Antibiotic lock with vancomycin and urokinase can successfully treat colonized central venous catheters in pediatric cancer patients

Iatrogenic vascular trauma and complications of vascular access in children

Vascular access is frequently a critical component of the diagnostic and therapeutic procedures required to manage childhood illnesses, including many emergent conditions and critical illnesses. Vascular access in the pediatric population presents unique challenges, and many clinical and technical factors must be considered to avoid complications that can occur with vascular access procedures. This article reviews various aspects of vascular access and associated iatrogenic trauma in children, including risk factors, management of complications, and preventive measures to avoid complications. It is only with a comprehensive understanding of the topic that vascular access in children can be performed safely, effectively, and efficiently.

Clinical profile and outcome of antibiotic lock therapy for bloodstream infections in pediatric hematology/oncology patients in a tertiary care hospital, Karachi, Pakistan

Background

Intravascular catheters are susceptible to infections, thus requiring catheter removal and leading to increased morbidity and costs. Antibiotic lock therapy (ALT) is a therapeutic technique that is used to salvage the catheter. The aim of this study was to evaluate the outcome of antibiotic lock therapy in bloodstream infections in pediatric hematology/oncology patients in a tertiary care hospital, Karachi.

Methods

A retrospective review was performed from January 2013 to December 2017 of pediatric hematology/oncology patients with bloodstream infections and who received ALT at Aga Khan University Hospital. All cases of polymicrobial infections, catheter removal, or malfunction before the completion of ALT were excluded. Descriptive analysis was carried out using SPSS version 20.

Results

A total of nine hematology/oncology patients were eligible. The catheter was salvaged in 7/9 (77.8%) children, and in 2/9 (22.2%) cases, catheter was removed because of persistent bacteremia. The most common organism isolated was Staphylococcus non-aureus species (33.3%). Relapse with a similar pathogen occurred in 2 (22.2%) patients and 2 (22.2%) of them developed an exit-site infection.

Conclusion

In our experience, in almost two thirds of the cases, the catheter was salvaged, but disappointingly, relapses were high when the infection was due to Staphylococcus spp. Although this is a small study, our results show that ALT can be a potential safe adjunctive strategy to treat catheter-related bloodstream infections (CRBSI). However, we need larger prospective studies to test the safety and efficacy of ALT to develop specific ALT recommendations and guidelines particularly in children.

Central venous catheter-associated bloodstream infections in pediatric hematology-oncology patients and effectiveness of antimicrobial lock therapy

BACKGROUND

Central line-associated bloodstream infection (CLABSI) is a serious complication in hematology-oncology patients. This study aimed to analyze the prevalence of CLABSI and the effectiveness of antimicrobial lock therapy (ALT) in pediatric patients.

METHODS

BSIs of all pediatric hematology-oncology patients admitted to a children's hospital between January 2009 and December 2013 were reviewed. The United States National Healthcare Safety Network and Infectious Diseases Society of America guidelines were used to define CLABSI and catheter-related BSI (CRBSI). The incidence, laboratory and microbiology characteristics, poor outcome, and effectiveness of ALT were analyzed.

RESULTS

There were 246 cases of CLABSI in 146 patients (mean age, 10.0 years), including 66 (26.8%) cases of CRBSI. The incidence of CLABSI was 4.49/1000 catheter-days, and the infection was responsible for 32.9% of the complications these patients developed and 9.3% of contributable mortality. Patients with acute myeloid leukemia had the highest infection density (5.36/1000 patient-days). Enterobacteriaceae (40.2%) and coagulase-negative staphylococci (CoNS; 20.7%) were the predominant pathogens. In multivariate analysis, older age, male sex, elevated C-reactive protein, acute lymphoblastic leukemia, and candidemia were associated with poor outcome. The success rate of ALT was 58.6% (17/29) for the treatment of CoNS and 78.3% (29/37) for Enterobacteriaceae infections. Patients with candidemia (n = 18) had the highest mortality (33.4%) and catheter removal rate (66.7%). Chlorhexidine as the disinfectant decreased the 1-year CLABSI rate from 13.7/1000 to 8.4/1000 catheter-days (p = 0.02).

CONCLUSION

CoNS and Enterobacteriaceae are the predominant pathogens in CLABSI among pediatric hematology-oncology patients. ALT is effective and showed no significant side effect. New disinfection practice and infection control measures can decrease CLABSI.

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.

Antibiotic-lock therapy for long-term catheter-related bacteremia: a review of the current evidence

Catheter-related bloodstream infections (CRBSIs) are a major cause of morbidity and mortality, especially among patients receiving hemodialysis, parenteral nutrition and chemotherapy. Antibiotic-lock therapy (ALT) represents a promising technique in the modern treatment of CRBSIs. In this review, we attempt to clarify the potential role of ALT in the treatment of long-term catheter-related bacteremia, based on the available evidence from published studies reporting on this issue. We identified 28 articles that were considered appropriate to be included in our review, only three of which were comparative studies. There is some evidence that ALT administered concurrently with systemic therapy may represent a significant therapeutic approach for CRBSIs involving long-term catheters. Prolonged infection-free catheter survival in the reported series is suggestive of sterilization of the catheters by ALT. The only reported comparison shows better outcome with ALT than with catheter exchange. Immunodeficient states, such as HIV, and the use of totally implanted devices instead of tunneled catheters may predispose to CRBSI treatment failure. No serious adverse effects, such as emergence of resistance or increased infectious complications, were found to be associated with the use of ALT in the reviewed studies. However, more comparative studies should be performed to examine this important therapeutic issue further.

Antibiotic-lock therapy: a clinical viewpoint

Antibiotic lock therapy (ALT) - instillation of high concentrations of anti-microbial agent with or without anti-coagulant into the lumen of central venous catheters - is considered a valid conservative treatment for catheter-related bloodstream infection (CRBSI) in patients highly dependent on maintaining the catheter. Results from randomized controlled studies have indicated that the effectiveness of ALT is moderate, but recent findings from experimental studies and observational case series point to considerable efficacy and safety of this therapy, which is usually associated with concomitant systemic treatment. In this article, the current knowledge about ALT for patients with CRBSI is reviewed and discussed, with emphasis on existing controversies and the results obtained according to the various uses of the catheters and the etiologies of infection.

Bench-to-bedside review: Challenges of diagnosis, care and prevention of central catheter-related bloodstream infections in children

Central venous catheters (CVCs) are indispensable in modern pediatric medicine. CVCs provide secure vascular access, but are associated with a risk of severe complications, in particular bloodstream infection. We provide a review of the recent literature about the diagnostic and therapeutic challenges of catheter-related bloodstream infection (CRBSI) in children and its prevention. Variations in blood sampling and limitations in blood culturing interfere with accurate and timely diagnosis of CRBSI. Although novel molecular testing methods appear promising in overcoming some of the present diagnostic limitations of conventional blood sampling in children, they still need to solidly prove their accuracy and reliability in clinical practice. Standardized practices of catheter insertion and care remain the cornerstone of CRBSI prevention although their implementation in daily practice may be difficult. Technology such as CVC impregnation or catheter locking with antimicrobial substances has been shown less effective than anticipated. Despite encouraging results in CRBSI prevention among adults, the goal of zero infection in children is still not in range. More high-quality research is needed in the field of prevention, accurate and reliable diagnostic measures and effective treatment of CRBSI in children.

Antibiotic and other lock treatments for tunnelled central venous catheter-related infections in children with cancer

BACKGROUND

The risk of developing a tunnelled central venous catheter (CVC)-related infection ranges between 0.1 and 2.3 per 1000 catheter days for children with cancer. These infections are difficult to treat with systemic antibiotics (salvage rate 24% - 66%) due to biofilm formation in the CVC. Lock treatments can achieve 100 - 1000 times higher concentrations locally without exposure to high systemic concentrations.

OBJECTIVES

Our objective was to investigate the efficacy of antibiotic and other lock treatments in the treatment of CVC-related infections in children with cancer compared to a control intervention. We also assessed adverse events of lock treatments.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, issue 3, 2011), MEDLINE/PubMed (1945 to August 2011) and EMBASE/Ovid (1980 to August 2011). In addition we searched reference lists from relevant articles and the conference proceedings of the International Society for Paediatric Oncology (SIOP) (from 2006 to 2010), American Society of Clinical Oncology (ASCO) (from 2006 to 2010), the Multinational Association of Supportive Care in Cancer (MASCC) (from 2006 to 2011), the American Society of Hematology (ASH) (from 2006 to 2010) and the International Society of Thrombosis and Haematology (ISTH) (from 2006 to 2011). We scanned the ISRCTN Register and the National Institute of Health Register for ongoing trials (www.controlled-trials.com) (August 2011).

SELECTION CRITERIA

Randomised controlled trials (RCTs) and controlled clinical trials (CCTs) comparing an antibiotic lock or other lock treatment (with or without concomitant systemic antibiotics) with a control intervention (other lock treatment with or without concomitant systemic antibiotics or systemic antibiotics alone) for the treatment of CVC-related infections in children with cancer. For the description of adverse events, cohort studies were also eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies, extracted data and performed 'Risk of bias' assessments of included studies. Analyses were performed according to the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

Two RCTs evaluated urokinase lock treatment with concomitant systemic antibiotics (n = 56) versus systemic antibiotics alone (n = 48), and one CCT evaluated ethanol lock treatment with concomitant systemic antibiotics (n = 15) versus systemic antibiotics alone (n = 13). No RCTs or CCTs evaluating antibiotic lock treatments were identified. All studies had methodological limitations and clinical heterogeneity between studies was present. We found no evidence of significant difference between ethanol or urokinase lock treatments with concomitant systemic antibiotics and systemic antibiotics alone regarding the number of participants cured, the number of recurrent CVC-related infections, the number of days until the first negative blood culture, the number of CVCs prematurely removed, ICU admission and sepsis. Not all studies were included in all analyses. No adverse events occurred in the five publications of cohort studies (one cohort was included in two publications) assessing this outcome; CVC malfunctioning occurred in three out of five publications of cohort studies assessing this outcome.

AUTHORS' CONCLUSIONS

No significant effect of urokinase or ethanol lock in addition to systemic antibiotics was found. However, this could be due to low power or a too-short follow-up. The cohort studies identified no adverse events; some cohort studies reported CVC malfunctioning. No RCTs or CCTs were published on antibiotic lock treatment alone. More well-designed RCTs are needed to further explore the effect of antibiotic or other lock treatments in the treatment of CVC-related infections in children with cancer.

Impact of hydrochloric acid instillation on salvage of infected central venous catheters in children with acute lymphoblastic leukaemia

BACKGROUND

Bacteraemia associated with indwelling central venous catheters (CVC) causes significant morbidity in children with cancer. Hydrochloric acid (HCl) instillations have been reported to salvage CVCs with antibiotic-refractory infection. We implemented this treatment in 2002. The impact on the survival of CVCs has been evaluated in a retrospective cohort study of children with acute lymphoblastic leukaemia (ALL).

METHODS

Children with newly diagnosed ALL during 1999-2005 having their first CVC inserted before (n = 16) and after (n = 24) the introduction of the procedure were studied. All bacteraemic episodes were reviewed, recording bacteriological findings and treatment, and the time to premature or planned removal of the CVC was determined.

RESULTS

In the comparison cohort, 31.0% (9/29) of bacteraemic episodes led to removal of the CVC, compared to 5.5% (2/36) in the intervention cohort (p = 0.01). Thus, the rate of catheter loss due to infection fell from 56.3% (9/16) to 8.3% (2/24) after introducing HCl treatment (p = 0.0025). Overall, the premature catheter removal rate fell from 75.0% (12/16) to 45.8% (11/24) (p = 0.10). Analysed in a CUSUM plot the reduced frequency of premature CVC removal evidently coincided with the introduction of the procedure. In a subgroup analysis of 21 monobacterial infections with coagulase-negative staphylococci, a decrease in systemic and lock antibiotic therapy was found. No adverse events were noted.

CONCLUSIONS

HCl instillations significantly reduced the need to remove and replace CVCs. The procedure is practical, appears to be safe, and may reduce the consumption of antibiotics.

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.

Vascular catheter-associated infections: a microbiological and therapeutic update

The increasing incidence of central venous catheter (CVC)-related infections can be ascribed to the wider indications to central venous catheterization, to the higher attention to this issue paid by clinicians and microbiologists, and to the patient population referred to hospitals, increasingly characterized by different degrees of immunosuppression and often in critical clinical conditions. This phenomenon implies a higher health care burden and higher related costs, as well as a significant attributable mortality, that varies however according to the pathogen involved. The microorganisms most frequently involved in CVC-related infections are coagulase-negative staphylococci, Staphylococcus aureus, aerobic Gram-negative bacilli, and Candida albicans. In the management of suspected or proven central venous catheter-related infections, several issues need to be addressed: the need to remove the device or the possibility of salvage, the immediate start of calculated antibiotic therapy or the possibility of waiting for results of microbiological diagnostics and proceeding to etiologically-guided therapy. The preferred conservative method is the "Antibiotic-Lock technique" (ALT), based on the endoluminal application of antibacterials at extremely high concentrations in situ for a period of time long enough to ensure bactericidal activity. On the other hand, immediate catheter removal and initiation of appropriate calculated therapy immediately after an adequate diagnostic work-up are strongly recommended in a clinical setting of severe sepsis or septic shock.

Review and update of the use of urokinase in the prevention and management of CVAD-related complications in pediatric oncology patients

Pediatric oncologists from Germany systematically reviewed the literature, considering the use of urokinase in pediatric oncology patients published since 1998 and came to the following conclusions. The use of urokinase to prevent central venous access device (CVAD)-related infections in pediatric cancer patients represents an evidence-based approach, at least in external, tunneled catheters (eg, Hickman, Broviac). The effectiveness of urokinase prophylaxis in decreasing infections and thrombotic events is probably related not only to the concentration and timing of the urokinase intervention but also to the type of CVAD, and perhaps to the intensity of the concomitant chemotherapy program. Urokinase can safely and effectively be used on CVADs with malfunctioning or intraluminal occlusion in a dose of 5000 IU/mL or as salvage 3-hour infusion with 1000 IU/kg/hour. Hitherto, adjuvant treatment with urokinase in the management of CVADs with intraluminal infection still relies on case reports and small case series. In this field, a randomized controlled study is necessary.

Pharmacodynamics of antibiotics to treat multidrug-resistant Gram-positive hospital infections

Hospital infection due to multidrug-resistant Gram-positive bacteria may often represent a life-threatening challenge; thus, to appropriately combat them, clinicians should be confident and systematically apply several important pharmacodynamic concepts. The concept of 'correct antibiotic treatment' should include, in addition to an appropriate choice in terms of antimicrobial susceptibility, an appropriate dosage and administration schedule consistent with the pharmacodynamic principles. In the next few years, it is expected that some of the anti-Gram-positive antimicrobial agents that are currently under investigation will be added to the therapeutic armamentarium. However, optimization of the usage of old drugs still remains a clinical priority and a scientific challenge, whose dignity may be considered of similar importance to that of the assessment of the possible therapeutic role of the new compounds.

Comparison of Low-Dose Gentamicin With Minocycline as Catheter Lock Solutions in the Prevention of Catheter-Related Bacteremia

BACKGROUND

Catheter-restricted antibiotic lock solutions were found to be effective in the prevention of catheter-related bacteremia (CRB), but insufficient data are available about the ideal agent and dose. We hypothesized that a low concentration of gentamicin would be as effective as the high doses studied in the past.

METHODS

In this prospective, open-labeled, randomized, clinical trial of patients on long-term hemodialysis therapy, patients were randomly assigned to administration of an antibiotic lock solution of gentamicin/citrate (4 mg/mL), minocycline/EDTA, or the control solution of heparin. Patients were followed up until the study end point of CRB was reached or a censoring event occurred. Interim data analysis was performed after 6 months to assess data safety; efficacy was noted and the study was terminated early.

RESULTS

Sixty-two patients were enrolled into the study, evenly distributed in 3 arms, with data from 1 patient excluded from analysis. Seven of 20 patients in the heparin group (4.0 events/1,000 catheter days), 1 of 21 patients in the minocycline group (0.4 events/1,000 catheter days), and none of 20 patients in the gentamicin group developed bacteremia. Results were statistically significant by using 2-tailed Fisher exact test; heparin versus gentamicin, P = 0.008, and heparin versus minocycline, P = 0.020.

CONCLUSION

Antibiotic lock solutions are superior to the standard heparin lock alone in the prevention of CRBs, and low-dose gentamicin solution has efficacy similar to that of greater concentrations used in previous studies.

Profil épidémiologique et complications des voies veineuses centrales en oncologie pédiatrique : à propos de 125 cas

OBJECTIVE

To report the indications and early and late catheter-related complications in a Tunisian unit of paediatric oncology.

PATIENTS AND METHODS

This prospective study has been performed in a paediatric oncology unit of the Salah Azaïz Institute between 1989 and 2005. It concerns 58 girls and 57 boys with a median age of 7.9 years(4 months to 18 years) treated for cancer disease predominantly lymphoma (22%), sarcoma (23.2%) or leukaemia (8.5%) proposed for insertion of a central venous catheter (CVC).

RESULTS

Excluding 2 insertion failures (1.6%), we placed 123 CVC (double for 10 patients), 43 (35%) exteriorised (EC) and 80 (65%) connected to an implantable site (IS). Catheters were placed in the subclavian vein in 59.2% of cases vs 32% for internal jugular vein and 8.8% for femoral vein. Early complications included 15 cases of multiple punctures (12%), 4 cases of pneumothorax (3.2%) and 6 of arterial punctures (4.8%) originating a cervical subcutaneous haematoma in 1 patient (0.8%). Late complications were represented by infection in 7 cases (5.7%). We observed 2 cases of intracardiac catheter migration due to catheter disconnection from the IS (1.6%) and 2 cases of thrombosis (1.8%). The mean life of CVC was longer for IS (305.2 days) than for EC (64.4 days).

CONCLUSION

Implantable sites are effective progress for venous access in children with cancer. They improved the quality of care in pediatric oncology.

Diagnosis and treatment of catheter-related infections in paediatric oncology: an update

Otherwise unexplained clinical signs of infection in patients with long-term tunnelled or totally implanted central venous access devices (CVADs) are suspected to be CVAD-associated. Diagnostic methods include catheter swabs, blood cultures and cultures of the catheter tip or port reservoir. In the case of a suspected CVAD-related bloodstream infection in paediatric oncology patients, in-situ treatment without prompt removal of the device can be attempted. Removal of the CVAD should be considered if bacteraemia persists or relapses > or = 72 h after the initiation of (in-vitro effective) antibacterial therapy administered through the line. Timely removal of the device is also recommended if the patient suffers from a complicated infection, or if Staphylococcus aureus, Pseudomonas aeruginosa, multiresistant Acinetobacter baumannii or Candida spp. are isolated from blood cultures. Duration of therapy depends on the immunological recovery of the patient, the pathogen isolated and the presence of related complications, such as thrombosis, pneumonia, endocarditis and osteomyelitis. Antibiotic lock techniques in addition to systemic treatment are beneficial for Gram-positive infections. Although prospectively controlled studies are lacking, the concomitant use of urokinase locks and taurolidine secondary prophylaxis seem to favour catheter salvage.

Hospitalist care of the medically complex child

The nature of inpatient pediatrics is changing. Over the past decade, several factors have converged to influence the kinds of children currently being hospitalized. There has been a shift in the relative proportion of otherwise healthy children with acute illnesses being hospitalized to children with increasing medical complexity. This article focuses on hospitalist care of medically complex children and provides an overview on (1) the challenges in defining this population, (2) the unique issues surrounding their inpatient care (using a family-centered care approach that includes coordinated care, minimizing secondary complications, nutritional needs, functional limitations, transdisciplinary collaboration, and primary care issues), (3) technology devices commonly found, and (4) a proposal for a research agenda regarding medically complex children.