dialysis adequacy results, lower plasminogen-tissular activators uses and reduced costs in chronic prevalent hemodialysed patients.

Urokinase-containing locking solution in the prevention of dialysis catheter dysfunction: a double blind randomized controlled trial

INTRODUCTION

The prophylactic use of recombinant tissue plasminogen activator once weekly reduces the incidence rate of tunneled cuffed catheter (TCC) malfunction and bacteremia as compared to the exclusive use of heparin as locking solution. Restricting the use of prophylactic thrombolytic agents to patients with a history of thrombotic TCC malfunction could be more cost effective. We conduct a multicenter, double-blind, randomized controlled trial and test the hypothesis that weekly use of urokinase lock will reduce the incidence of thrombotic malfunction by 50% in prevalent hemodialysis patients with a history of thrombotic malfunction.

METHODS

Patients with a history of at least two separate TCC thrombotic dysfunctions treated with urokinase lock during the 6 months preceding inclusion are recruited in eight Belgian dialysis units. Patients are randomized in two groups: the control group receiving Taurolock™-HEP500 (heparin 500 IU/mL, taurolidine, citrate 4%) after each hemodialysis session and the treatment group receiving Taurolock-U 25,000 (urokinase 25,000, taurolidine, citrate 4%) once a week and the standard Taurolock-HEP500 at the end of the two others sessions. The primary outcome is the incidence rate of TCC thrombotic dysfunction defined by the use of urokinase. The secondary outcomes are the incidence rate of TCC removal and systemic thrombolysis. For the study, both patients and healthcare staff are blinded to treatment allocation.

CONCLUSIONS

The present trial is the first to investigate the effect of Taurolock-U 25,000 catheter lock once a week as secondary prevention in hemodialysis patients with the highest risk of TCC-related thrombotic dysfunction.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02036255.

Anticoagulants and antiplatelet agents for preventing central venous haemodialysis catheter malfunction in patients with end-stage kidney disease

BACKGROUND

Catheter malfunction, including thrombosis, is associated with reduced dialysis adequacy, as well as an increased risk of catheter-related bacteraemia and mortality. The role of anticoagulants in the prevention of catheter malfunction remains uncertain.

OBJECTIVES

This review aimed to compare the prophylactic effect of different anticoagulant agents, preparations, doses and administration on the incidence of central venous haemodialysis catheter-related malfunction and sepsis in patients with end-stage kidney disease (ESKD).

SEARCH METHODS

We searched the Cochrane Renal Group's Specialised Register to 7 January 2016 through contact with the Trials' Search Co-ordinator using search terms relevant to this review.

SELECTION CRITERIA

We included all randomised controlled trials (RCT) assessing anticoagulants compared with conventional care for the prevention of catheter malfunction in adult patients receiving haemodialysis for ESKD.

DATA COLLECTION AND ANALYSIS

The primary outcome was catheter malfunction defined as a catheter blood flow of 200 mL/min or less, or as defined by study authors. Secondary outcomes were catheter-related bacteraemia, all-cause mortality and bleeding events. Relative risks (RR) with 95% confidence intervals (CI) for individual studies were pooled using random effects models within treatment classes. Analyses were conducted by class, with subgroup analyses performed of individual agents within classes.

MAIN RESULTS

We included 27 studies (3003 participants) that were followed up for a median of six months. Study interventions included alternative anticoagulant locking solutions (19 studies, 2216 patients), systemic agents (6 studies, 664 patients) and low or no dose heparin (2 studies, 123 patients). The most common comparison treatment was a locking solution of heparin 5000 IU/mL, used in 17 studies. No significant effect on catheter malfunction was observed for alternative anticoagulant locking solutions (RR 0.96, 95% CI 0.74 to 1.26), systemic agents (RR 0.59, 95% CI 0.28 to 1.23), or low or no dose heparin (RR 0.90, 95% CI 0.10 to 8.31). A significant reduction on incidence of catheter-related bacteraemia was observed for alternative anticoagulant locking solutions (RR 0.46, 95% CI 0.32 to 0.66) but not systemic agents (RR 2.41, 95% CI 0.89 to 6.55), and could not be assessed in reports of low or no dose heparin studies. No significant effect on all-cause mortality was observed for alternative anticoagulant locking solutions (RR 0.88, 95% CI 0.54 to 1.43) or systemic agents (RR 0.78, 95% CI 0.37 to 1.65), and was not reported in studies of low or no dose heparin. Bleeding events were only reported in eight studies, including only 2/5 studies of systemic warfarin, with no clear effect demonstrated (RR 1.43, 95% CI 0.86 to 2.39). For individual agents, recombinant tissue plasminogen (rt-PA) was the only locking solution shown to reduce catheter malfunction (RR 0.58, 95% CI 0.37 to 0.91) based on the results of a single study. No significant on catheter malfunction was observed for other individual classes of alternative anticoagulant locking solutions (citrate: RR 1.14, 95% CI 0.76 to 1.69; antibiotic: RR 1.48, 95% CI 0.79 to 2.77; ethanol: RR 0.88, 95% CI 0.21 to 3.67). On the other hand, all individual classes of alternative anticoagulant locking solutions, except ethanol, reduced catheter-related bacteraemia (citrate: RR 0.49, 95% CI 0.36 to 0.68; antibiotic: RR 0.27, 95% CI 0.11 to 0.70; rt-PA: RR 0.35, 95% CI 0.13 to 0.93; ethanol: RR 0.33, 95% CI 0.03 to 4.05). No significant effect on all-cause mortality was observed for any individual agent within the class of alternative locking solutions. Studies were mainly of low quality and underpowered with an average participant number of 75 and study duration of six months. The interpretation of the study evidence was further limited by the variation in tested interventions and outcome reporting.

AUTHORS' CONCLUSIONS

The relative net benefit of anticoagulant therapies for prevention of catheter malfunction remains uncertain. Multiple agents appear to reduce catheter-related bacteraemia although the lack of clear assessment of harms and the limitations of study quality mean these results should be interpreted with caution. Methodological approaches can be used to avoid methods of reporting unduly affecting on the results of meta-analyses incorporating studies employed mixed reporting methods. Further high quality randomised studies, including safety outcomes, are needed.

Benefits and harms of citrate locking solutions for hemodialysis catheters: a systematic review and meta-analysis

BACKGROUND

Citrate has theoretical advantages over heparin for locking hemodialysis central venous catheters (CVCs), but the comparative effectiveness of these agents is not clear.

OBJECTIVES

1) To compare the benefits and harms of citrate versus heparin locking solutions among patients undergoing hemodialysis through CVCs; 2) to appraise methodological quality of the supporting evidence.

DATA SOURCES

CENTRAL, MEDLINE, EMBASE, CINAHL, ISI Web of Science, and nephrology conference abstracts.

STUDY ELIGIBILITY PARTICIPANTS AND INTERVENTIONS

We included randomized, parallel arm clinical trials that enrolled adult patients (>18 years) receiving chronic hemodialysis through CVCs using a citrate locking solution. We excluded studies in which citrate was combined with other agents, such as antibiotics.

APPRAISAL AND SYNTHESIS METHODS

We used the GRADE approach to systematic reviews and quality appraisal. Two reviewers performed data extraction independently and in duplicate. We pooled count data using generic inverse variance with random-effects models, and used fixed-effect models when only two studies were available for pooling. Subgroups included low (≤5%) vs. higher (≥30%) citrate.

RESULTS

We screened 600 citations. Forty-one proceeded to full-text screen; 5 met inclusion criteria. Studies included between 19 and 291 participants (Median N = 61) followed for a total of 174.6 catheter-years; 2 were multi-centred trials. Three studies assessed all-cause mortality; the pooled relative risk for death was 0.71 (95% CI = 0.42-1.24; p = 0.21; I(2) = 0%). The rate ratio for bacteremic episodes was 0.54 (95% CI = 0.23-1.29; p = 0.16; I(2) = 65%) while the rate ratio for bleeding was 0.48 (95% CI = 0.3-0.75; p = 0.001;I I(2) = 5%). Rates of catheter exchange/replacement, all-cause hospitalization and in-situ thrombolysis were not significantly different between groups in any of the pooled analyses. Risk of bias within pooled studies was low.

LIMITATIONS

Outcome definitions varied across studies. Imprecision due to small sample sizes and low event rates reduce our overall confidence in the pooled effect estimates.

IMPLICATIONS

Benefits and harms of citrate vs. heparin locking solutions remain unclear; larger studies and standardization of outcome measurement and reporting are warranted.

TRIAL REGISTRATION

Protocol Registration Number: CRD42013004781.

Heparin versus 0.9% sodium chloride intermittent flushing for prevention of occlusion in central venous catheters in adults

BACKGROUND

Heparin intermittent flushing is a standard practice in the maintenance of patency in central venous catheters. However, we could find no systematic review examining its effectiveness and safety.

OBJECTIVES

To assess the effectiveness of intermittent flushing with heparin versus 0.9% sodium chloride (normal saline) solution in adults with central venous catheters in terms of prevention of occlusion and overall benefits versus harms.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched December 2013) and the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 11). Searches were also carried out in MEDLINE, EMBASE, CINAHL and clinical trials databases (December 2013).

SELECTION CRITERIA

Randomised controlled trials (RCTs) in adults 18 years of age and older with a central venous catheter (CVC) in which intermittent flushing with heparin (any dose with or without other drugs) was compared with 0.9% normal saline were included. No restriction on language was applied.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, assessed trial quality and extracted data. Trial authors were contacted to retrieve additional information, when necessary.

MAIN RESULTS

Six eligible studies with a total of 1433 participants were included. The heparin concentrations used in these studies were very different (10-5000 IU/mL), and follow-up varied from 20 days to 180 days. The overall risk of bias in the studies was low. The quality of the evidence ranged from very low to moderate for the main outcomes (occlusion of CVC, duration of catheter patency, CVC-related sepsis, mortality and haemorrhage at any site).Combined findings from three trials in which the unit of analysis was the catheter suggest that heparin was associated with reduced CVC occlusion rates (risk ratio (RR) 0.53, 95% confidence interval (CI) 0.29 to 0.94). However, no clear evidence of a similar effect was found when the results of two studies in which the unit of analysis was the participant were combined (RR 0.21, 95% CI 0.03 to 1.70), nor when findings were derived from one study, which considered total line accesses (RR 1.08, 95% CI 0.84 to 1.40). Furthermore, results for other estimated effects were found to be imprecise and compatible with benefit and harm: catheter duration in days (mean difference (MD) 0.41, 95% CI -1.29 to 2.12), CVC-related thrombosis (RR 1.22, 95% CI 0.74 to 1.99), CVC-related sepsis (RR 1.02, 95% CI 0.34 to 3.03), mortality (RR 0.77, 95% CI 0.45 to 1.32) and haemorrhage at any site (RR 1.37, 95% CI 0.49 to 3.85).

AUTHORS' CONCLUSIONS

We found no conclusive evidence of important differences when heparin intermittent flushing was compared with 0.9% normal saline flushing for central venous catheter maintenance in terms of efficacy or safety. As heparin is more expensive than normal saline, our findings challenge its continued use in CVC flushing outside the context of clinical trials.

Citrate versus heparin lock for hemodialysis catheters: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Citrate solution has been suggested as an effective and safe catheter lock in hemodialysis. However, whether a citrate lock is superior to a heparin lock in preventing catheter-related infections and maintaining catheter patency is inconclusive.

STUDY DESIGN

A systematic review and meta-analysis was performed by searching in PubMed, EMBASE, Ovid, the Cochrane Library, and Web of Science databases and major nephrology journals.

SETTING & POPULATION

Patients receiving hemodialysis with central venous catheters.

SELECTION CRITERIA FOR STUDIES

Randomized controlled trials comparing citrate locks with heparin locks in hemodialysis patients with central venous catheters.

INTERVENTION

Locking central venous catheters with citrate locks.

OUTCOMES

Primary outcomes include catheter-related bloodstream infection (CRBSI), exit-site infection, catheter removal for poor flow, and thrombolytic treatment.

RESULTS

13 randomized controlled trials (1,770 patients, 221,064 catheter-days) met the inclusion criteria. Pooled analyses found that citrate locks could significantly reduce the incidence of CRBSI (risk ratio [RR], 0.39; 95% CI, 0.27-0.56; P < 0.001). Subgroup analysis showed that antimicrobial-containing citrate locks (citrate + gentamicin, citrate + taurolidine, and citrate + methylene blue + methylparaben + propylparaben) were superior to heparin locks in the prevention of CRBSI (P < 0.001, P = 0.003, and P = 0.008, respectively), whereas citrate alone failed to show a similar advantage (P = 0.2). Low- (1.04%-4%) to moderate-concentration (4.6%-7%) citrate locks were associated with decreased CRBSI incidence (P < 0.001 and P = 0.003, respectively), but patients receiving high-concentration (30%-46.7%) citrate and heparin locks had similar incidences (P = 0.3). The incidence of bleeding episodes (RR, 0.48; 95% CI, 0.30-0.76; P = 0.002) was significantly lower in patients receiving citrate locks, whereas both groups were similar in terms of exit-site infection (P = 0.2), catheter removal for poor flow (P = 0.9), thrombolytic treatment (P = 0.8), all-cause death (P = 0.3), catheter thrombosis (P = 0.9), mean catheter duration (P = 0.2), CRBSI-free catheter survival (P = 0.2), and catheter-related readmission (P = 0.5).

LIMITATIONS

All studies used in the meta-analysis were performed in Western countries. The applicability of our findings to other regions remains to be clarified.

CONCLUSIONS

An antimicrobial-containing citrate lock is better than a heparin lock in the prevention of catheter-related infection, while citrate alone fails to show a similar advantage. Citrate locks of low to moderate concentrations, rather than high concentration, were superior to heparin locks in preventing CRBSI. Citrate locks also might decrease bleeding episodes. No difference has been identified in the efficacy to prevent exit-site infection or preserve catheter patency between citrate and heparin locks.

Minimizing hemodialysis catheter dysfunction: an ounce of prevention

The maintenance of tunneled catheter (TC) patency is critical for the provision of adequate hemodialysis in patients who are TC-dependent. TC dysfunction results in the need for costly and inconvenient interventions, and reduced quality of life. Since the introduction of TCs in the late 1980s, heparin catheter lock has been the standard prophylactic regimen for the prevention of TC dysfunction. More recently, alternative catheter locking agents have emerged, and in some cases have shown to be superior to heparin lock with respect to improving TC patency and reducing TC-associated infections. These include citrate, tissue plasminogen activator, and a novel agent containing sodium citrate, methylene blue, methylparaben, and propylparaben. In addition, prophylaxis using oral anticoagulants/antiplatelet agents, including warfarin, aspirin, ticlodipine, as well as the use of modified heparin-coated catheters have also been studied for the prevention of TC dysfunction with variable results. The use of oral anticoagulants and/or antiplatelet agents as primary or secondary prevention of TC dysfunction must be weighed against their potential adverse effects, and should be individualized for each patient.

Sodium citrate versus saline catheter locks for non-tunneled hemodialysis central venous catheters in critically ill adults: a randomized controlled trial

PURPOSE

Sodium citrate has antibacterial and anticoagulant properties that are confined to the catheter when used as a catheter lock. Studies of its use as a catheter lock in chronic hemodialysis patients suggest it may be efficacious in preventing infection and thrombotic complications. We compared sodium citrate with saline catheter locks for non-tunneled hemodialysis central venous catheters in critically ill adult patients. Primary endpoint was catheter life span without complication.

METHODS

This was a randomized, controlled, open-label trial involving intensive care patients with acute renal failure requiring hemodialysis. Events were defined as catheter-related bloodstream infection and catheter malfunction.

RESULTS

Seventy-eight patients were included. Median catheter life span without complication was 6 days (saline group) versus 12 days (citrate group) [hazard ratio (HR) 2.12 (95% CI 1.32-3.4), p = 0.0019]. There was a significantly higher rate of catheter malfunction in the saline group compared with in the citrate group (127 catheter events/1,000 catheter-days, saline group vs. 26 events/1,000 catheter-days, citrate group, p < 0.00001). There was no significant difference in incidence of infections between groups. We observed a significantly longer time to occurrence of infection in the citrate group (20 days vs. 14 days, HR 2.8, 95% CI 1.04-7.6, p = 0.04). By multivariate analysis, age and citrate group were the only independent factors that influenced catheter life span.

CONCLUSIONS

This study shows for the first time that citrate lock reduced catheter complications and increased catheter life span as compared to saline lock in critically ill adults requiring hemodialysis.

Emergence of gentamicin-resistant bacteremia in hemodialysis patients receiving gentamicin lock catheter prophylaxis

BACKGROUND AND OBJECTIVES

Antibiotic locks in catheter-dependent chronic hemodialysis patients reduce the rate of catheter-related blood stream infections (CRIs), but there are no data regarding the long-term consequences of this practice.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Over a 4-year period, from October 1, 2002, to September 30, 2006, we initiated a gentamicin and heparin lock (GHL) protocol in 1410 chronic hemodialysis patients receiving dialysis through a tunneled catheter in eight outpatient units.

RESULTS

Within the first year of the GHL protocol, our CRI rate decreased from 17 to 0.83 events per 1000 catheter-days. Beginning 6 months after initiation of the GHL protocol, febrile episodes occurred in 13 patients with coagulase-negative Staphylococcus bacteremia resistant to gentamicin. Over the 4 years of GHL use, an additional 10 patients developed 11 episodes of gentamicin-resistant CRI (including 7 with Enterococcus faecalis), in which there were 4 deaths, 2 cases of septic shock requiring intensive care unit admission, and 4 cases of endocarditis. Because of these events, the GHL protocol was discontinued at the end of 2006.

CONCLUSIONS

Although the use of GHL effectively lowered the CRI rate in our dialysis population, gentamicin-resistant CRIs emerged within 6 months. Gentamicin-resistant infections are a serious complication of the long-term use of GHLs. Alternative nonantibiotic catheter locks may be preferable to decrease the incidence of CRIs without inducing resistant pathogens.

Epidemiology, surveillance, and prevention of bloodstream infections in hemodialysis patients

Infections cause significant morbidity and mortality in patients undergoing hemodialysis. Bloodstream infections (BSIs) are particularly problematic, accounting for a substantial number of hospitalizations in these patients. Hospitalizations for BSI and other vascular access infections appear to have increased dramatically in hemodialysis patients since 1993. These infections frequently are related to central venous catheter (CVC) use for dialysis access. Regional initiatives that have shown successful decreases in catheter-related BSIs in hospitalized patients have generated interest in replicating this success in outpatient hemodialysis populations. Several interventions have been effective in preventing BSIs in the hemodialysis setting. Avoiding the use of CVCs in favor of access types with lower associated BSI risk is among the most important. When CVCs are used, adherence to evidence-based catheter insertion and maintenance practices can positively influence BSI rates. In addition, facility-level surveillance to detect BSIs and stimulate examination of vascular access use and care practices is essential to a comprehensive approach to prevention. This article describes the current epidemiology of BSIs in hemodialysis patients and effective prevention strategies to decrease the incidence of these devastating infections.

Systematic review of antimicrobials for the prevention of haemodialysis catheter-related infections

BACKGROUND

Almost 30% of chronic haemodialysis (HD) patients are dependent on central venous catheters (CVCs) for their vascular access, and catheter-related bacteraemia (CRB) is the major reason for catheter loss and has been associated with substantial morbidity, including meta-static infections. This systematic review evaluates the benefits and harms of antimicrobial interventions for the prevention of catheter-related infections (CRIs).

METHODS

MEDLINE (1950-May 2009), EMBASE (1980-May 2009) CENTRAL (up to May 2009) and bibliographies of retrieved articles were searched for relevant RCTs. Analysis was by a random effects model and results expressed as rate ratio, relative risk (RR) and weighted mean difference (WMD) with 95% confidence intervals (CI).

RESULTS

A total of 29 trials with 2886 patients and 3005 catheters were included. Antimicrobial catheter locks (AMLs) significantly reduced the rates of CRBs (rate ratio, 0.33, 95% CI 0.24-0.45) and exit-site infections (ESIs) (rate ratio 0.67, 95% CI 0.47-0.96). Exit-site antimicrobial application also significantly reduced the rates of CRBs (rate ratio 0.21, 95% CI 0.12-0.36) and ESIs (rate ratio 0.22, 95% CI 0.10-0.47). Antimicrobial coating of HD catheters and the use of peri-operative antimicrobials did not result in significant reduction in rates of CRBs and ESIs.

CONCLUSION

The use of AMLs and exit-site antimicrobials are useful measures in the reduction of CRIs, whereas antimicrobial impregnated catheters and peri-operative systemic antimicrobial administration have not been found to be beneficial. Further head-to-head trials of various AMLs and exit-site antimicrobials are needed to know about their comparative clinical efficacy.

Sodium citrate versus heparin catheter locks for cuffed central venous catheters: a single-center randomized controlled trial

BACKGROUND

Sodium citrate has antibacterial and anticoagulant properties that are confined to the catheter when used as a catheter lock. Studies of its use as a catheter lock have suggested its efficacy in preventing infection and bleeding complications compared with sodium heparin.

STUDY DESIGN

Open-label randomized controlled trial of 2 catheter locks to examine the hypothesis that sodium citrate catheter locks will reduce catheter-related bacteremia and exit-site infection.

SETTINGS & PARTICIPANTS

232 consenting long-term hemodialysis patients in 4 satellite dialysis units to a large dialysis program with protocolized treatment and targets. All patients were using twin-catheter single-lumen Tesio-Caths (MedComp, Harleysville, PA).

INTERVENTION

6 months' use of 46.7% sodium citrate (citrate) or 5% heparin (heparin) locked postdialysis in the dead space of the central venous catheter.

OUTCOMES & MEASUREMENTS

Primary end point of catheter-related bacteremia and exit-site infection. Secondary end points of catheter thrombosis defined by the use of urokinase lock and infusion, new catheter insertion, catheter-related admission, blood transfusions, parenteral iron, and erythropoietin requirements.

RESULTS

Catheter-related bacteremia did not differ in the 2 groups, with an incidence of 0.7 events/1,000 catheter-days. There was no significant difference in rates of exit-site infection (0.7 versus 0.5 events/1,000 catheter-days; P = 0.5). The secondary end point of catheter thrombosis defined by the use of a urokinase lock was significantly more common in the citrate group, with an incidence of 8 versus 4.3/1,000 catheter-days (P < 0.001). Other secondary end points did not differ. Citrate treatment was curtailed compared with heparin because of a greater incidence of adverse events, with a mean treatment duration before withdrawal of 4.8 +/- 2.0 versus 5.7 +/- 1.2 months, respectively (P < 0.001).

LIMITATIONS

Low baseline catheter-related bacteremia and exit-site infection event rates may have underpowered this study. High adverse-event rates may have been related to high-concentration citrate that led to increased overspill and reduction in lock volume. This may also explain the increased rates of thrombosis in this group.

CONCLUSION

Widespread and long-term use of 46.7% citrate catheter locks with Tesio-Cath access is not justified by this study.

Effect of a solution containing citrate/Methylene Blue/parabens on Staphylococcus aureus bacteria and biofilm, and comparison with various heparin solutions

OBJECTIVES

Some antibiotic solutions increase bacterial resistance and may cause toxic side effects. Heparin, frequently used as an anticoagulant in catheter lock solutions, may cause bleeding and stimulate biofilm formation. The aim of this study was to investigate the effect of a new antibacterial/antithrombotic solution, citrate/Methylene Blue/parabens (C/MB/P), versus various heparin solutions on the viability and the structure of preformed mature biofilms of Staphylococcus aureus bacteria. The degree of eradication of both planktonic and sessile microorganisms was evaluated.

METHODS

The changes in the structure of biofilms after exposure to C/MB/P and several concentrations of heparin were analysed by means of confocal laser scanning microscopy. COMSTAT image analysis was utilized to compare biofilm biomass, average and maximum height, surface coverage and roughness coefficient. Viability studies were performed on both biofilms and supernatant solutions.

RESULTS

C/MB/P, in contrast to heparin solutions, significantly reduced biofilm biomass and thickness and reduced viability by 5 log when compared with saline treatment. No viable planktonic bacteria were detected and the few remaining biofilm cells appeared to be lysed. In contrast, most heparin solutions only reduced viability up to 1.0 log and failed to eradicate planktonic bacteria.

CONCLUSIONS

C/MB/P has a rapid bactericidal effect on the preformed, mature biofilm of S. aureus. The structural changes of biofilms treated with C/MB/P, together with the observed log reduction of viable biofilm cells, confirmed the high potential of this solution to eliminate sessile bacteria. Furthermore, the tested solution entirely eliminated planktonic bacteria detached from the biofilm.

Microbial inactivation properties of a new antimicrobial/antithrombotic catheter lock solution (citrate/methylene blue/parabens)

Background. Microbial infections are the most serious complications associated with indwelling central venous catheters. A catheter lock solution that is both antibacterial and antithrombotic is needed. The goal of this study was to determine whether a new catheter lock solution containing citrate, methylene blue and parabens has antimicrobial properties against planktonic bacteria and against sessile bacteria within a biofilm. These effects were compared to the antimicrobial properties of heparin at 2500 units/ml.

Methods. The tested solution (C/MB/P comprising 7% sodium citrate, 0.05% methylene blue and 0.165% parabens) and individual components were challenged against gram-positive and gram-negative organisms and fungi. Control solutions were heparin with preservatives. Studies included evaluation of eradication of planktonic bacteria and sessile organisms in a biofilm grown on polymeric and glass coupons. Biofilm samples were inspected by scanning electron microscopy, atomic force microscopy and vital stains.

Results. The C/MB/P solution, contrary to heparin, kills most tested planktonic microorganisms within 1 h of incubation. All tested organisms have an MIC of 25% or less of the original concentration of a new catheter lock. Bacteria strains did not develop resistance over more than 40 passages of culture suspensions. The C/MB/P solution is able to kill nearly all sessile bacteria in biofilm growth on plastic or glass discs in 1 h. Microscopic methods demonstrated extensive physical elimination of biofilm deposits from treated coupons. In contrast, heparin had a minimal effect on planktonic or biofilm organisms.

Conclusions. The new multicomponent lock solution has strong antimicrobial properties against both planktonic and sessile microorganisms. By comparison, heparin with preservative has weak antibacterial properties against planktonic and biofilm bacteria. The tested catheter lock may have usefulness in preventing bacterial colonization of haemodialysis catheters and diminishing the incidence of catheter-related bacteraemia.

Antimicrobial lock solutions for the prevention of infections associated with intravascular catheters in patients undergoing hemodialysis: systematic review and meta-analysis of randomized, controlled trials

BACKGROUND

Prevention of catheter-related bloodstream infections in patients undergoing hemodialysis by use of antimicrobial catheter lock solutions has been examined in several trials, but no consensus is available for clinical practice.

METHODS

A systematic review and meta-analysis were performed of randomized controlled trials that compared single or combination antimicrobial catheter lock solutions with heparin or another antimicrobial for the prevention of infections in patients undergoing hemodialysis. The primary outcomes assessed were bloodstream infections, catheter-related bloodstream infections, and the need for catheter removal. Relative risks with 95% confidence intervals (CIs) for individual trials were pooled.

RESULTS

Eleven trials (924 patients) that assessed antibiotic catheter lock solutions and 5 trials (661 patients)that assessed non antibiotic antimicrobial catheter lock solutions met inclusion criteria. None of the trials assessed all bloodstream infections. Antibiotic catheter lock solutions significantly reduced catheter-related bloodstream infections (relative risk, 0.44; 95% CI, 0.38-0.50). Significant heterogeneity for this outcome could be explained by smaller effect estimates in larger trials that reported adequate randomization methods (relative risk, 0.60; 95%CI, 0.54-0.67). Efficacy was higher when additional preventive measures were used and to prevent the first episode of catheter-related bloodstream infection. Catheter removal rates were significantly reduced (relative risk, 0.35;95% CI, 0.23-0.55). Resistance development was documented in a single patient. Data concerning nonantibiotic antimicrobial lock solutions were limited and heterogeneous. High-quality trials that used additional preventive measures showed a significant reduction in catheter-related bloodstream infections (relative risk, 0.25; 95% CI,0.13-0.50).

CONCLUSIONS

Antibiotic catheter lock solutions reduce catheter-related bloodstream infections, with a number needed to treat of 4 patients (95% CI, 4-5), and catheter removal rates in patients undergoing hemodialysis. The use of antibiotic catheter lock solutions should be considered in routine clinical practice in conjunction with other prevention modalities.

The life-threatening hemodialysis catheter heparin lock caused bleeding in a child after peritoneal catheter removal

Hemodialysis catheter patency is regularly maintained by high-concentration heparin filling, according to manufacturer's recommendation. Surprisingly, there are only few reports on serious bleeding complications in children on dialysis. A case of serious, life-threatening hemorrhage in a child after tunneled peritoneal catheter removal because of hemodialysis catheter heparin lock flushing is described. Discussion of the literature data is presented. Further investigations are needed to develop the guidelines for pediatric dialysis catheter care, including the optimal concentration for heparin lock as the possible heparin alternatives, but until that moment, previously suggested guidelines to prevent hemorrhagic complications in dialyzed children should be emphasized.

Prevention of catheter lumen occlusion with rT-PA versus heparin (Pre-CLOT): study protocol of a randomized trial [ISRCTN35253449]

Background

Many patients with end-stage renal disease use a central venous catheter for hemodialysis access. A large majority of these catheters malfunction within one year of insertion, with up to two-thirds due to thrombosis. The optimal solution for locking the catheter between hemodialysis sessions, to decrease the risk of thrombosis and catheter malfunction, is unknown. The Prevention of Catheter Lumen Occlusion with rt-PA versus Heparin (PreCLOT) study will determine if use of weekly rt-PA, compared to regular heparin, as a catheter locking solution, will decrease the risk of catheter malfunction.

Methods/Design

The study population will consist of patients requiring chronic hemodialysis thrice weekly who are dialyzed with a newly inserted permanent dual-lumen central venous catheter. Patients randomized to the treatment arm will receive rt-PA 1 mg per lumen once per week, with heparin 5,000 units per ml as a catheter locking solution for the remaining two sessions. Patients randomized to the control arm will receive heparin 5,000 units per ml as a catheter locking solution after each dialysis session. The study treatment period will be six months, with 340 patients to be recruited from 14 sites across Canada. The primary outcome will be catheter malfunction, based on mean blood flow parameters while on hemodialysis, with a secondary outcome of catheter-related bacteremia. A cost-effectiveness analysis will be undertaken to assess the cost of maintaining a catheter using rt-PA as a locking solution, compared to the use of heparin.

Discussion

Results from this study will determine if use of weekly rt-PA, compared to heparin, will decrease catheter malfunction, as well as assess the cost-effectiveness of these locking solutions.

A Prospective, Randomized, Double-Blind Crossover Study on the Use of 5% Citrate Lock versus 10% Citrate Lock in Permanent Hemodialysis Catheters

Central venous catheters are used as permanent vascular access for chronic hemodialysis when construction of an arteriovenous fistula is not possible or contraindicated. We prospectively evaluated the efficacy and safety of a 5% citrate versus 10% citrate catheter lock for permanent single-lumen dialysis catheters in a double-blind, crossover study of 28 patients during 1,876 dialysis sessions. There was a slightly higher number of dialysis sessions with clot formation in the 5% citrate group; entirely attributable to the formation of small clots. There was no statistically significant difference in the formation of large clots, complete obstruction of the catheter or the need for urokinase between the 2 study groups. In view of the ongoing debate on the safety of high-concentration citrate catheter locks, we conclude that a 5% citrate lock is equally efficient in preventing catheter dysfunction compared with a 10% citrate lock and is therefore the preferred citrate catheter-locking solution.