Randomized, double-blind trial of an antibiotic-lock technique for prevention of gram-positive central venous catheter-related infection in neutropenic patients with cancer

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.

Prophylactic antibiotics for preventing gram-positive infections associated with long-term central venous catheters in adults and children receiving treatment for cancer

BACKGROUND

This is an updated version of a Cochrane Review last published in 2013. Long-term central venous catheters (CVCs), including tunnelled CVCs (TCVCs) and totally implanted devices or ports (TIDs), are increasingly used when treating people with cancer. Despite international guidelines on sterile insertion and appropriate CVC maintenance and use, infections remain a common complication. These infections are mainly caused by gram-positive bacteria. Antimicrobial prevention strategies aimed at these micro-organisms could potentially decrease the majority of CVC-related infections. The aim of this review was to evaluate the efficacy of prophylactic antibiotics for the prevention of gram-positive infections in people with cancer who have long-term CVCs.

OBJECTIVES

To assess the effects of administering antibiotics prior to the insertion of long-term CVCs or as a flush/lock solution, or both during long-term CVC access to prevent gram-positive CVC-related infections in adults and children receiving treatment for cancer.

SEARCH METHODS

The search for this updated review was conducted on 19 November 2020. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE via Ovid and Embase via Ovid. We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform portal for additional articles.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared either the administration of prophylactic antibiotics prior to long-term CVC insertion versus no administration of antibiotics, or the use of an antibiotic versus a non-antibiotic flush/lock solution in long-term CVCs, in adults and children receiving treatment for cancer.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Two authors independently selected studies, classified them and extracted data onto a predesigned data collection form. The outcomes of interest were gram-positive catheter-related infection events and total number of CVCs and CVC days. We pooled the data using a random-effects model for meta-analyses. We used the GRADE approach to assess the certainty of the evidence.  MAIN RESULTS: For this update, we identified 310 potentially relevant studies and screened them for eligibility. We included one additional RCT with 404 participants. The original review included 11 RCTs with a total of 840 people with cancer (adults and children). In total this review included 12 RCTs with 1244 participants. Antibiotics prior to insertion of the CVC Six trials compared the use of antibiotics (vancomycin, teicoplanin, ceftazidime or cefazolin) versus no antibiotics given before the insertion of a long-term CVC. One study did not observe any CVC-related infection events in either group was not included in the quantitative analysis as it was not possible to calculate a risk ratio. Administering an antibiotic prior to insertion of the CVC may not reduce gram-positive CVC-related infections (pooled risk ratio 0.67, confidence interval (CI) 95% 0.32 to 1.43; control versus intervention group risk 10.4% versus 7.3% of the participants; 5 studies, 648 participants; moderate-certainty evidence). We sought adverse event data, but these were not described by the authors. The overall risk of bias was deemed low.   Antibiotics as a flushing or locking solution Six trials compared a combined antibiotic (vancomycin, amikacin or taurolidine) and heparin solution with a heparin-only solution for flushing or locking the long-term CVC after use. One study did not observe any CRS events and was not include this study in the quantitative analysis as it was not possible to calculate a risk ratio. Flushing and locking long-term CVCs with a combined antibiotic and heparin solution likely reduced the risk of gram-positive CVC-related infections compared to a heparin-only solution (pooled rate ratio 0.47, CI 95% 0.26 to 0.85; control versus intervention group rate ratio 0.66 versus 0.27 per 1000 CVC-days; 5 studies, 443 participants; moderate-certainty evidence). One trial reported a higher incidence of occlusions and participants in one trial reported an unpleasant taste after flushing associated with a combined antibiotic and heparin solution. The overall risk of bias was deemed low.  AUTHORS' CONCLUSIONS: Since the last version of this review, we included one additional study. There was no observed benefit of administering antibiotics before the insertion of long-term CVCs to prevent gram-positive CVC-related infections. Flushing or locking long-term CVCs with an antibiotic solution likely reduces gram-positive CVC-related infections experienced in people at risk of neutropenia through chemotherapy or disease. However, a limitation of this review is heterogeneity between the studies for both outcomes. Insufficient data were available to evaluate if the conclusions apply equally for different CVC types and for adults versus children. It must be noted that the use of an antibiotic flush/lock solution may increase microbial antibiotic resistance, therefore it should be reserved for high-risk people or if the baseline CVC-related infection rates are high. Further research is needed to identify high-risk groups most likely to benefit from these antibiotic flush/lock solutions.

Comparative analysis of infectious complications with outpatient vs. inpatient care for adults with high-risk myeloid neoplasm receiving intensive induction chemotherapy

We recently reported an early hospital discharge (EHD) care strategy following intensive acute myeloid leukemia (AML)-like chemotherapy is safe. To evaluate its impact on infectious outcomes, we compared all adults treated from 8/1/2014 to 7/31/2018 discharging within 72 h of completing chemotherapy (EHD) with hospitalized patients (controls) across 354 induction and 259 post-remission cycles. While overall outcomes were similar, gram-positive bacteremias were more common in EHD patients than control (p<.001), although they received fewer days of IV antimicrobials (p< .001). Notably, cumulative infection risks in EHD patients were similar after induction and post-remission therapy. In multivariable analysis, only EHD status was independently associated with risk for gram-positive bacteremia (p= .01), whereas the only independent risk factor for fungal infection was fluconazole (vs. posaconazole) use (p< .001). The observation of increased rates of gram-positive bacteremias with EHD identifies improvements in catheter management as one area to further increase the safety of this care approach.

Impact of chest subcutaneous fat on the occurrence of central venous port-related infectious complications in cancer patients

Purpose

There is no concrete evidence to support the association between the amount of subcutaneous fat area (SFA) in the central venous port-insertion site (precordium) and port-related complications. We aimed to investigate the relationship between SFA in the midclavicular line and postoperative infectious complications in patients undergoing port-insertion surgery.

Methods

This was a single-institute and historical cohort study of 174 patients who underwent first central venous port implantation surgery for chemotherapy between January 2014 and December 2018. SFA in the midclavicular line was measured using preoperative computed tomography scans. The patients were divided into three groups according to SFA amount tertiles, and we investigated the association of SFA with infectious and all-cause complication events within 1 year.

Results

Within a median follow-up of 306 days, the patients with intermediate SFA had significantly higher infection-free survival than those with low and high SFA (low vs. intermediate vs. high: 80.4% vs. 97.7% vs. 83.4%, respectively, p=0.034). In contrast, there was no significant difference in the overall complication-free survival among the groups (low vs. intermediate vs. high: 80.4% vs. 88.9% vs. 81.8%, respectively, p=0.29). Low SFA was independently associated with high risk of infectious complications (hazard ratio, 9.45; 95% confidence interval, 1.07–83.22, p=0.043).

Conclusion

Low SFA in the midclavicular line was an independent risk factor for infectious complications in the chemotherapy setting. This practical indicator can be useful for optimizing patients’ nutritional status and when considering other types of vascular access to support administration of intravenous chemotherapy.

Catheter-related blood stream infections: prevalence, risk factors and antimicrobial resistance pattern

Background

Intravascular devices have significant potential for producing iatrogenic diseases resulting in catheter-related blood stream infections (CRBSIs). A study was undertaken to find the prevalence of CRBSI among patients in acute wards and to analyze the associated risk factors, causative pathogens with their antibiotic susceptibility (ABST) patterns.

Methods

Randomly ten days per month were chosen, for a period of two years. All the acute wards patients who were on indwelling blood catheters were identified. Those fulfilling the CRBSI criteria were further worked up for confirmation of diagnosis by differential time to positivity. The catheter tip was cultured by Maki's semiquantitative method. ABST of the isolates obtained was performed by Kirby-Bauer disk diffusion method.

Results

The prevalence of CRBSI was found to be 39.25% with the most common organism isolate being Serratia marcescens (23.81%). The immunocompromised status of the patients and catheterisation time were significant risk factors. Methicillin resistance was found to be 33.33% in coagulase-negative staphylococci. The resistance to vancomycin among the Entercoccus faecium isolates was found to be 33.33%. Among the gram negatives, resistance to aminoglycosides, fluoroquinolones and third-generation cephalosporins was high.

Conclusion

The study highlights the importance of regular surveillance programs, an efficient infection control program, strict adherence to antiseptic measures and use of a rational antibiotic policy for the early diagnosis and better management of CRBSI.

Central venous catheter-related infections in hematology and oncology: 2020 updated guidelines on diagnosis, management, and prevention by the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO)

Cancer patients frequently require central venous catheters for therapy and parenteral nutrition and are at high risk of central venous catheter-related infections (CRIs). Moreover, CRIs prolong hospitalization, cause an excess in resource utilization and treatment cost, often delay anti-cancer treatment, and are associated with a significant increase in mortality in cancer patients. We therefore summoned a panel of experts by the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO) and updated our previous guideline on CRIs in cancer patients. After conducting systematic literature searches on PubMed, Medline, and Cochrane databases, video- and meeting-based consensus discussions were held. In the presented guideline, we summarize recommendations on definition, diagnosis, management, and prevention of CRIs in cancer patients including the grading of strength of recommendations and the respective levels of evidence. This guideline supports clinicians and researchers alike in the evidence-based decision-making in the management of CRIs in cancer patients.

A Randomized, Double-Blind, Placebo-Controlled Trial (TAURCAT Study) of Citrate Lock Solution for Prevention of Endoluminal Central Venous Catheter Infection in Neutropenic Hematological Patients

Infection of long-term central venous catheters (CVCs) remains a challenge in the clinical management of cancer patients. We aimed to determine whether a lock solution with taurolidine-citrate-heparin would be more effective than placebo for preventing nontunneled CVC infection in high-risk neutropenic hematologic patients. We performed a prospective, multicenter, randomized (1:1), double-blind, parallel, superiority, placebo-controlled trial involving 150 hematological patients with neutropenia carrying nontunneled CVCs who were assigned to receive CVC lock solution with taurolidine-citrate-heparin or heparin alone. The primary endpoint was bacterial colonization of the CVC hubs. Secondary endpoints were the incidence of catheter-related bloodstream infection (CRBSI), CVC removal, adverse events related to the lock solution, and the 30-day case fatality rate. CVC lock solution with taurolidine-citrate-heparin was associated with less colonization of the CVC hubs than that with placebo, with no statistically significant differences: 4.1%, versus 10.1% (relative risk [RR] = 0.41, 95% confidence interval [CI] = 0.11 to 1.52), with a cumulative incidence of 4.17 (95% CI = 0.87 to 11.70) and 10.14 (95% CI = 4.18 to 19.79), respectively. There were no significant differences regarding the secondary endpoints. Only three episodes of CRBSI occurred during the study period. No adverse events related to the administration of the lock solution occurred. In this trial involving high-risk patients carrying nontunneled CVCs, the use of taurolidine-citrate-heparin did not show a benefit over the use of placebo. Nevertheless, the safety of this prevention strategy and the trend toward less hub colonization in the taurolidine-citrate-heparin group raise the interest in assessing its efficacy in centers with higher rates of CRBSI. (This study has been registered in ISRCTN under identifier ISRCTN47102251.).

Indian Society of Critical Care Medicine Position Statement for Central Venous Catheterization and Management 2020

Background and Purpose

Short-term central venous catheterization (CVC) is one of the commonly used invasive interventions in ICU and other patient-care areas. Practice and management of CVC is not standardized, varies widely, and need appropriate guidance. Purpose of this document is to provide a comprehensive, evidence-based and up-to-date, one document source for practice and management of central venous catheterization. These recommendations are intended to be used by critical care physicians and allied professionals involved in care of patients with central venous lines.

Methods

This position statement for central venous catheterization is framed by expert committee members under the aegis of Indian Society of Critical Care Medicine (ISCCM). Experts group exchanged and reviewed the relevant literature. During the final meeting of the experts held at the ISCCM Head Office, a consensus on all the topics was made and the recommendations for final document draft were prepared. The final document was reviewed and accepted by all expert committee members and after a process of peer-review this document is finally accepted as an official ISCCM position paper.

Modified grade system was utilized to classify the quality of evidence and the strength of recommendations. The draft document thus formulated was reviewed by all committee members; further comments and suggestions were incorporated after discussion, and a final document was prepared.

Results

This document makes recommendations about various aspects of resource preparation, infection control, prevention of mechanical complication and surveillance related to short-term central venous catheterization. This document also provides four appendices for ready reference and use at institutional level.

Conclusion

In this document, committee is able to make 54 different recommendations for various aspects of care, out of which 40 are strong and 14 weak recommendations. Among all of them, 42 recommendations are backed by any level of evidence, however due to paucity of data on 12 clinical questions, a consensus was reached by working committee and practice recommendations given on these topics are based on vast clinical experience of the members of this committee, which makes a useful practice point. Committee recognizes the fact that in event of new emerging evidences this document will require update, and that shall be provided in due time.

Abbreviations list

ABHR: Alcohol-based hand rub; AICD: Automated implantable cardioverter defibrillator; BSI: Blood stream infection; C/SS: CHG/silver sulfadiazine; Cath Lab: Catheterization laboratory (Cardiac Cath Lab); CDC: Centers for Disease Control and Prevention; CFU: Colony forming unit; CHG: Chlorhexidine gluconate; CL: Central line; COMBUX: Comparison of Bedside Ultrasound with Chest X-ray (COMBUX study); CQI: Continuous quality improvement; CRBSI: Catheter-related blood stream infection; CUS: Chest ultrasonography; CVC: Central Venous Catheter; CXR: Chest X-ray; DTTP: Differential time to positivity; DVT: Deep venous thrombosis; ECG: Electrocardiography; ELVIS: Ethanol lock and risk of hemodialysis catheter infection in critically ill patients; ER: Emergency room; FDA: Food and Drug Administration; FV: Femoral vein; GWE: Guidewire exchange; HD catheter: Hemodialysis catheter; HTS: Hypertonic saline; ICP: Intracranial pressure; ICU: Intensive Care Unit; IDSA: Infectious Disease Society of America; IJV: Internal jugular vein; IPC: Indian penal code; IRR: Incidence rate ratio; ISCCM: Indian Society of Critical Care Medicine; IV: Intravenous; LCBI: Laboratory confirmed blood stream infection; M/R: Minocycline/rifampicin; MBI-LCBI: Mucosal barrier injury laboratory-confirmed bloodstream infection; MRSA: Methicillin-resistant Staphylococcus aureus; NHS: National Health Service (UK); NHSN: National Healthcare Safety Network (USA); OT: Operation Theater; PICC: Peripherally-inserted central catheter; PIV: Peripheral intravenous line; PL: Peripheral line; PVI: Povidone-iodine; RA: Right atrium; RCT: Randomized controlled trial; RR: Relative risk; SCV/SV: Subclavian vein; ScVO₂: Central venous oxygen saturation; Sn: Sensitivity; SOP: Standard operating procedure; SVC: Superior vena cava; TEE: Transesophageal echocardiography; UPP: Useful Practice Points; USG: Ultrasonography; WHO: World Health Organization

How to cite this article

Javeri Y, Jagathkar G, Dixit S, Chaudhary D, Zirpe KG, Mehta Y, et al. Indian Society of Critical Care Medicine Position Statement for Central Venous Catheterization and Management 2020. Indian J Crit Care Med 2020;24(Suppl 1):S6–S30.

Prevalence of and risk factors for intravenous catheter infection in hospitalized cattle, goats, and sheep

BACKGROUND

Intravenous catheter (IVC) use in hospitalized ruminants is a common procedure. Limited information is available describing complications associated with IVCs.

HYPOTHESES

Prevalence of IVC infections in hospitalized ruminants is >50%. Intravenous catheters maintained for >5 days are more likely to be infected than those maintained for <5 days. Intravenous catheters placed non-aseptically have a higher risk for infection than those placed aseptically.

ANIMALS

Thirty-four cattle, 39 goats, and 33 sheep were hospitalized in a university teaching hospital.

METHODS

Prospective observational study. The IVCs from cattle, goats, and sheep admitted for medical and surgical procedures were randomly selected and submitted for bacteriological culture and susceptibility testing.

RESULTS

Prevalence values (95% confidence interval) of infected catheters were 61.8 (45.5, 78.1), 51.3 (35.3, 66.7), and 42.4% (25.2, 58.8) in cattle, goats, and sheep, respectively. Coagulase-negative Staphylococcus spp was the most frequently isolated bacterium. Catheter type/placement technique was a significant (P = .03) predictor of IVC infection in goats but not in cattle (P = .65) and sheep (P = .47). Antibiotic use and reason for catheter placement were not significant predictors of IVC infection in all species. Catheters maintained for >4 days had a higher likelihood of being infected than those maintained for <4 days in all species.

CONCLUSIONS AND CLINICAL IMPORTANCE

Clinicians should consider replacing catheters maintained for >4 days to reduce IVC infection.

Validity of surrogate endpoints assessing central venous catheter-related infection: evidence from individual- and study-level analyses

OBJECTIVES

The prevention of catheter-related bloodstream infection (CRBSI) has been an area of intense research, but the heterogeneity of endpoints used to define catheter infection makes the interpretation of randomized controlled trials (RCTs) problematic. The aim of this study was to determine the validity of different endpoints for central venous catheter infections.

DATA SOURCES

(a) Individual-catheter data were collected from 9428 catheters from four large RCTs; (b) study-level data from 70 RCTs were identified with a systematic search. Eligible studies were RCTs published between January 1987 and October 2018 investigating various interventions to reduce infections from short-term central venous catheters or short-term dialysis catheters. For each RCT the prevalence rates of CRBSI, quantitative catheter tip colonization, catheter-associated infection (CAI) and central line-associated bloodstream infection (CLABSI) were extracted for each randomized study arm.

METHODS

CRBSI was used as the gold-standard endpoint, for which colonization, CAI and CLABSI were evaluated as surrogate endpoints. Surrogate validity was assessed as (1) the individual partial coefficient of determination (individual-pR²) using individual catheter data; (2) the coefficient of determination (study-R²) from mixed-effect models regressing the therapeutic effect size of the surrogates on the effect size of CRBSI, using study-level data.

RESULTS

Colonization showed poor agreement with CRBSI at the individual-patient level (pR² = 0.33 95% CI 0.28-0.38) and poor capture at the study level (R² = 0.42, 95% CI 0.21-0.58). CAI showed good agreement with CRBSI at the individual-patient level (pR² = 0.80, 95% CI 0.76-0.83) and moderate capture at the study level (R² = 0.71, 95% CI 0.51-0.85). CLABSI showed poor agreement with CRBSI at the individual patient level (pR² = 0.34, 95% CI 0.23-0.46) and poor capture at the study level (R² = 0.28, 95% CI 0.07-0.76).

CONCLUSIONS

CAI is a moderate to good surrogate endpoint for CRBSI. Colonization and CLABSI do not reliably reflect treatment effects on CRBSI and are consequently more suitable for surveillance than for clinical effectiveness research.

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.

Administration of taurolidine-citrate lock solution for prevention of central venous catheter infection in adult neutropenic haematological patients: a randomised, double-blinded, placebo-controlled trial (TAURCAT)

Background

Catheter-related bloodstream infection (CRBSI) is one of the most frequent complications in patients with cancer who have central venous catheters (CVCs) implanted and is associated with substantial morbidity and mortality. Taurolidine is a non-antibiotic agent with broad-spectrum antimicrobial activity, which has been used as a lock solution to prevent CRBSI in some settings. However, little is known about its usefulness in high-risk adult neutropenic patients with cancer. This prospective randomised clinical trial aims to test the hypothesis that taurolidine-citrate lock solution is more effective than placebo for preventing catheter infection in neutropenic haematological patients.

Methods

This study is a prospective, multicentre, randomised, double-blinded, parallel, superiority, placebo-controlled trial. Patients with haematological cancer who are expected to develop prolonged neutropenia (> 7 days) and who have a non-tunnelled CVC implanted will be randomised to receive prophylactic taurolidine-citrate-heparin solution using a lock technique (study group) or heparin alone (placebo group). The primary endpoint will be bacterial colonisation of the CVC hubs. The secondary endpoints will be the incidence of CRBSI, CVC removal, adverse events, and 30-day case-fatality rate.

Discussion

The lock technique is a preventive strategy that inhibits bacterial colonisation in the catheter hubs, which is the initial step of endoluminal catheter colonisation and the development of infection. Taurolidine is a nontoxic agent that does not develop antibiotic resistance because it acts as an antiseptic rather than an antibiotic. Taurolidine has shown controversial results in the few trials conducted in cancer patients. These studies have important limitations due to the lack of data on adult and/or high-risk neutropenic patients, the type of catheters studied (tunnelled or ports), and the lack of information regarding the intervention (e.g. dwelling of the solution, time, and periodicity of the lock technique). If our hypothesis is proven, the study could provide important solid evidence on the potential usefulness of this preventive procedure in a population at high risk of CRBSI, in whom this complication may significantly impair patient outcome.

Trial registration

ISRCTN, ISRCTN47102251. Registered on 9 September 2015.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2647-y) contains supplementary material, which is available to authorized users.

Intravascular Catheters and Biofilm Control

Intravascular catheters are the most common cause of nosocomially acquired bloodstream infections. Bacteria found adhering to the intraluminal surfaces of catheters are the principal source and cause of these infections. Adherent bacteria overtime are known to form multicellular communities which become encased within a three dimensional matrix of extracellular polymeric material known as biofilms, which are thought to be responsible for persistent infections. Consequently, a number of technologies have been developed to help prevent and control biofilms in intravascular catheters. One such approach involves impregnating catheter material with antimicrobial agents. Unfortunately these methods are not universally effective in preventing catheter-related biofilm infections. Technologies that utilise antimicrobials, as catheter locks have been shown to have more potential for preventing biofilm formation and reducing the incidences of catheter related bloodstream infections (CRBSI). This article discusses the significance of biofilms in intravascular catheters and determines whether the treatments available today are proving to be effective for controlling biofilms and draws attention to future avenues which are being investigated to control biofilms and therefore CRBSI.

Incidence of Sepsis in Central Venous Catheter-Bearing Patients with Hematologic Malignancies: Preliminary Results

Background

Indwelling central venous catheters (CVCs) are essential devices in the management of patients with hematological disorders treated with chemotherapy. However, their nature predisposes patients to unwanted complications.

Methods

CVC-related complications were retrospectively analyzed in 227 hematologic patients who were consecutively admitted to our hematology department between May 2002 and April 2004. Patients’ diagnoses comprised acute myeloid leukemia (36.8%), acute lymphoid leukemia (7.3%), lymphoproliferative disorders (28.3%), multiple myeloma (19.5%), myeloproliferative syndromes (5%) and others (3.1%). The CVCs used were polyurethane three lumen 7-Fr (111 patients) for chemotherapy and 12-Fr (114 patients) for chemotherapy and peripheral blood stem cell apheresis, plus two tunneled catheters.

Results

The pathological events were: bacteriaemias (n=46); occlusions (n=10); exit tunnel infections (n=8); thrombosis (n=6); lung emboli (n=2). Among febrile patients the bacteriemia frequency was 20%, of which 13.6% were CVC-related (with a higher incidence in leukemia patients (p=0.027). Among the isolates, gram-positive bacteria were found in 29 cases (23 CVC-related cases), and gram-negative bacteria in 16 cases (8 CVC-related cases). Only one patient had Candida albicans sepsis. At univariate and multivariate analysis significant risk factors for infection (p<0.0001) were only the number of days/catheters and neutropenia duration.

Conclusions

In our hematologic patients, the CVC complications were mainly septic, with only 10.1% of CVC-related bacteriemias, despite prolonged catheterization duration. Acute leukemia patients were at major risk for sepsis, probably due to a more severe neutropenia and prolonged catheterization duration.

Tetrasodium EDTA as a Novel Central Venous Catheter Lock Solution Against Biofilm

Background:

Central venous catheter (CVC)-related bloodstream infections (BSIs) are known to increase rates of morbidity and mortality in both inpatients and outpatients, including hematology-oncology patients and those undergoing hemodialysis or home infusion therapy. Biofilm-associated organisms on the lumens of these catheters have reduced susceptibility to antimicrobial chemotherapy. This study tested the efficacy of tetrasodium EDTA as a catheter lock solution on biofilms of several clinically relevant microorganisms.

Methods:

Biofilms ofStaphylococcus epidermidis, methicillin-resistantS. aureus, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, andCandida albicanswere grown to levels of approximately 1 × 105colony-forming units (CFU)/cm−1on CVC segments in a model system, then subjected to the tetrasodium EDTA lock treatment.

Results:

Comparisons of biofilms before and after exposure to the 40-mg/mL−1tetrasodium EDTA lock for 21 hours showed that the biofilm viable cell counts of all organisms tested were significantly reduced (P< .05) after exposure to the treatment.

Conclusion:

Antimicrobial lock treatment using 40 mg/mL−1of tetrasodium EDTA for at least 21 hours could significantly reduce or potentially eradicate CVC-associated bio-films of clinically relevant microorganisms (Infect Control Hosp Epidemiol2005;26:515-519).

Strategies to Prevent Central Line-Associated Bloodstream Infections in Acute Care Hospitals: 2014 Update

Previously published guidelines are available that provide comprehensive recommendations for detecting and preventing healthcare-associated infections (HAIs). The intent of this document is to highlight practical recommendations in a concise format designed to assist acute care hospitals in implementing and prioritizing their central line-associated bloodstream infection (CLABSI) prevention efforts. This document updates “Strategies to Prevent Central Line-Associated Bloodstream Infections in Acute Care Hospitals,” published in 2008. This expert guidance document is sponsored by the Society for Healthcare Epidemiology of America (SHEA) and is the product of a collaborative effort led by SHEA, the Infectious Diseases Society of America (IDSA), the American Hospital Association (AHA), the Association for Professionals in Infection Control and Epidemiology (APIC), and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise. The list of endorsing and supporting organizations is presented in the introduction to the 2014 updates.

Bloodstream infections in patients with solid tumors

Little information is currently available regarding bloodstream infection (BSI) in patients with solid tumors who, for a variety of reasons, are particularly predisposed to develop this condition. In this review we focus on the incidence, epidemiology, clinical features, etiology, antimicrobial resistance, and outcomes of BSI of adult cancer patients with solid tumors. Most episodes of BSI occur in non-neutropenic patients, in whom the site of primary or metastatic tumor often serves as the portal of entry. The urinary tract and the abdomen are the most frequent sources of infection, and cholangitis is the most common recurrent source of BSI. Gram-negative bacilli are becoming the leading cause of BSI in patients with solid tumors, and the rate of multidrug resistance is increasingly being recognized. The case-fatality rate in patients with solid tumors and BSI is high, especially among those with comorbidities, advanced neoplasms, corticosteroid therapy, and shock at presentation.

Bacterial adherence and biofilm formation on medical implants: a review

Biofilms are a complex group of microbial cells that adhere to the exopolysaccharide matrix present on the surface of medical devices. Biofilm-associated infections in the medical devices pose a serious problem to the public health and adversely affect the function of the device. Medical implants used in oral and orthopedic surgery are fabricated using alloys such as stainless steel and titanium. The biological behavior, such as osseointegration and its antibacterial activity, essentially depends on both the chemical composition and the morphology of the surface of the device. Surface treatment of medical implants by various physical and chemical techniques are attempted in order to improve their surface properties so as to facilitate bio-integration and prevent bacterial adhesion. The potential source of infection of the surrounding tissue and antimicrobial strategies are from bacteria adherent to or in a biofilm on the implant which should prevent both biofilm formation and tissue colonization. This article provides an overview of bacterial biofilm formation and methods adopted for the inhibition of bacterial adhesion on medical implants.

Incidence and risk factors for central venous access port-related infection in Chinese cancer patients

BACKGROUND/PURPOSE

Cytotoxic chemotherapy via central venous access ports is an important part of the standard treatment for most cancers, but it is accompanied with the risk of infections. This study aimed to analyze the incidence and risk factors for central venous access port-related infection (CPI) among Chinese patients receiving cytotoxic chemotherapy.

METHODS

Between January 1, 2002 and December 31, 2005 a total of 1391 cancer patients with 1449 totally implantable central venous access ports were evaluated. The log-rank test and Cox proportional hazards model were used for the analyses of risk factors.

RESULTS

The overall CPI incidence rate was 0.21 per 1000 catheter-days. Hematological malignancies and head and neck cancer were associated with an increased risk of CPI (hazard ratio 4.00 and 4.11, respectively, both p < 0.001) and less infection-free catheter longevity (p < 0.001) compared with other cancer types. Chemotherapy in an adjuvant setting was associated with a lower risk of infection than for patients in a nonadjuvant setting (p < 0.001). The most common pathogens isolated from CPI were Pseudomonas aeruginosa and Candida.

CONCLUSION

Infection remains to be a challenging issue for totally implantable central venous ports. Implementation of an insertion bundle for the prevention of central line-associated bloodstream infections is warranted, especially for those patients with hematological and head and neck cancers, as well as for patients receiving chemotherapy in the metastatic settings.

Strategies to Prevent Central Line-Associated Bloodstream Infections in Acute Care Hospitals: 2014 Update

Previously published guidelines are available that provide comprehensive recommendations for detecting and preventing healthcare-associated infections (HAIs). The intent of this document is to highlight practical recommendations in a concise format designed to assist acute care hospitals in implementing and prioritizing their central line-associated bloodstream infection (CLABSI) prevention efforts. This document updates “Strategies to Prevent Central Line-Associated Bloodstream Infections in Acute Care Hospitals,” published in 2008. This expert guidance document is sponsored by the Society for Healthcare Epidemiology of America (SHEA) and is the product of a collaborative effort led by SHEA, the Infectious Diseases Society of America (IDSA), the American Hospital Association (AHA), the Association for Professionals in Infection Control and Epidemiology (APIC), and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise. The list of endorsing and supporting organizations is presented in the introduction to the 2014 updates.

Cohort Study of the Pathogenesis and Molecular Epidemiology of Catheter-Related Bloodstream Infection in Neonates With Peripherally Inserted Central Venous Catheters

Objective.

To better define the pathogenesis of catheter-related bloodstream infection (BSI) in neonates with peripherally inserted central venous catheters (PICCs) to guide the development of more effective strategies for prevention.

Design.

Prospective nested cohort study.

Setting.

Level III neonatal intensive care unit in a community hospital.

Methods.

During a randomized trial to assess the safety and efficacy of a prophylactic vancomycin-heparin catheter-lock solution for the prevention of catheter-related BSI in neonates with PICCs, we performed cultures of peripheral and catheter-drawn blood samples, and quantitative cultures of catheter hub samples if BSI was suspected clinically. We performed semiquantitative cultures of the catheter tip and the catheter hub and the skin at the insertion site when the catheter was removed. Molecular subtyping by pulsed-field electrophoresis was used to determine the probable pathogenesis of all BSIs due to coagulase-negative staphylococci (CoNS); for BSIs caused by other microorganisms, epidemiologic concordance was based on speciation and antibiograms. Catheter-related BSI was considered extraluminally acquired if concordance was demonstrable solely between isolates recovered from the catheter tip and the blood, independent of concordance with isolates recovered from the insertion site. Catheter-related BSI was considered intraluminally acquired if concordance was demonstrated only between isolates recovered from the catheter hub and the blood. The source of the infection was considered indeterminate if both concordance patterns were present.

Results.

Nosocomial BSI was identified in 23 of the 82 neonates in the cohort. Fifteen of these infections, 14 of which were caused by CoNS, were considered definite or probable catheter-related BSIs. Catheter-related BSI was intraluminally acquired in 10 (67%) of 15 patients, extraluminally acquired in 3 (20%), and indeterminate in 2 (13%).

Conclusions.

Most catheter-related BSIs in neonates with PICCs are caused by CoNS and derive from intraluminal contamination. Strategies for prevention of catheter-related BSI directed at this predominant mechanism of infection are most likely to be effective.

Guidelines for the Prevention of Intravascular Catheter–Related Infections

Background:

Although many catheter-related blood-stream infections (CRBSIs) are preventable, measures to reduce these infections are not uniformly implemented.

Objective:

To update an existing evidenced-based guideline that promotes strategies to prevent CRBSIs.

Data Sources:

The MEDLINE database, conference proceedings, and bibliographies of review articles and book chapters were searched for relevant articles.

Studies Included:

Laboratory-based studies, controlled clinical trials, prospective interventional trials, and epidemiologic investigations.

Outcome Measures:

Reduction in CRBSI, catheter colonization, or catheter-related infection.

Synthesis:

The recommended preventive strategies with the strongest supportive evidence are education and training of healthcare providers who insert and maintain catheters; maximal sterile barrier precautions during central venous catheter insertion; use of a 2% chlorhexidine preparation for skin antisepsis; no routine replacement of central venous catheters for prevention of infection; and use of antiseptic/antibiotic-impregnated short-term central venous catheters if the rate of infection is high despite adherence to other strategies (ie, education and training, maximal sterile barrier precautions, and 2% chlorhexidine for skin antisepsis).

Conclusion:

Successful implementation of these evidence-based interventions can reduce the risk for serious catheter-related infection.

Risk Factors for Central Line–Associated Bloodstream Infection in Pediatric Intensive Care Units

Objective.

We sought to identify risk factors for central line-associated bloodstream infection (CLABSI) to describe children who might benefit from adjunctive interventions.

Design.

Case-control study of children admitted to the medical-surgical intensive care unit (ICU) or cardiac ICU from January 1, 2004, through December 31, 2007.

Setting.

Children's Hospital Boston is a freestanding, 396-bed quaternary care pediatric hospital with a 29-bed medical-surgical ICU and a 24-bed cardiac ICU.

Patients.

Case patients were patients with CLABSI who were identified by means of prospective surveillance. Control subjects were patients with a central venous catheter who were matched by ICU admission date.

Methods.

Multivariate conditional logistic regression models were used to identify independent risk factors for CLABSI and to derive and to validate a prediction rule.

Results.

Two hundred three case patients were matched with 406 control subjects. Independent predictors of CLABSI included duration of ICU central access (odds ratio [OR] for 15 or more days, 18.41 [95% confidence interval {CI} 4.10-82.56]; P < .001), central venous catheter placement in the ICU (OR for 2 or more ICU-placed catheters, 8.63 [95% CI, 2.63-28.38]; P = .001), nonoperative cardiovascular disease (OR, 7.44 [95% CI, 2.13-25.98]; P = .012), presence of gastrostomy tube (OR, 3.48 [95% CI, 1.55-7.79]; P = .003), receipt of parenteral nutrition (OR, 3.12 [95% CI, 1.55-6.32]; P= .002), and receipt of blood transfusion (OR, 2.55 [95% CI, 1.21-5.36]; P = .014). By use of risk factors known before central venous catheter placement, our model predicted CLABSI with a positive predictive value of 54% and a negative predictive value of 79%.

Conclusions.

Duration of central access, receipt of parenteral nutrition, and receipt of blood transfusion were confirmed as risk factors for CLABSI among children in the ICU. Newly identified risk factors include presence of gastrostomy tube, nonoperative cardiovascular disease, and ICU placement of central venous catheter. Children with these risk factors may be candidates for adjunctive interventions for CLABSI prevention.

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.

Stability and compatibility of antimicrobial lock solutions

PURPOSE

Published stability and compatibility data on a growing array of solutions used for antimicrobial lock therapy (ALT) are reviewed.

SUMMARY

ALT involves the instillation of a highly concentrated antimicrobial, often in combination with an anticoagulant, into a central venous catheter (CVC) lumen; this technique is often used for prophylaxis after CVC insertion or as an adjunctive treatment in cases of central line-associated bloodstream infection (CLABSI) if catheter removal is not feasible. Optimal selection of stable and compatible antimicrobials and additives can maximize catheter dwell times, streamline pharmacy compounding practices, and help ensure patient safety. Of 98 articles on ALT solutions identified in a literature search, 17 met the prespecified criteria for the use of validated stability and compatibility methodology. Antimicrobials active against common CLABSI pathogens that may be appropriate for ALT include cefazolin, cefotaxime, ceftazidime, ciprofloxacin, daptomycin, gentamicin, linezolid, telavancin, ticarcillin-clavulanic acid, and vancomycin; validated data demonstrate the stability of these agents in solution with heparin or nonheparin anticoagulants over 72-96 hours or longer. Other antifungal agents and antiinfectives (e.g., ethyl alcohol) have been used in specific patients and ALT situations. The prolonged stability of several antimicrobial-additive combinations may allow for extended dwell times and less frequent lock solution exchanges.

CONCLUSION

Pharmacists' knowledge of diverse combinations of antimicrobial agents and additives in lock solutions, including several shown to be stable and compatible for extended periods, can help expand and optimize the use of ALT in both treatment and prophylactic modalities.

Prevention of catheter infection using a biodegradable tissue adhesive composed of human serum albumin and disuccinimidyl tartrate

A new material was prepared to reduce catheter infection composed of a flocked silicone sheet (AmTiO2NP-F) with TiO2 nanoparticle–immobilized poly(ethylene terephthalate) fibers modified with surface amino groups. This system was used in conjunction with a tissue adhesive composed of disuccinimidyl tartrate and human serum albumin. At a fixed disuccinimidyl tartrate content of 0.2 mmol in human serum albumin solution, AmTiO2NP-F bonded well with collagen-based casing (a model material for skin), with bond strength increasing to a maximum of 38 w/v% human serum albumin. The adhesive bonded AmTiO2NP-F to subcutaneous tissue in mice, and infiltration of the tissue into the AmTiO2NP-F further increased the bond strength for long-term insertions. The material was degraded within 7 days of implantation, and tissue reaction was mild, while infection was completely prevented. These results indicate that the combined use of AmTiO2NP-F and disuccinimidyl tartrate-A for implanted catheters can significantly alleviate the associated risk of infection.

Comparison of different doses of vancomycin andteicoplanin lock solutions in catheters colonized with Staphylococcus epidermidis: An in vitro, blinded, antibiotic lock study

BACKGROUND

The antibiotic lock (AL) technique is used for sterilization ofthe intraluminal surface of catheters. This technique consists of filling a catheter lumen with an antibiotic solution and allowing it to dwell for a time sufficient to sterilize the device. Glycopeptide antibiotics (vancomycin and teicoplanin) are commonly used agents for this purpose. But studies evaluating the different dosages of these antibiotics, their optimum concentrations, and duration in AL treatment are lacking.

OBJECTIVE

The aim of this study was to compare the efficacy of differentdoses of vancomycin/saline solution (VSS) and teicoplanin/saline solution (TSS) and to establish the optimal dosage and time needed to eliminate intraluminal methicillin-resistant Staphylococcus epidermidis colonization.

METHODS

This in vitro AL study was conducted at the Department of Infectious Diseases and Clinical Microbiology, Adnan Menderes University Medical Faculty, Aydin, Turkey. Catheters were divided into 2 groups those colonized with slime-forming S epidermidis, and those colonized with non-slime-forming S epidermidis. In each group, catheters were locked with VSS or TSS at 1-, 3-, and 5-mg/mL doses. Catheters instilled with saline solution were used as the control group. After 12 hours of incubation, the catheters were drained and filled with human plasma. Instillation of human plasma or AL solution was alternated every 12 hours to simulate clinical conditions. Every other day, catheters locked with each antibiotic dose or saline were cultured to determine colony count. These procedures were maintained until the catheters were sterile.

RESULTS

The baseline counts of slime-forming and non-slime-forming S epidermidisadhered to 1-cm segment catheters were 39 × 106 and 32 × 106 colony-forming units, respectively. The bacterial count was decreased significantly from baseline on the first day after the start of treatment (day 1) (P < 0.001). At the end of day 7, all catheters treated with antibiotics were sterile. The de creases in bacterial count were statistically similar in catheters treated with all doses of VSS and TSS. Also, the decrease in intraluminal colonization was statistically similar in catheters colonized with slime-forming S epidermidis and non-slime-forming S epidermidis.

CONCLUSION

In this in vitro, blinded AL study, the efficacy of vancomycin and teicoplanin lock solutions were similar and sterilized the catheters in 7 days, suggesting that the 2 antibiotics might be selected for shorter durations compared with those currently recommended for AL treatment in catheter-related infections due to methicillin-resistant staphylococci.

Bacterial biofilms: a diagnostic and therapeutic challenge

Bacteria have traditionally been regarded as individual organisms growing in homogeneous planktonic populations. However, bacteria in natural environments usually form communities of surface-adherent organisms embedded in an extracellular matrix, called biofilms. Current antimicrobial strategies often fail to control bacteria in the biofilm mode of growth. Treatment failure is particularly frequent in association with intracorporeal or transcutaneous medical devices and compromised host immunity. The rising prevalence of these risk factors over the last decades has paralleled the increase in biofilm infections. This review discusses the shortcomings of current therapies against biofilms both in theory and with clinical examples. Biofilm characteristics are described with a focus on new diagnostic and therapeutic targets.

Central venous catheter-related infections in hematology and oncology: 2012 updated guidelines on diagnosis, management and prevention by the Infectious Diseases Working Party of the German Society of Hematology and Medical Oncology

BACKGROUND

Cancer patients are at increased risk for central venous catheter-related infections (CRIs). Thus, a comprehensive, practical and evidence-based guideline on CRI in patients with malignancies is warranted.

PATIENTS AND METHODS

A panel of experts by the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO) has developed a guideline on CRI in cancer patients. Literature searches of the PubMed, Medline and Cochrane databases were carried out and consensus discussions were held.

RESULTS

Recommendations on diagnosis, management and prevention of CRI in cancer patients are made, and the strength of the recommendation and the level of evidence are presented.

CONCLUSION

This guideline is an evidence-based approach to the diagnosis, management and prevention of CRI in cancer patients.

Prophylactic antibiotics for preventing Gram positive infections associated with long-term central venous catheters in oncology patients

BACKGROUND

This is an updated version of the review which was first published in the Cochrane Database of Systematic Reviews in 2006. Long-term central venous catheters (CVCs), including tunnelled CVCs (TCVCs) and totally implanted devices or ports (TIDs), are increasingly used when treating oncology patients. Despite international guidelines on sterile insertion and appropriate CVC maintenance and use, infection remains a common complication. These infections are mainly caused by Gram positive bacteria. Antimicrobial prevention strategies aimed at these micro-organisms could potentially decrease the majority of CVC infections. The aim of this review was to evaluate the efficacy of antibiotics in the prevention of Gram positive infections in long-term CVCs.

OBJECTIVES

To determine the efficacy of administering antibiotics prior to the insertion of long-term CVCs, or flushing or locking long-term CVCs with a combined antibiotic and heparin solution, or both, to prevent Gram positive catheter-related infections in adults and children receiving treatment for cancer.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (to June 2013) and the MEDLINE and EMBASE databases (1966 to 2013).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing prophylactic antibiotics given prior to long-term CVC insertion with no antibiotics, RCTs comparing a combined antibiotic and heparin solution with a heparin-only solution to flush or lock newly inserted long-term CVCs, and RCTs comparing a combination of these interventions in adults and children receiving treatment for cancer.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies, classified them and extracted data on to a pre-designed data collection form. We pooled data using the RevMan software version 5.2 and used random-effects (RE) model methods for meta-analyses.

MAIN RESULTS

We included 11 trials with a total of 828 oncology patients (adults and children). We assessed most included studies to be at a low or unclear risk of bias. Five trials compared the use of antibiotics (vancomycin, teicoplanin or ceftazidime) given before the insertion of the long-term CVC with no antibiotics, and six trials compared antibiotics (vancomycin, amikacin or taurolidine) and heparin with a heparin-only solution for flushing or locking the long-term CVC after use. Administering an antibiotic prior to insertion of the CVC did not significantly reduce Gram positive catheter-related sepsis (CRS) (five trials, 360 adults; risk ratio (RR) 0.72, 95% confidence interval (CI) 0.33 to 1.58; I² = 5 2%; P = 0.41).Flushing and locking long-term CVCs with a combined antibiotic and heparin solution significantly reduced the risk of Gram positive catheter-related sepsis compared with a heparin-only solution (468 participants, mostly children; RR 0.47, 95% CI 0.28 to 0.80; I² = 0%; P = 0.005). For a baseline infection rate of 15%, this reduction translated into a number needed to treat (NNT) of 12 (95% CI 9 to 33) to prevent one catheter-related infection. We considered this evidence to be of a moderate quality.

AUTHORS' CONCLUSIONS

There was no benefit to administering antibiotics before the insertion of long-term CVCs to prevent Gram positive catheter-related infections. Flushing or locking long-term CVCs with a combined antibiotic and heparin solution appeared to reduce Gram positive catheter-related sepsis experienced in people at risk of neutropenia through chemotherapy or disease. Due to insufficient data it was not clear whether this applied equally to TCVCs and totally implanted devices (TIDs), or equally to adults and children. The use of a combined antibiotic and heparin solution may increase microbial antibiotic resistance, therefore it should be reserved for high risk people or where baseline CVC infection rates are high (> 15%). Further research is needed to identify high risk groups most likely to benefit.

Effects of bacteriocins on methicillin-resistant Staphylococcus aureus biofilm

Control of biofilms formed by microbial pathogens is an important subject for medical researchers, since the development of biofilms on foreign-body surfaces often causes biofilm-associated infections in patients with indwelling medical devices. The present study examined the effects of different kinds of bacteriocins, which are ribosomally synthesized antimicrobial peptides produced by certain bacteria, on biofilms formed by a clinical isolate of methicillin-resistant Staphylococcus aureus (MRSA). The activities and modes of action of three bacteriocins with different structures (nisin A, lacticin Q, and nukacin ISK-1) were evaluated. Vancomycin, a glycopeptide antibiotic used in the treatment of MRSA infections, showed bactericidal activity against planktonic cells but not against biofilm cells. Among the tested bacteriocins, nisin A showed the highest bactericidal activity against both planktonic cells and biofilm cells. Lacticin Q also showed bactericidal activity against both planktonic cells and biofilm cells, but its activity against biofilm cells was significantly lower than that of nisin A. Nukacin ISK-1 showed bacteriostatic activity against planktonic cells and did not show bactericidal activity against biofilm cells. Mode-of-action studies indicated that pore formation leading to ATP efflux is important for the bactericidal activity against biofilm cells. Our results suggest that bacteriocins that form stable pores on biofilm cells are highly potent for the treatment of MRSA biofilm infections.

Central venous catheter care for the patient with cancer: American Society of Clinical Oncology clinical practice guideline

PURPOSE

To develop an evidence-based guideline on central venous catheter (CVC) care for patients with cancer that addresses catheter type, insertion site, and placement as well as prophylaxis and management of both catheter-related infection and thrombosis.

METHODS

A systematic search of MEDLINE and the Cochrane Library (1980 to July 2012) identified relevant articles published in English.

RESULTS

The overall quality of the randomized controlled trial evidence was rated as good. There is consistency among meta-analyses and guidelines compiled by other groups as well.

RECOMMENDATIONS

There is insufficient evidence to recommend one CVC type or insertion site; femoral catheterization should be avoided. CVC should be placed by well-trained providers, and the use of a CVC clinical care bundle is recommended. The use of antimicrobial/antiseptic-impregnated and/or heparin-impregnated CVCs is recommended to decrease the risk of catheter-related infections for short-term CVCs, particularly in high-risk groups; more research is needed. The prophylactic use of systemic antibiotics is not recommended before insertion. Data are not sufficient to recommend for or against routine use of antibiotic flush/lock therapy; more research is needed. Before starting antibiotic therapy, cultures should be obtained. Some life-threatening infections require immediate catheter removal, but most can be treated with antimicrobial therapy while the CVC remains in place. Routine flushing with saline is recommended. Prophylactic use of warfarin or low-molecular weight heparin is not recommended, although a tissue plasminogen activator (t-PA) is recommended to restore patency to occluded catheters. CVC removal is recommended when the catheter is no longer needed or if there is a radiologically confirmed thrombosis that worsens despite anticoagulation therapy.

Full and broad-spectrum in vivo eradication of catheter-associated biofilms using gentamicin-EDTA antibiotic lock therapy

Biofilms that develop on indwelling devices are a major concern in clinical settings. While removal of colonized devices remains the most frequent strategy for avoiding device-related complications, antibiotic lock therapy constitutes an adjunct therapy for catheter-related infection. However, currently used antibiotic lock solutions are not fully effective against biofilms, thus warranting a search for new antibiotic locks. Metal-binding chelators have emerged as potential adjuvants due to their dual anticoagulant/antibiofilm activities, but studies investigating their efficiency were mainly in vitro or else focused on their effects in prevention of infection. To assess the ability of such chelators to eradicate mature biofilms, we used an in vivo model of a totally implantable venous access port inserted in rats and colonized by either Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, or Pseudomonas aeruginosa. We demonstrate that use of tetrasodium EDTA (30 mg/ml) as a supplement to the gentamicin (5 mg/ml) antibiotic lock solution associated with systemic antibiotics completely eradicated Gram-positive and Gram-negative bacterial biofilms developed in totally implantable venous access ports. Gentamicin-EDTA lock was able to eliminate biofilms with a single instillation, thus reducing length of treatment. Moreover, we show that this combination was effective for immunosuppressed rats. Lastly, we demonstrate that a gentamicin-EDTA lock is able to eradicate the biofilm formed by a gentamicin-resistant strain of methicillin-resistant S. aureus. This in vivo study demonstrates the potential of EDTA as an efficient antibiotic adjuvant to eradicate catheter-associated biofilms of major bacterial pathogens and thus provides a promising new lock solution.

Central venous port-related infection in patients with malignant tumors: an observational study

PURPOSE

We evaluated the characteristics of central venous port (CVP)-related infection with microbiological assessments in patients with malignant tumors.

MATERIALS AND METHODS

In a prospective setting, patients with CVP for the treatment of malignant tumors were enrolled in this study. The incidence of CVP-related infection during three months was determined. Microbiological surveillance from skin swab was performed before and after CVP placement.

RESULTS

Fifty-nine patients were enrolled in this study, and 60 CVPs were implanted. Thirty-six (61%) patients had head and neck malignancies. Access route was subclavian vein in 43 (71.7%) CVPs and forearm vein in 17 (28.3%). CVP-related infection was observed in three (5.1%) patients: port-pocket infection in one and probable CVP-related infection in two patients, respectively. No definitive CVP-related bloodstream infection was observed. Before the placement of CVP, colonization at the insertion site was observed in ten subclavian CVP patients, while no colonization was observed in the forearm CVP patients. At 1 and 4 weeks, detection rates of colonization were also higher in subclavian CVP patients. No definitive relationship was demonstrated between skin colonization and clinical development of CVP-related infection.

CONCLUSION

The rate of CVP-related infection in this prospective evaluation in patients with malignant tumors was comparable to previous studies. Colonization of the skin was more prominent in the subclavian site than in the forearm site. Although skin colonization was not proven to be a risk factor of infection, these results may draw attention to the adequate maintenance of CVP. (

TRIAL REGISTRATION

UMIN000003664).

Catheter-related infections in pediatric patients with cancer

Central venous catheters (CVCs) are essential in the management of pediatric patients receiving antineoplastic therapy or bone marrow transplants, and have significantly improved their quality of life, but CVC-related infectious complications are a major source of morbidity. It has been estimated that 14-51 % of the CVCs implanted in children with malignancies may be complicated by bacteremia, and that the incidence of infections is 1.4-1.9 episodes per 1,000 CVC days. However, there are few recent data concerning the epidemiology of CVC-related infections, the prevalence of antimicrobial resistance in their etiology, or the main factors associated with an increased risk of infection by type of catheter, patient age, the type of cancer, or the presence of neutropenia. Moreover, although various new strategies have been proposed in an attempt to reduce the risk of CVC-related infections, such as catheters impregnated with antiseptics/antibiotics, lock antibiotic prophylaxis, the use of ointments at the exit site, and antithrombotic prophylaxis, their real efficacy in children has not yet been demonstrated. The management of CVC-related infections remains difficult, mainly because of the number of still open questions (including the choice of optimal antimicrobial therapy because of the increasing isolation of multiresistant bacterial strains, treatment duration, whether catheters should be removed or not, the feasibility of guidewire exchange, and the usefulness of antibiotic lock therapy) and the lack of studies of children with cancer. Only well-designed, prospective clinical trials involving pediatric cancer patients can clarify optimal prevention and treatment strategies for CVC-related infections in this population.

A guide to antibiotics for the interventional radiologist

Antibiotics are among the most common pharmaceutical agents used by the interventional radiologist. This article updates some of the practical aspects of the use of antibiotics in interventional radiological practice and provides some general guidelines with respect to indications for and selection of antibiotics. In particular, the objectives of this article are to review the basic pharmacology of the common antibiotic agents, the interventional radiological procedures in which prophylactic antibiotics are usually administered, the specific antimicrobial agents recommended for prophylaxis before common interventional radiological procedures, the appropriate antibiotics for patients allergic to penicillins, and the indications for antibiotic prophylaxis to prevent bacterial endocarditis.

Central line-associated bloodstream infections: prevention and management

Approximately 80,000 central venous line-associated bloodstream infections (CLA-BSI) occur in the United States each year. CLA-BSI is most commonly caused by coagulase-negative staphylococci, Staphylococcus aureus, Candida spp, and aerobic gram-negative bacilli. These organisms commonly gain entrance in into the bloodstream via the catheter-skin interface (insertion site) or via the catheter hub. Use of strict aseptic technique for insertion is the key method for the prevention of CLA-BSI. Various methods can be used to reduce unacceptably high rates of CLA-BSI, including use of an antiseptic- or antibiotic-impregnated catheter, daily chlorhexidine baths/washes, and placement of a chlorhexidine-impregnated sponge over the insertion site.

Successful prevention of tunneled, central catheter infection by antibiotic lock therapy using cefotaxime

BACKGROUND

Chronic hemodialysis patients frequently require vascular access through central venous catheters (CVCs). The most significant complication of these catheters is infection. This risk can be lowered by the use of an antibiotic-Heparin lock. This study focuses on hemodialysis patients using Tunneled-cuffed catheters (TCC), to assess the rate of catheter-related infections (CRI) in catheter-restricted filling with Cefotaxime and Heparin in end stage renal disease patients.

METHODS

A double-blind randomized study was conducted to compare 5000 U/ml Heparin plus10 mg/ml cefotaxime (CE/HS) as catheter-lock solutions, with Heparin (5000 U/ml) alone. A total of 30 patients with end-stage renal disease and different etiologies, were enrolled for chronic hemodialysis with permanent catheters from December 2009 to March 2010. These patients were randomly assigned to two groups of 15 members. Blood samples were collected for culture, sensitivity, and colony count, from the catheter lumen and the peripheral vein. CRI was considered as the end point.

RESULTS

The rate of CRI was significantly lower in the cefotaxime group versus control group (p < 0.001). No exit site infection was occurred in both groups. Infection-free survival rates at 180 days were 100% for the CE/HS group, and 56% for the HS group.

CONCLUSIONS

Antibiotic lock therapy using cefotaxime reduces the risk of CRI in hemodialysis patients.

Inhibition of bacterial adhesion on medical devices

Microbial infections resulting from bacterial adhesion to biomaterial surfaces have been observed on almost all medical devices. Biofilm infections pose a number of clinical challenges due to their resistance to immune defence mechanisms and antimicrobials, and, regardless of the sophistication of the implant, all medical devices are susceptible to microbial colonisation and infection. Research efforts are currently directed towards eliminating or reducing infection of medical devices. Strategies to prevent biofilm formation include physiochemical modification of the biomaterial surface to create anti-adhesive surfaces, incorporation of antimicrobial agents into medical device polymers, mechanical design alternatives, and release of antibiotics. Nevertheless, the success of these alternatives has been modest, mainly due to the various environments into which devices are placed and the diversity of ways in which organisms can colonise surfaces. Biosurfactants have been reported as a promising strategy as they effectively inhibit bacterial adhesion and retard biofilm formation, and are thus potentially useful as a new generation of anti-adhesive and antimicrobial coatings for medical devices.

Clinical outcome of catheter salvage in neutropenic cancer patients with catheter-related infection

BACKGROUND

Catheter-related infections (CRI) cause significant morbidity and mortality in cancer patients, particularly during episodes of chemotherapy-induced neutropenia. This study was performed to evaluate clinical features and outcomes of CRI in neutropenic cancer patients.

METHODS

We retrospectively analyzed clinical characteristics and outcome of febrile neutropenic cancer patients with CRI who visited the emergency department from January 1996 to June 2007.

RESULTS

A total of 51 neutropenic cancer patients with CRI were identified and 53 organisms were isolated from culture specimens. The mean ± standard deviation patient age was 50 ± 15 y and the most common underlying disease was lymphoma (n = 27, 53%). Gram-positive organisms accounted for 77% of all isolated pathogens (41/53). Initial catheter salvage was attempted in 38 episodes of CRI, of which 20 were successful. In the current study the overall success rate of catheter salvage attempts was 52.6%. The failure rate of catheter salvage was significantly higher in CRI caused by Gram-negative pathogens than by Gram-positive pathogens.

CONCLUSION

Although catheter salvage should be cautiously attempted for cancer patients with CRI, it might not be a treatment option for neutropenic cancer patients with CRI caused by Gram-negative bacteria.

Physical compatibility of 4% sodium citrate with selected antimicrobial agents

PURPOSE

The physical compatibility of 4% sodium citrate with vancomycin, gentamicin, tobramycin, daptomycin, and linezolid was evaluated.

METHODS

Admixtures were prepared by mixing 4% sodium citrate with clinically relevant concentrations of antimicrobial agents (vancomycin 5 mg/mL, vancomycin 10 mg/mL, vancomycin 20 mg/mL, daptomycin 5 mg/mL, gentamicin 2.4 mg/mL, tobramycin 2.4 mg/mL, and linezolid 1 mg/mL). Three samples of each admixture were incubated (1) at 22-23 degrees C and exposed to light, (2) in a water bath at 37 degrees C and exposed to light, (3) at 22-23 degrees C and protected from light, and (4) in a water bath at 37 degrees C and protected from light. Visual compatibility, spectrophotometric absorbance, and pH were evaluated immediately after mixing (baseline) and at 8, 24, and 48 hours. Physical compatibility was defined as the absence of visible precipitation, a pH value at 48 hours that did not vary by more than 10% from baseline, and an absorbance value of <0.015.

RESULTS

There was no visual evidence of precipitation and no clinically important changes in pH observed during the 48-hour study period in any admixture. However, turbidity, based on absorbance, was noted with vancomycin 20 mg/mL at each time point.

CONCLUSION

No evidence of incompatibility was observed when vancomycin 5 mg/ mL, vancomycin 10 mg/mL, daptomycin 5 mg/mL, gentamicin 2.4 mg/mL, tobramycin 2.4 mg/mL, or linezolid 1 mg/mL was mixed with 4% sodium citrate as might occur in an antimicrobial lock. Vancomycin 20 mg/mL mixed with 4% sodium citrate displayed spectrophotometric evidence of incompatibility.