Guidelines for the management of intravascular catheter-related infections

Distribution of virulence genes in bacteremic methicillin-resistant Staphylococcus aureus isolates from various sources

BACKGROUND/PURPOSE

Methicillin-resistant Staphylococcus aureus (MRSA) can encode proteins which directly bind bacteria to many tissues and medical devices or catheters to trigger pathogenesis. However, the relationship between genetic backgrounds and virulent factors in MRSA isolates remained incompletely understood yet.

METHODS

MRSA isolates were collected from blood cultures of patients with infective endocarditis, bone/joint infection, skin/soft tissue infection, or catheter-related bacteremia in hemodialysis at a tertiary medical center between 2005 and 2011. MRSA isolates were characterized by the methods of spa, multilocus sequence, and staphylococcal cassette chromosome mec (SCCmec) typing. Identification of virulence gene expression was measured by Power SYBR Green PCR Master Mix.

RESULTS

Overall collected were 136 MRSA bacteremic isolates, including those from the cases of infective endocarditis (n = 23), bone/joint infection (n = 49), skin/soft tissue infection (n = 20), or catheter-related bacteremia in patients with acute kidney injury or end-stage renal stage receiving hemodialysis (n = 54). CC8-ST239-MRSA-SCCmec type III-spa type t037 was the most prevalent type observed in all of 136 MRSA bacteremic isolates. The prevalent genes in the group of infective endocarditis were clfA, clfB, fnbA, ebpS, eap, emp, sae, and eno; bone/joint infections clfA, emp, sae, and eno; skin/soft tissue infection eno; hemodialysis catheter-related bacteremia clfA and sae. The distribution of each gene was not statically different among four groups.

CONCLUSIONS

A major MRSA lineage, CC8-ST239-MRSA-SCCmec type III-spa type t037, is noted among bacteremic MRSA isolates. No disease-specific virulent genes can be identified.

Increased Clinical and Economic Burden Associated With Peripheral Intravenous Catheter-Related Complications: Analysis of a US Hospital Discharge Database

The burden of complications associated with peripheral intravenous use is underevaluated, in part, due to the broad use, inconsistent coding, and lack of mandatory reporting of these devices. This study aimed to analyze the clinical and economic impact of peripheral intravenous-related complications on hospitalized patients. This analysis of Premier Perspective® Database US hospital discharge records included admissions occurring between July 1, 2013 and June 30, 2015 for pneumonia, chronic obstructive pulmonary disease, myocardial infarction, congestive heart failure, chronic kidney disease, diabetes with complications, and major trauma (hip, spinal, cranial fractures). Admissions were assumed to include a peripheral intravenous. Admissions involving surgery, dialysis, or central venous lines were excluded. Multivariable analyses compared inpatient length of stay, cost, admission to intensive care unit, and discharge status of patients with versus without peripheral intravenous-related complications (bloodstream infection, cellulitis, thrombophlebitis, other infection, or extravasation). Models were conducted separately for congestive heart failure, chronic obstructive pulmonary disease, diabetes with complications, and overall (all 7 diagnoses) and adjusted for demographics, comorbidities, and hospital characteristics. We identified 588 375 qualifying admissions: mean (SD), age 66.1 (20.6) years; 52.4% female; and 95.2% urgent/emergent admissions. Overall, 1.76% of patients (n = 10 354) had peripheral intravenous-related complications. In adjusted analyses between patients with versus without peripheral intravenous complications, the mean (95% confidence interval) inpatient length of stay was 5.9 (5.8-6.0) days versus 3.9 (3.9-3.9) days; mean hospitalization cost was $10 895 ($10 738-$11 052) versus $7009 ($6988-$7031). Patients with complications were less likely to be discharged home versus those without (62.4% [58.6%-66.1%] vs 77.6% [74.6%-80.5%]) and were more likely to have died (3.6% [2.9%-4.2%] vs 0.7% [0.6%-0.9%]). Models restricted to single admitting diagnosis were consistent with overall results. Patients with peripheral intravenous-related complications have longer length of stay, higher costs, and greater risk of death than patients without such complications; this is true across diagnosis groups of interest. Future research should focus on reducing these complications to improve clinical and economic outcomes.

Hemodialysis-Associated Infections

Hemodialysis patients are at increased risk of infections, which are common adverse events among this patient population. We review factors contributing to infections among hemodialysis patients and epidemiology of common infections and outbreaks, including bloodstream infections, vascular access infections, and infections caused by bloodborne pathogens. Recommendations for prevention are discussed with emphasis on essential infection control practices for hemodialysis settings.

Chirurgische Infektionen bei Kindern und Jugendlichen

Der menschliche Organismus ist von einer unzähligen Menge von Mikroorganismen umgeben. Dringen diese Krankheitserreger in uns ein, dann laufen Wechselbeziehungen zwischen dem Eindringling und dem Wirtsorganismus ab. Krankheit resultiert, wenn die Mikroorganismen aufgrund ihrer verschiedenen Determinanten der Pathogenität und Virulenz den Wettlauf mit der Infektabwehr des Makroorganismus gewonnen haben. Mit diesem Problem hatten sich Chirurgen zu allen Zeiten auseinanderzusetzen und es hat bis heute nicht an Aktualität verloren.

Yarrowia lipolytica: a beneficious yeast in biotechnology as a rare opportunistic fungal pathogen: a minireview

Yarrowia lipolytica is one of the most studied "non-conventional" yeast species capable of synthesizing a wide group of valuable metabolites, in particular lipases and other hydrolytic enzymes, microbial oil, citric acid, erythritol and γ-decalactone. Processes based on the yeast have GRAS status ("generally recognized as safe") given by Food and Drug Administration. The majority of research communications regarding to Y. lipolytica claim that the yeast species is non-pathogenic. In spite of that, Y. lipolytica, like other fungal species, can cause infections in immunocompromised and critically ill patients. The yeast possess features that facilitate invasion of the host cell (particularly production of hydrolytic enzymes), as well as the protection of the own cells, such as biofilm formation. The aim of this study was to present well-known yeast species Y. lipolytica as a rare opportunistic fungal pathogen. Possible pathogenicity and epidemiology of this yeast species were discussed. Antifungal drugs susceptibility and increasing resistance to azoles in Y. lipolytica yeasts were also presented.

Antibiotic lock therapy for salvage of tunneled central venous catheters with catheter colonization and catheter-related bloodstream infection

Central venous catheters (CVCs) represent a significant source of infection in patients undergoing hematopoietic stem cell transplantation and can add to the cost of care, morbidity, and mortality. Organisms forming biofilms on the inner surface of catheters require a much higher local antibiotic concentration to clear the pathogen growth. Antibiotic lock therapy (ALT) represents one such strategy to achieve such high intraluminal concentrations of antibiotics and can facilitate catheter salvage. Patients with catheter colonization (CC) or hemodynamically stable catheter-related bloodstream infection (CRBSI) received ALT per institutional policy. We analyzed the incidence of CC and CRBSI and salvage rate of tunneled CVCs (Hickman) with ALT in patients undergoing hematopoietic stem cell transplant in this retrospective study. Catheter colonization was noted in 9.8% and CRBSI in 10.7% patients. Gram-negative bacilli (GNB) accounted for 45% and 83% of isolates in CC and CRBSI, respectively. In patients with CRBSI, the rate of catheter salvage with the use of ALT in addition to systemic antibiotics was 86% compared to 55% in patients with systemic antibiotics use only (P = 0.06). There was no CRBSI related mortality, and no increase in resistant strains was noted at subsequent CRBSI. In conclusion, ALT represents an important strategy for catheter salvage, especially for gram-negative infections, in a carefully selected patient population.

A Guide to Utilization of the Microbiology Laboratory for Diagnosis of Infectious Diseases: 2018 Update by the Infectious Diseases Society of America and the American Society for Microbiology

The critical nature of the microbiology laboratory in infectious disease diagnosis calls for a close, positive working relationship between the physician/advanced practice provider and the microbiologists who provide enormous value to the healthcare team. This document, developed by experts in laboratory and adult and pediatric clinical medicine, provides information on which tests are valuable and in which contexts, and on tests that add little or no value for diagnostic decisions. This document presents a system-based approach rather than specimen-based approach, and includes bloodstream and cardiovascular system infections, central nervous system infections, ocular infections, soft tissue infections of the head and neck, upper and lower respiratory infections, infections of the gastrointestinal tract, intra-abdominal infections, bone and joint infections, urinary tract infections, genital infections, and other skin and soft tissue infections; or into etiologic agent groups, including arthropod-borne infections, viral syndromes, and blood and tissue parasite infections. Each section contains introductory concepts, a summary of key points, and detailed tables that list suspected agents; the most reliable tests to order; the samples (and volumes) to collect in order of preference; specimen transport devices, procedures, times, and temperatures; and detailed notes on specific issues regarding the test methods, such as when tests are likely to require a specialized laboratory or have prolonged turnaround times. In addition, the pediatric needs of specimen management are also emphasized. There is intentional redundancy among the tables and sections, as many agents and assay choices overlap. The document is intended to serve as a guidance for physicians in choosing tests that will aid them to quickly and accurately diagnose infectious diseases in their patients.

Comparison of Copper(II)-Ligand Complexes as Mediators for Preparing Electrochemically Modulated Nitric Oxide-Releasing Catheters

Further studies aimed at examining the activity of different Cu(II)-ligand complexes to serve as electron-transfer mediators to prepare novel antimicrobial/thromboresistant nitric oxide (NO)-releasing intravenous catheters are reported. In these devices, the NO release can be modulated by applying different potentials or currents to reduce the Cu(II)-complexes to Cu(I) species which then reduce nitrite ions into NO_(g) within a lumen of the catheter. Four different ligands are compared with respect to NO generation efficiency and stability over time using both single- and dual-lumen silicone rubber catheters: N-propanoate- N, N-bis(2-pyridylethyl)amine (BEPA-Pr), N-propanoate- N, N-bis(2-pyridylmethyl)amine (BMPA-Pr), 1,4,7-trimethyl-1,4,7-triazacyclononane (Me₃TACN), and tris(2-pyridylmethyl)amine (TPMA). Of these, the Cu(II)BEPA-Pr and Cu(II)Me₃TACN complexes provide biomedically useful NO fluxes from the surface of the catheters, >2 × 10^-10 mol·min^-1·cm^-2, under conditions mimicking the bloodstream environment. Cu(II)Me₃TACN exhibits the best stability over time with a steady and continuous NO release observed for 8 d under a nitrogen atmosphere. Antimicrobial experiments conducted over 5 d with NO-releasing catheters turned "on" electrochemically for only 3 or 6 h each day revealed >2 logarithmic units in reduction of bacterial biofilm attached to the catheter surfaces. The use of optimal Cu(II)-ligand complexes within a lumen reservoir along with high levels of nitrite ions can potentially provide an effective method of preventing/decreasing the rate of infections caused by intravascular catheters.

In Vitro and In Vivo Activity of a Novel Catheter Lock Solution against Bacterial and Fungal Biofilms

Central-line-associated bloodstream infections are increasingly recognized to be associated with intraluminal microbial biofilms, and effective measures for the prevention and treatment of bloodstream infections remain lacking. This report evaluates a new commercially developed antimicrobial catheter lock solution (ACL), containing trimethoprim (5 mg/ml), ethanol (25%), and calcium EDTA (Ca-EDTA) (3%), for activity against bacterial and fungal biofilms, using in vitro and in vivo (rabbit) catheter biofilm models. Biofilms were formed by bacterial (seven different species, including vancomycin-resistant Enterococcus [VRE]) or fungal (Candida albicans) species on catheter materials. Biofilm formation was evaluated by quantitative culture (CFU) and scanning electron microscopy (SEM). Treatment with ACL inhibited the growth of adhesion-phase biofilms in vitro after 60 min (VRE) or 15 min (all others), while mature biofilms were completely inhibited after exposure for 2 or 4 h, compared to control. Similar results were observed for drug-resistant bacteria. Compared to the heparinized saline controls, ACL lock therapy significantly reduced the catheter bacterial (3.49 ± 0.75 versus 0.03 ± 0.06 log CFU/catheter; P = 0.016) and fungal (2.48 ± 1.60 versus 0.55 ± 1.19 log CFU/catheter segment; P = 0.013) burdens in the catheterized rabbit model. SEM also demonstrated eradication of bacterial and fungal biofilms in vivo on catheters exposed to ACL, while vigorous biofilms were observed on untreated control catheters. Our results demonstrated that ACL was efficacious against both adhesion-phase and mature biofilms formed by bacteria and fungi in vitro and in vivo.

A totally implantable venous access port associated with bloodstream infection caused by Mycobacterium fortuitum: A case report

RATIONALE

Rapidly growing mycobacteria (RGM) are well-known causative agents of human infections, particularly in immunocompromised hosts. However, Mycobacterium fortuitum, a predominant organism, in catheter-associated infections, has rarely been documented in totally implantable venous access port (TVIAP)-associated bloodstream infections.

PATIENT CONCERNS

A 25-year-old woman with breast cancer presented to hospital with repeated fever for several days. The patient first refused to remove the TVIAP in her body, and had a relapse of M. fortuitum bacteraemia four months later.

DIAGNOSES

Bacteria isolated from patient's blood and TVIAP were identified as M. fortuitum by Matrix-assisted laser desorption/ionization-time of flight spectrometry and bacterial 16s rDNA sequencing. The patient was diagnosed as a TVIAP-associated bloodstream infection.

INTERVENTIONS

The TVIAP was eventually surgically removed, and M. fortuitum was found to have localized on the tip of the catheter. The patient was treated by anti-infection therapy.

OUTCOMES

The patient was treated with 4 weeks of intravenous amikacin and levofloxacin followed by 4 weeks of oral levofloxacin. No episodes of fever occurred during the follow-up to date.

LESSONS

RGM infections remain a challenging issue for TIVAPs. Accurate species identification, timely intravascular catheter removal and appropriate antibiotic therapy are recommended to ensure successful outcomes.

Daptomycin versus placebo as an adjunct to beta-lactam therapy in the treatment of Staphylococcus aureus bacteremia: study protocol for a randomized controlled trial

BACKGROUND

Staphylococcus aureus bacteremia is associated with significant morbidity and mortality. To treat this infection, the current standard of care includes intravenous anti-staphylococcal beta-lactam antibiotics and obtaining adequate source control. Combination therapy with an aminoglycoside or rifampin, despite early promise, can no longer be routinely recommended due to an absence of proven benefit and risk of harm. Daptomycin is a rapidly acting bactericidal antibiotic that is approved for the treatment of Staphylococcus aureus bacteremia as monotherapy but has not been shown to be superior to the current standard of care. As demonstrated in vitro, the addition of daptomycin to beta-lactam therapy may result in enhanced anti-staphylococcal activity. Our objective is to assess the efficacy and safety of prescribing the combination of daptomycin with cefazolin or cloxacillin for the treatment of methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia in adults. We hypothesize that adjunctive therapy with daptomycin will reduce the duration of bacteremia in this population.

METHODS

The DASH-RCT trial is a randomized, double blind, placebo-controlled trial designed per the Standard Protocol Items: Recommendation for Interventional Trials (SPIRIT) and Consolidated Standards of Reporting Trials (CONSORT) guidelines. We recruit adults with confirmed MSSA bacteremia, at the McGill University Health Center. Patients are eligible if they are 18 years or older, can receive cefazolin or cloxacillin monotherapy, and are enrolled within 72 h of the first blood culture being drawn. Exclusion criteria include anaphylaxis to study drugs, having polymicrobial bacteremia, anticipated hospital admission for < 5 days, and healthcare team refusal. While receiving standard of care, study patients are randomized to a 5-day course of adjunctive daptomycin or placebo. The trial began in December 2016 and is expected to end in December 2018, after recruiting an estimated 102 patients.

DISCUSSION

The DASH-RCT will compare the use of daptomycin as an adjunct to an anti-staphylococcal beta-lactam versus placebo in the treatment of MSSA bacteremia. We believe that a short course of dual therapy will result in earlier eradication of bacteremia and that subsequent research could evaluate effects on metastatic infection, relapse, and/or mortality. Ongoing issues in the trial include a delay between presentation of infection, enrollment in the trial, and the potential for unrecognized deep foci of infection at diagnosis.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02972983 . Registered on 25 November 2016. Trial protocol: http://individual.utoronto.ca/leet/dash/dashprotocol.pdf.

Design, synthesis, DFT, docking studies and ADME prediction of some new coumarinyl linked pyrazolylthiazoles: Potential standalone or adjuvant antimicrobial agents

The control of antimicrobial resistance (AMR) seems to have come to a dead end. The major consequences of the use and abuse of antibacterial drugs are the development of resistant strains due to genetic mutability of both pathogenic and nonpathogenic microorganisms. We, herein, report the synthesis, characterization and biological activities of coumarin-thiazole-pyrazole (CTP) molecular hybrids with an effort to explore and overcome the increasing antimicrobial resistance. The compounds were characterized by analyzing their IR, Mass, 1H and13C NMR spectral data and elemental analysis. The in vitro antimicrobial activity of the synthesized compounds was investigated against various pathogenic strains; the results obtained were further explained with the help of DFT and molecular orbital calculations. Compound 1b and 1f displayed good antimicrobial activity and synergistic effects when used with kanamycin and amphotericin B. Furthermore, in vitro cytotoxicity of compounds 1b and 1f were studied against HeLa cells (cervical cancer cell) and Hek-293 cells. The results of molecular docking study were used to better rationalize the action and prediction of the binding modes of these compounds.

Comparison of Microbiological Examination by Test Tube and Congo Red Agar Methods to Detect Biofilm Production on Clinical Isolates

Biofilm on medical devices can cause significant diseases and deaths and give a large effecton disease transmission among patients and health providers and potentially increasethe cost of patient treatment. By knowing the presence of biofilm on a patient, one can differentiate the treatment management for that particular patient from the patients without biofilm on their medical device. The purpose of this study was to obtain diagnostic method to detect biofilm formation on isolates from the medical devices by simple method that is easy to do and can be applied in resource-limited microbiology laboratory. 36 specimens obtained from IV Line, CVC, urinary catheter and ETT were grown on Muller Hinton agar and continued with 3 methods, i.e., Test Tube method, Congo Red Agar method and Microtiter Plate Assay method. Results of this study showed Test Tube (nephelometer), Test Tube (visual) and Congo Red Agar in order to have the same sensitivity of 100% but has higher specificity compared to Test Tube method (visual) and Congo Red Agar method in detecting biofilm production on isolates from medical devices that had been plugged into patients body. The biofilm formation inside devices depends on factors, i.e., host, device and the microorganism itself.

Transient bacteremia induced by dental cleaning is not associated with infection of central venous catheters in patients with cancer

OBJECTIVE

The aim of this study was to determine the incidence of bacteremia resulting from dental cleaning and of subsequent established bloodstream infection (BSI) caused by oral microorganisms in patients with cancer with central venous catheters (CVCs).

STUDY DESIGN

Twenty-six patients with cancer with CVCs and absolute neutrophil count over 1000 cells/µL received dental cleaning without antibiotic prophylaxis. Periodontal status was assessed at baseline by using the Periodontal Screening and Recording (PSR) score. Blood cultures were drawn via the CVCs at baseline, 20 minutes into cleaning, and 30 minutes and 24 hours after cleaning. Medical records were monitored for 6 months.

RESULTS

Baseline blood culture results were negative in 25 patients. Nine of 25 patients (36%) had positive blood culture 20 minutes into cleaning, all associated with at least 1 microorganism typically found in the mouth. These 9 patients had significantly higher mean PSR score (3.22) compared with the other 16 (2.56; P = .035). These expected bacteremias did not persist, with blood culture results (0/25) at 30 minutes and 24 hours after cleaning showing no positivity (P = .001). There were no cases of CVC-related infection or BSI attributable to dental cleaning.

CONCLUSIONS

Bacteremia resulting from dental cleaning is transient and unlikely to cause CVC-related infection or BSI in patients with absolute neutrophil count greater than 1000 cells/µL.

Effect of chlorhexidine baths on central-line-associated bloodstream infections in a neonatal intensive care unit in a developing country

Healthcare-associated infections, particularly central-line-associated bloodstream infections (CLABSIs), are worrisome in neonates. This study describes the impact of chlorhexidine baths on CLABSI rates in a neonatal intensive care unit in a developing country, through a quasi-experimental study undertaken over 62 months (January 2012 to February 2017) divided into two periods: before and after the implementation of a protocol for chlorhexidine baths in July 2014. The rate of CLABSIs per 1000 central-line-days decreased from 8.64 to 4.28 after implementation of the protocol. The use of chlorhexidine baths appears to reduce the number of CLABSIs in neonates.

Effect of Ethanol/Trisodium Citrate Lock on Microorganisms Causing Hemodialysis Catheter-Related Infections

Purpose

This in vitro study tested the effectiveness of a novel 30% ethanol/4% trisodium citrate (TSC) lock solution against the most common pathogens causing hemodialysis catheter-related infections.

Methods

Clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) (n=4), methicillin-sensitive S. aureus (MSSA) (n=8), methicillin-resistant Staphylococcus epidermidis (MRSE) (n=8), Pseudomonas aeruginosa (n=4) and Escherichia coli (n=4) were tested in duplicate. Bacterial suspensions of each isolate were made in a control solution of normal saline and Mueller-Hinton broth (MHB), and in a lock solution of ethanol 30%, TSC 4% and MHB. Suspensions were incubated at 37 °C for 48 h. Colony counts were determined from samples collected at t=0 h (before exposure to the ethanol/TSC lock), t=1 h (one hour after exposure to the ethanol/TSC lock), t=24 h and t=48 h. To confirm the absence of viable organisms in the lock solution, the remaining volume at 48 h was filtered through a 0.45 μm filter. The filter was rinsed with 15 mL sterile water and plated on tryptic soy agar (TSA).

Results

All controls demonstrated significant growth over 48 h. In the lock solutions, initial inocula were reduced to 0 viable colonies by t=1 h (6-log kill), and there was no growth at t=24 and 48 h. Filtering of lock solutions also showed no growth. These results were consistent among duplicates of all isolates.

Conclusions

The 30% ethanol/4% TSC lock solution consistently eradicated MRSA, MSSA, MRSE, P. aeruginosa and E. coli within 1 h of exposure. Experiments are currently underway to test this novel lock solution on preventing biofilm production by these pathogens.

Candida Biofilms: Threats, Challenges, and Promising Strategies

Candida species are fungal pathogens known for their ability to cause superficial and systemic infections in the human host. These pathogens are able to persist inside the host due to the development of pathogenicity and multidrug resistance traits, often leading to the failure of therapeutic strategies. One specific feature of Candida species pathogenicity is their ability to form biofilms, which protects them from external factors such as host immune system defenses and antifungal drugs. This review focuses on the current threats and challenges when dealing with biofilms formed by Candida albicans, Candida glabrata, Candida tropicalis, and Candida parapsilosis, highlighting the differences between the four species. Biofilm characteristics depend on the ability of each species to produce extracellular polymeric substances (EPS) and display dimorphic growth, but also on the biofilm substratum, carbon source availability and other factors. Additionally, the transcriptional control over processes like adhesion, biofilm formation, filamentation, and EPS production displays great complexity and diversity within pathogenic yeasts of the Candida genus. These differences not only have implications in the persistence of colonization and infections but also on antifungal resistance typically found in Candida biofilm cells, potentiated by EPS, that functions as a barrier to drug diffusion, and by the overexpression of drug resistance transporters. The ability to interact with different species in in vivo Candida biofilms is also a key factor to consider when dealing with this problem. Despite many challenges, the most promising strategies that are currently available or under development to limit biofilm formation or to eradicate mature biofilms are discussed.

Differential time to positivity of central and peripheral blood cultures is inaccurate for the diagnosis of Staphylococcus aureus long-term catheter-related sepsis

OBJECTIVES

Differential time to positivity of cultures of blood drawn simultaneously from central venous catheter and peripheral sites is widely used to diagnose catheter-related bloodstream infections without removing the catheter. However, the accuracy of this technique for some pathogens, such as Staphylococcus aureus, is debated in routine practice.

METHODS

In a 320-bed reference cancer centre, the charts of patients with at least one blood culture positive for S. aureus among paired blood cultures drawn over a six-year period were studied retrospectively. Microbiological data were extracted from the prospectively compiled database of the microbiology unit. Data concerning the 149 patients included were reviewed retrospectively by independent physicians blinded to the absolute and differential times to positivity, in order to establish or refute the diagnosis of catheter-related sepsis. Due to missing data, 48 charts were excluded, so 101 cases were actually analysed. The diagnosis was established in 62 cases, refuted in 15 cases and inconclusive in the remaining 24 cases.

RESULTS

For the 64 patients with both central and peripheral positive blood cultures, the differential positivity time was significantly greater for patients with catheter-related bloodstream infections due to S. aureus (P<0.02). However, because of the high number of false-negative cases, the classic cut-off limit of 120 min showed 100% specificity but only 42% sensitivity for the diagnosis of catheter-related bloodstream infection due to S. aureus.

CONCLUSIONS

These results strongly suggest that despite its high specificity, the differential time to positivity may not be reliable to rule out catheter-related bloodstream infection due to S. aureus.

Biofilm Related Infections: Is There a Place for Conservative Treatment of Port-Related Bloodstream Infections?

Vascular catheters are the most frequently used indwelling medical devices and have become necessary tools for patients with chronic or critical illness. Surgically or percutaneously placed venous access ports are used to facilitate long-term intravenous therapy. The widespread use of these devices has resulted in a dramatic increase in catheter-related infections. It implies considerable morbidity, occasional mortality, and an increase in medical costs derived from its diagnosis, treatment, and mainly, prolongation of the patient's in-hospital stay. Treatment of such infections is often difficult due to the presence of biofilms on the port inner surface; inside the biofilms, bacteria are less vulnerable to antimicrobial agents. Current diagnostic strategies are suboptimal, and most successful treatment options require removal of the infected device followed by a course of antimicrobial therapy. There are limited data concerning the efficacy of antibiotic treatment of port-related bloodstream infections without catheter removal.

Treatment of dialysis catheter infections in 2004

Hemodialysis catheter associated infections are a major source of morbidity and mortality in end stage renal disease patients. There is disagreement about the management of catheter infections, particularly concerning the removal of potentially infected tunneled dialysis catheters. A dialysis catheter should generally be removed when an infection involves a temporary hemodialysis catheter, a septic patient, a patient with a tunnel tract infection, or a patient with evidence of a metastatic infectious complication. In treating stable patients with clinically mild catheter associated bacteremia, parenteral antibiotics alone have a low success rate in eliminating the infection. Antibiotic locks are an emerging strategy for treating these patients, but at present higher rates of success and lower costs are achieved by exchanging the catheter over a guidewire. Antibiotic lock solutions, antibiotic coated catheters, and totally implantable dialysis access systems may play a large role in prevention of catheter associated infections in the future; however, further randomized controlled trials of these strategies are needed. Future efforts should concentrate on limiting the use of traditional tunneled cuffed hemodialysis catheters by early referral to vascular surgery for the creation of an arterio-venous fistula.

Intra-Catheter Leukocyte Culture to Monitor Hemodialysis Catheter Colonization. a Prospective Study to Prevent Catheter-Related Bloodstream Infections

The most serious problem related to the use of tunneled catheters in hemodialysis is bacteremia. The aim of this study was to detect hemodialysis catheter colonization and, establish a preemptive therapy based on a catheter antibiotic lock in order to prevent development of catheter-related bloodstream infections. During a 24-month period, all patients with tunneled catheters in our hemodialysis unit were evaluated by extracting a through-catheter leukocyte culture every 15 days. There were 28 episodes of catheter colonization occurring in 13 patients (2.2 colonization episodes per 1000 catheter patient-days). At the time of colonization, catheters had been in place for a mean of 562 days (range: 16 to 1475 days). Coagulase negative staphylococci (CNS) were the most common microorganisms to be isolated. A preemptive therapy consisting in teicoplanin locks (10 mg/mL) for 21 days was able to eradicate catheter colonization in 89% of the cases when CNS were isolated. However, relapse of colonization occurred in 61.2% of these cases. The mean duration of catheter use was 239 days (range: 9 to 483 days) after treatment of a colonization episode. The incidence of catheter-related bloodstream infection in our population was 0.78 episodes per 1000 catheter patient-days (IC 95%: 0.374–1.434). This study shows the utility of intra-catheter leukocyte culture for early detection of hemodialysis catheter colonization. Moreover, it establishes that the eradication of biofilm-related CNS is possible without the removal of the catheter, thus enabling a longer catheter lifespan. (Int J Artif Organs 2008; 31: 820–6)

Role of Antibiotic Lock Therapy for the Treatment of Catheter-Related Bloodstream Infections

Catheter-related bloodstream infections are often difficult to treat because they are caused by organisms that embed themselves in a bio film layer on the catheter surface, resulting in an increased resistance to antimicrobial agents. Systemic antibiotics are usually administered but, although generally effective in eliminating circulating bacteria, they frequently fail to sterilize the line, leaving the patient at a continuing risk of complications or recurrence. A successful approach to managing these infections requires making an appropriate decision regarding whether the catheter should be removed or retained using antibiotic lock therapy; and choosing the type and duration of antimicrobial therapy based on the type of organism and its resistance pattern. Studies that have evaluated antibiotic lock therapy have varied in the types of antibiotics and concentrations used, the addition of heparin to the solutions, and dwell times in the catheter lumen. Guidelines from the Infectious Diseases Society of America include use of antibiotic lock therapy as a therapeutic option for intraluminal infections when the device is not removed and, although not routine, as prophylaxis for catheter-related infection in select patient populations. However, there are no published guidelines on the concentration of heparin or antibiotics that should be used, and minimal published data on the stability of heparin combinations with antibiotics. It is to be hoped that antibiotic locks will be subject to randomized controlled trials of sufficient power to confirm or refute their use.

Variation in the Practice of Central Venous Catheter and Chest Tube Insertions among Surgery Residents

Objectives

Central venous catheter (CVC) and chest tube (CT) insertions are common bedside procedures frequently performed by surgery residents. Despite published guidelines, variability in the practice exists. We sought to characterize the surgery residents' practice patterns surrounding these two bedside procedures.

Materials and Methods

Over the last 1½ months of the academic year in 2012 and 2013, surgery residents across the US were surveyed online. Participants reported levels of agreement for 15 questions in a 5-point Likert scale format.

Results

A total of 219 residents completed the survey. Majority of residents agreed that they received appropriate education and training. Over half of the respondents reported that they did not have attending staff physician's supervision during the procedures. Junior residents felt less confident in performing CVC or CT insertions. Those younger than 29 years old and of female sex were also less confident in performing CT insertion. Although almost all residents reported using maximal sterile barrier precautions, 7% reported not securing their gowns and another 7% reported inadequate draping of patients. About ⅓ reported no hand cleansing before the procedures. Those from community programs compared to university programs less frequently used antibiotics. Sixty-five percent of residents reported routine use of ultrasound for CVC insertion.

Conclusion

Surgery residents do not strictly adhere to the guidelines for CVC and CT insertions, and there is substantial variation in the practice of the procedures, which may contribute to complications associated with these procedures. This survey opens new areas for in-service education, feedback, and practices for these procedures to reduce the risk of complications, especially the infectious one.

Catheter-related blood stream infections in hemodialysis patients: a prospective cohort study

Background

For people requiring hemodialysis, infectious mortality is independently associated with geographic distance from a nephrologist. We aimed to determine if differential management of catheter-related blood stream infections (CRBSIs) could explain poorer outcomes.

Methods

We prospectively collected data from adults initiating hemodialysis with a central venous catheter between 2005 and 2015 in Alberta, Canada. We collected indicators of CRBSI management (timely catheter removal, relapsing bacteremia); frequency of CRBSIs; hospitalizations; predictors of CRBSIs, and bacteremia. We evaluated indicators and infectious episodes as a function of the shortest distance by road to the closest nephrologist’s practice: <50 (referent); 50–99; and ≥100 km.

Results

One thousand one hundred thirty-one participants were followed for a median of 755 days (interquartile range (IQR) 219, 1465) and used dialysis catheters for a median of 565 days (IQR 176, 1288). Compared to the referent group, there was no significant difference in the rate ratio (RR) of CRBSI in the 50–100 and >100 km distance categories: RR 1.63; 95% confidence interval (CI) (0.91, 2.91); RR 0.84 (95% CI 0.44, 1.58); p = 0.87, respectively or in bacteremia: RR 1.42; (95% CI 0.83, 2.45); RR 0.79 (95% CI 0.45,1.39) p = 0.74, respectively. There were no differences in indicators of appropriate CRBSI management or hospitalizations according to distance. The overall incidence of CRBSIs was low (0.19 per 1000 catheter days) as was the frequency of relapse. Only liver disease was independently associated with CRBSI (RR 2.11; 95% CI 1.15, 3.86).

Conclusions

The frequency and management of CRBSIs did not differ by location; however, event rates were low.

Vascular Access Outcomes Reported in Maintenance Hemodialysis Trials: A Systematic Review

BACKGROUND

Many randomized controlled trials have been performed with the goal of improving outcomes related to hemodialysis vascular access. If the reported outcomes are relevant and measured consistently to allow comparison of interventions across trials, such trials can inform decision making. This study aimed to assess the scope and consistency of vascular access outcomes reported in contemporary hemodialysis trials.

STUDY DESIGN

Systematic review.

SETTING & POPULATION

Adults requiring maintenance hemodialysis.

SELECTION CRITERIA

All randomized controlled trials and trial protocols reporting vascular access outcomes identified from ClinicalTrials.gov, Embase, MEDLINE, and the Cochrane Kidney and Transplant Specialized Register from January 2011 to June 2016.

INTERVENTIONS

Any hemodialysis-related intervention.

OUTCOMES

The frequency and characteristics of vascular access outcome measures were analyzed and classified.

RESULTS

From 168 relevant trials, 1,426 access-related outcome measures were extracted and classified into 23 different outcomes. The 3 most common outcomes were function (136 [81%] trials), infection (63 [38%]), and maturation (31 [18%]). Function was measured in 489 different ways, but most frequently reported as "mean access blood flow (mL/min)" (37 [27%] trials) and "number of thromboses" (30 [22%]). Infection was assessed in 136 different ways, with "number of access-related infections" being the most common measure. Maturation was assessed in 44 different ways at 15 different time points and most commonly characterized by vein diameter and blood flow. Patient-reported outcomes, including pain (19 [11%]) and quality of life (5 [3%]), were reported infrequently. Only a minority of trials used previously standardized outcome definitions.

LIMITATIONS

Restricted sampling frame for feasibility and focus on contemporary trials.

CONCLUSIONS

The reporting of access outcomes in hemodialysis trials is very heterogeneous, with limited patient-reported outcomes and infrequent use of standardized outcome measures. Efforts to standardize outcome reporting for vascular access are critical to optimizing the comparability, reliability, and value of trial evidence to improve outcomes for patients requiring hemodialysis.

Should non-bacteraemic patients with a colonized catheter receive antimicrobial therapy?

OBJECTIVES

The impact of antimicrobial therapy on the outcomes of patients with colonized catheters and no bacteraemia has not been assessed. This study assessed whether targeted antibiotic therapy is related to a poor outcome in patients with positive cultures of blood drawn through a non-tunnelled central venous catheter (CVC) and without concomitant bacteraemia.

METHODS

This was a retrospective study involving adult patients with positive blood cultures drawn through a CVC and negative peripheral vein blood cultures. Patients were classified into two groups: those with clinical improvement and those with a poor outcome. These two groups were compared. The outcome was considered poor in the presence of one or more of the following: death, bacteraemia or other infection due to the same microorganism, and evidence of catheter-related bloodstream infection.

RESULTS

A total of 100 patients were included (31 with a poor outcome). The only independent predictors of a poor outcome were a McCabe and Jackson score of 1-2 and a median APACHE score of 5. No association was found between the use of targeted antimicrobial therapy and a poor outcome when its effect was adjusted for the rest of the variables.

CONCLUSIONS

This study showed that antimicrobial therapy was not associated with a poor outcome in non-bacteraemic patients with positive blood cultures drawn through a CVC.

Microbial Endocrinology in the Pathogenesis of Infectious Disease

Microbial endocrinology represents the intersection of two seemingly disparate fields, microbiology and neurobiology, and is based on the shared presence of neurochemicals that are exactly the same in host as well as in the microorganism. The ability of microorganisms to not only respond to, but also produce, many of the same neurochemicals that are produced by the host, such as during periods of stress, has led to the introduction of this evolutionary-based mechanism which has a role in the pathogenesis of infectious disease. The consideration of microbial endocrinology-based mechanisms has demonstrated, for example, that the prevalent use of catecholamine-based synthetic drugs in the clinical setting contributes to the formation of biofilms in indwelling medical devices. Production of neurochemicals by microorganisms most often employs the same biosynthetic pathways as those utilized by the host, indicating that acquisition of host neurochemical-based signaling system in the host may have been acquired due to lateral gene transfer from microorganisms. That both host and microorganism produce and respond to the very same neurochemicals means that there is bidirectionality contained with the theoretical underpinnings of microbial endocrinology. This can be seen in the role of microbial endocrinology in the microbiota-gut-brain axis and its relevance to infectious disease. Such shared pathways argue for a role of microorganism-neurochemical interactions in infectious disease.

Cumulative Evidence of Randomized Controlled and Observational Studies on Catheter-Related Infection Risk of Central Venous Catheter Insertion Site in ICU Patients: A Pairwise and Network Meta-Analysis

BACKGROUND

Selection of central venous catheter insertion site in ICU patients could help reduce catheter-related infections. Although subclavian was considered the most appropriate site, its preferential use in ICU patients is not generalized and questioned by contradicted meta-analysis results. In addition, conflicting data exist on alternative site selection whenever subclavian is contraindicated.

OBJECTIVE

To compare catheter-related bloodstream infection and colonization risk between the three sites (subclavian, internal jugular, and femoral) in adult ICU patients.

DATA SOURCE

We searched MEDLINE, EMBASE, Cochrane Central Register of Controlled trials, CINAHL, and ClinicalTrials.gov.

STUDY SELECTION

Eligible studies were randomized controlled trials and observational ones.

DATA EXTRACTION

Extracted data were analyzed by pairwise and network meta-analysis.

DATA SYNTHESIS

Twenty studies were included; 11 were observational, seven were randomized controlled trials for other outcomes, and two were randomized controlled trials for sites. We evaluated 18,554 central venous catheters: 9,331 from observational studies, 5,482 from randomized controlled trials for other outcomes, and 3,741 from randomized controlled trials for sites. Colonization risk was higher for internal jugular (relative risk, 2.25 [95% CI, 1.84-2.75]; I = 0%) and femoral (relative risk, 2.92 [95% CI, 2.11-4.04]; I = 24%), compared with subclavian. Catheter-related bloodstream infection risk was comparable for internal jugular and subclavian, higher for femoral than subclavian (relative risk, 2.44 [95% CI, 1.25-4.75]; I = 61%), and lower for internal jugular than femoral (relative risk, 0.55 [95% CI, 0.34-0.89]; I = 61%). When observational studies that did not control for baseline characteristics were excluded, catheter-related bloodstream infection risk was comparable between the sites.

CONCLUSIONS

In ICU patients, internal jugular and subclavian may, similarly, decrease catheter-related bloodstream infection risk, when compared with femoral. Subclavian could be suggested as the most appropriate site, whenever colonization risk is considered and not, otherwise, contraindicated. Current evidence on catheter-related bloodstream infection femoral risk, compared with the other sites, is inconclusive.

Sepsis: Current Definition, Pathophysiology, Diagnosis, and Management

Sepsis is a clinical syndrome that results from the dysregulated inflammatory response to infection that leads to organ dysfunction. The resulting losses to society in terms of financial burden, morbidity, and mortality are enormous. We provide a review of sepsis, its underlying pathophysiology, and guidance for diagnosis and management of this common disease. Current established treatments include appropriate antimicrobial agents to target the underlying infection, optimization of intravascular volume to improve stroke volume, vasopressors to counteract vasoplegic shock, and high-quality supportive care. Appropriate implementation of established treatments combined with novel therapeutic approaches promises to continue to decrease the impact of this disease.

Staphylococcus aureus bacteremia in immunosuppressed patients: a multicenter, retrospective cohort study

Staphylococcus aureus bacteremia (SAB) causes significant morbidity and mortality. We assessed the disease severity and clinical outcomes of SAB in patients with pre-existing immunosuppression, compared with immunocompetent patients. A retrospective cohort investigation studied consecutive patients with SAB hospitalized across six hospitals in Toronto, Canada from 2007 to 2010. Patients were divided into immunosuppressed (IS) and immunocompetent (IC) cohorts; the IS cohort was subdivided into presence of one and two or more immunosuppressive conditions. Clinical parameters were compared between cohorts and between IS subgroups. A competing risk model compared in-hospital mortality and time to discharge. A total of 907 patients were included, 716 (79%) were IC and 191 (21%) were IS. Within the IS cohort, 111 (58%) had one immunosuppressive condition and 80 (42%) had two or more conditions. The overall in-hospital mortality was 29%, with no differences between groups (IS 32%, IC 28%, p = 0.4211). There were no differences in in-hospital mortality (sub-distribution hazard ratio [sHR] 1.17, 95% confidence interval [CI] 0.88-1.56, p = 0.2827) or time to discharge (sHR 0.94, 95% CI 0.78-1.15, p = 0.5570). Independent mortality predictors for both cohorts included hypotension at 72 h (IS: p < 0.0001, IC: p < 0.0001) and early embolic stroke (IS: p < 0.0001, IC: p = 0.0272). Congestive heart failure was a mortality predictor in the IS cohort (p = 0.0089). Fever within 24 h (p = 0.0092) and early skin and soft tissue infections (p < 0.0001) were survival predictors in the IS cohort. SAB causes significant mortality regardless of pre-existing immune status, but immunosuppressed patients do not have an elevated risk of mortality relative to immunocompetent patients.

An Unusual Occurrence of Methicillin Resistant Staphylococcal Endocarditis with Vancomycin Creep Phenomenon - A Therapeutic Challenge

Infective endocarditis by Methicillin Resistant Staphylococcus aureus (MRSA) bacteraemia is a common association and carries a high mortality. However, rising Minimum Inhibitory Concentrations (MICs) for vancomycin amongst MRSA strains is an emerging threat which carries poor prognosis and higher mortality. Here, we report a case of 41-year-old young non-addict gentleman presenting with fever of 3 days duration following recovery from an acute kidney injury necessitating haemodialysis. Systemic examination revealed signs of mitral regurgitation and left sided cerebellar signs. Laboratory investigations revealed anaemia, MRSA bacteraemia and transthoracic echocardiogram showed a mitral valve vegetation. He was diagnosed with MRSA mitral valve endocarditis with acute left cerebellar infarct. He was initially treated with intravenous vancomycin based on MIC at the dose of one gram every twelfth hourly. As the MRSA strain was shown to demonstrate a vancomycin creep phenomemon along with worsening clinical condition of the patient, treatment was changed to intravenous daptomycin at dose of 9mg/kg as per blood culture and sensitivity pattern which was administered for 6 weeks. Following initiation of daptomycin patient became afebrile and vegetations reduced in size and finally disappeared.

Complications in Aneurysmal Subarachnoid Hemorrhage Patients With and Without Subdural Electrode Strip for Electrocorticography

PURPOSE

Patients with aneurysmal subarachnoid hemorrhage (aSAH) frequently develop secondary noninfectious and infectious complications with an important impact on clinical course and outcome. In this study, we report on the rate of typical extracranial and intracranial complications in 30 prospectively enrolled patients with severe aSAH who received a linear subdural recording strip for continuous electrocorticography to detect ictal epileptiform events and spreading depolarizations.

METHODS

The group was compared with 30 retrospectively included patients with aSAH who had not received a subdural recording strip, but were treated during the same period. The control group was matched according to an aSAH grading system, sex, and establishment of external ventricular drainage, but could not be matched according to aneurysm treatment and focal brain lesions such as initial intracerebral hemorrhages.

RESULTS

No evidence was found that procedures of the electrocorticography study led to clinically relevant complications. In particular, the subdural strip did not lead to local damage of brain tissue or any increased rate of meningitis/ventriculitis. The median score on the modified Rankin Scale on day 15 was the same in both groups. Minor differences between both groups are explained by the limitations in the study design.

CONCLUSIONS

Our study suggests that neuromonitoring with a subdural recording strip for up to 15 days can be safely performed in patients with aSAH.

A Multidisciplinary Review of Nutrition Considerations in the Pediatric Oncology Population: A Perspective From Children's Oncology Group

Over the past few decades, great progress has been made in the survival rates of childhood cancer. As survival rates have improved, there has been an increased focus on supportive care. Nutrition is a supportive-care modality that has been associated with improved tolerance to chemotherapy, improved survival, increased quality of life, and decreased risk of infection in children undergoing anticancer therapy. Guidelines and assessment criteria have been proposed for the nutrition management of a child with cancer; however, there is no consistent use of criteria among institutions treating children with cancer. This review will present the current evidence and standards of practice incorporating aspects of nutrition, nursing, pharmacology, and psychosocial challenges to consider in the nutrition management of a child with cancer. Recommendations for clinical practice are presented.

Successful Clearance of Catheter-Related Bloodstream Infection by Antibiotic Lock Therapy Using Ampicillin

Objective:

To report a case in which ampicillin was used successfully as lock therapy for a central venous intravascular catheter and to discuss the implications of ampicillin used in this modality.

Case Summary:

A 14-month-old girl with a long-term central venous catheter acquired a polymicrobial (Escherichia coli and Enterococcus durans) bloodstream infection. The central venous catheter was suspected as the source for the bacteremia based on the timing and number of positive blood cultures in relation to therapy with antibiotics. Antibiotic sensitivity testing revealed ampicillin monotherapy to be an ideal choice to treat both organisms. A combination of systemic therapy via a temporary catheter and antibiotic lock therapy of the central venous catheter was then instituted using ampicillin without anticoagulants. The patient tolerated this therapy without complications, and follow-up cultures demonstrated effective clearance of the bacteria.

Discussion:

Antibiotic lock therapy has been shown to be useful in the treatment of catheter-related bloodstream infections. However, many antibiotics have yet to be tested with this modality. Ampicillin, which is frequently used in the treatment of Enterococcus and E. coli infections, has not previously been reported as a single agent for lock therapy.

Conclusions:

Ampicillin may be a useful agent with the relatively new modality of lock therapy for central venous catheters. Further studies are needed to demonstrate possible compatibility of this agent with anticoagulants, such as heparin, as well as its efficacy in treating catheter-related bloodstream infections.

Principles and Strategies for Monitoring Home Parenteral Nutrition

Patients who cannot ingest adequate calories to maintain body weight via their gastrointestinal tract may require parenteral nutrition (PN) at home. As with any therapy, the patient must be evaluated to determine if the home PN (HPN) is effective and the patient is free of complications. This review discusses specific items to monitor for HPN patients. Parameters to monitor can be divided into those used to determine effectiveness and those used to prevent complications of HPN. In addition, potential HPN-associated complications can be divided into those that occur with short- or long-term PN administration. Specific items to monitor are discussed within this framework.

Does Guidewire Exchange Influence Infection Rate Related to Catheters Used for Vascular Access in Children on Chronic Hemodialysis?

A central venous catheter (CVC) can either be inserted "de novo" or placed by guidewire exchange (GWE). From September 1998 to September 2015, 32 children (19 boys, 13 girls) were hemodialyzed in our unit by using a CVC. The mean age at CVC insertion was 12.6 ± 0.5 years. A total of 121 uncuffed catheters were placed, either "de novo" or by GWE in 64 (52.9%) and 57 (47.1%) cases, respectively. The most frequent cause for line revision was catheter dysfunction in 40/121 (33.1%) patients. The overall incidence of bacteremia was 1.5/1000 catheter-days. The incidence in newly inserted and GWE catheters was 1.4 and 1.7/1000 catheter-days, respectively. The difference did not reach statistical significance (P = 0.939). The infection rate correlated with patient age, and was higher in younger children (P = 0.006). GWE is an effective option of line revision, and did not influence the infection rate in our study.

The Incidence and Risk Factors of Nosocomial Infections in ICU

Introduction: The increased incidence of nosocomial infections in intensive care units, with frequent occurrence of multiresistant pathogens increase mortality and often raises therapeutic problems.

Objectives: to assess the incidence of nosocomial infections, and risk factors.

Methods: The study includes 125 patients hospitalized in the Clinic of Anesthesiology and Intesive Care in the Emergency County Hospital and Cardiovascular Surgery Targu Mures. The patients were divided into two groups: the control group (n = 99), patients who did not develop infections during hospitalization in the ICU and the group with infection (n = 26).

Results: The incidence of nosocomial infections in our intensive care unit was 19.1%, the most common pathogen being Acinetobacter baumanii. There were no significant differences between the two groups regarding demographic data, the most important risk factor was chronic alcohol consumption. SAPS II. and SOFA scores showed higher values in the group with infection on the day of admission. This group showed lower levels of arterial blood oxygen (Horowitz index), lower sodium level, and higher number of platelets compared to the control group. The mortality in the group with infection was 47.65% compared to the control.

Conclusions: Nosocomial infections in critically ill patients are associated with hypoxemia, thrombocytopenia, hyponatremia and a bad outcome.

Non-imaging assisted insertion of un-cuffed, non-tunneled internal jugular venous catheters for hemodialysis: Safety and utility in modern day world

Background

Absolute necessity in acute kidney injury (AKI) and ignorance in chronic kidney disease (CKD) make the use of un-cuffed, non-tunneled catheters an indispensable vascular access for hemodialysis. Although these catheters should be inserted under radiological guidance, it may not be feasible in certain circumstances. The aim of the present study was to evaluate safety and outcome of non-imaging assisted insertion of these catheters in internal jugular vein (IJV) for hemodialysis.

Methods

We analyzed 233 attempts of non-imaging assisted un-cuffed, non-tunneled IJV catheterization at our center. The immediate insertion complications, duration of use, rate and type of infection and other complications were assessed.

Results

Out of the 233 attempts, 223 (213-right, 10-left) were successful. The most common indication was AKI (n = 127, 54.5%), followed by CKD (n = 99, 42.5%). Successful catheterization at first attempt was achieved in 78.9%. Insertion complications were noted in 12.8% and included arterial puncture (5.2%), hematoma (3.0%) and malposition (2.1%). Amongst 219 catheters followed for 4825 days, the mean duration of use was 22 days. Catheter related infections occurred in 42 patients with an incidence of 8.7 per 1000 catheter days. Bacteraemia was present in 10/36 cases (27.7%), positive catheter tip cultures in 71.4% cases and staphylococcal species were the most common organism. Cumulative hazard analysis by Cox regression revealed a linear increase in the risk for infection with each week.

Conclusion

Non-imaging assisted insertion of uncuffed, non-tunneled catheters is associated with slightly higher rate of insertion complication but comparable outcome in terms of infection rate or days of use.

Guidewire exchange vs new site placement for temporary dialysis catheter insertion in ICU patients: is there a greater risk of colonization or dysfunction?

Background

Intensive care unit (ICU) patients require dialysis catheters (DCs) for renal replacement therapy (RRT). They carry a high risk of developing end-stage renal disease, and therefore their vascular access must be preserved. Guidewire exchange (GWE) is often used to avoid venipuncture insertion (VPI) at a new site. However, the impact of GWE on infection and dysfunction of DCs in the ICU is unknown. Our aim was to compare the effect of GWE and VPI on DC colonization and dysfunction in ICU patients.

Methods

Using data from the ELVIS randomized controlled trial (RCT) (1496 ICU adults requiring DC for RRT or plasma exchange) we performed a matched-cohort analysis. Cases were DCs inserted by GWE (n = 178). They were matched with DCs inserted by VPI. Matching criteria were participating centre, simplified acute physiology score (SAPS) II +/-10, insertion site (jugular or femoral), side for jugular site, and length of ICU stay before DC placement. We used a marginal Cox model to estimate the effect of DC insertion (GWE vs. VPI) on DC colonization and dysfunction.

Results

DC colonization rate was not different between GWE-DCs and VPI-DCs (10 (5.6 %) for both groups) but DC dysfunction was more frequent with GWE-DCs (67 (37.6 %) vs. 28 (15.7 %); hazard ratio (HR), 3.67 (2.07–6.49); p < 0.01). Results were similar if analysis was restricted to DCs changed for dysfunction.

Conclusions

GWE for DCs in ICU patients, compared with VPI did not contribute to DC colonization or infection but was associated with more than twofold increase in DC dysfunction.

Trial registration

This study is registered with ClinicalTrials.gov, number NCT00563342. Registered 2 April 2009.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-016-1402-6) contains supplementary material, which is available to authorized users.

Central venous catheter (CVC) removal for patients of all ages with candidaemia

BACKGROUND

Candida bloodstream infections most often affect those already suffering serious, potentially life-threatening conditions and often cause significant morbidity and mortality. Most affected persons have a central venous catheter (CVC) in place. The best CVC management in these cases has been widely debated in recent years, while the incidence of candidaemia has markedly increased.

OBJECTIVES

The main purpose of this review is to examine the impact of removing versus retaining a CVC on mortality in adults and children with candidaemia who have a CVC in place.

SEARCH METHODS

We searched the following databases from inception to 3 December 2015: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (Ovid SP), EMBASE (Ovid SP), the Commonwealth Agricultural Bureau (CAB), Web of Science and the Cumulative Index to Nursing and Allied Health Literature (CINAHL). We searched for missed, unreported and ongoing trials in trial registries and in reference lists of excluded articles.

SELECTION CRITERIA

We searched for randomized controlled trials (RCTs) and quasi-RCTs involving adults and children with candidaemia and in which participants were randomized for removal of a CVC (the intervention under study), irrespective of publication status, date of publication, blinding status, outcomes published or language.However, two major factors make the conduct of RCTs in this population a difficult task: the large sample size required to document the impact of catheter removal in terms of overall mortality; and lack of economic interest from the industry in conducting such a trial.

DATA COLLECTION AND ANALYSIS

Our primary outcome measure was mortality. Several secondary outcome measures such as required time for clearance of blood cultures for Candida species, frequency of persistent candidaemia, complications, duration of mechanical ventilation and length of stay in the intensive care unit (ICU) and in the hospital were planned, as were various subgroup and sensitivity analyses, according to our protocol. We assessed papers and abstracts for eligibility and resolved disagreements by discussion. However, we were not able to include any RCTs or quasi-RCTS in this review and, as a result, have carried out no meta-analyses. However, we have chosen to provide a brief overview of excluded observational studies.

MAIN RESULTS

We found no RCT and thus no available data for evaluation of the primary outcome (mortality) nor secondary outcomes or adverse effects. Therefore, we conducted no statistical analysis.A total of 73 observational studies reported on various clinically relevant outcomes following catheter removal or catheter retention. Most of these excluded, observational studies reported a beneficial effect of catheter removal in patients with candidaemia. None of the observational studies reported results in favour of retaining a catheter. However, the observational studies were very heterogeneous with regards to population, pathogens and interventions. Furthermore, they suffered from confounding by indication and an overall high risk of bias. As a consequence, we are not able to provide recommendations or to draw firm conclusions because of the difficulties involved in interpreting the results of these observational studies (very low quality of evidence, GRADE - Grades of Recommendation, Assessment, Development and Evaluation Working Group).

AUTHORS' CONCLUSIONS

Despite indications from observational studies in favour of early catheter removal, we found no eligible RCTs or quasi-RCTs to support these practices and therefore could draw no firm conclusions. At this stage, RCTs have provided no evidence to support the benefit of early or late catheter removal for survival or other important outcomes among patients with candidaemia; no evidence with regards to assessment of harm or benefit with prompt central venous catheter removal and subsequent re-insertion of new catheters to continue treatment; and no evidence on optimal timing of insertion of a new central venous catheter.