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

Central Venous Catheter Consideration in Pediatric Oncology: A Systematic Review and Meta-analysis From the American Pediatric Surgical Association Cancer Committee

BACKGROUND

Tunneled central venous catheters (CVCs) are the cornerstone of modern oncologic practice. Establishing best practices for catheter management in children with cancer is essential to optimize care, but few guidelines exist to guide placement and management.

OBJECTIVES

To address four questions: 1) Does catheter composition influence the incidence of complications; 2) Is there a platelet count below which catheter placement poses an increased risk of complications; 3) Is there an absolute neutrophil count (ANC) below which catheter placement poses an increased risk of complications; and 4) Are there best practices for the management of a central line associated bloodstream infection (CLABSI)?

METHODS

Data Sources: English language articles in Ovid Medline, PubMed, Embase, Web of Science, and Cochrane Databases.

STUDY SELECTION

Independently performed by 2 reviewers, disagreements resolved by a third reviewer.

DATA EXTRACTION

Performed by 4 reviewers on forms designed by consensus, quality assessed by GRADE methodology.

RESULTS

Data were extracted from 110 manuscripts. There was no significant difference in fracture rate, venous thrombosis, catheter occlusion or infection by catheter composition. Thrombocytopenia with minimum thresholds of 30,000-50,000 platelets/mcl was not associated with major hematoma. Limited evidence suggests a platelet count <30,000/mcL was associated with small increased risk of hematoma. While few studies found a significant increase in CLABSI in CVCs placed in neutropenic patients with ANC<500Kcells/dl, meta-analysis suggests a small increase in this population. Catheter removal remains recommended in complicated or persistent infections. Limited evidence supports antibiotic, ethanol, or hydrochloric lock therapy in definitive catheter salvage. No high-quality data were available to answer any of the proposed questions.

CONCLUSIONS

Although over 15,000 tunneled catheters are placed annually in North America into children with cancer, there is a paucity of evidence to guide practice, suggesting multiple opportunities to improve care.

LEVEL OF EVIDENCE

III. This study was registered as PROSPERO 2019 CRD42019124077.

Catheter salvage strategies in children with central venous catheter related or associated bloodstream infections: a systematic review and meta-analysis

BACKGROUND

Optimal management of Central Venous Catheter related, or associated, bloodstream infections (CRBSI or CLABSI) in children is not established.

OBJECTIVE

To evaluate successful of catheter salvage strategies in pediatric patients.

METHODS

Studies retrieved from medical databases and article reference lists. Data were collected relating to clinical outcomes of 2 treatments: systemic antibiotics alone or in association with antimicrobial lock therapy (ALT). 95% CIs and OR were calculated from a mixed logistic effects model. Heterogeneity was summarized using I2 statistics. Publication bias was investigated by Egger's regression test and funnel plots.

RESULTS

From 345 identified publications, 19 met inclusion criteria (total of 914 attempted salvage strategies. To achieve successful catheter salvage, in CRBSI the addition of ALT was superior to systemic antibiotics alone (OR -0.40, 95%CI -1.41 - 0.62): 77% (95%CI 69-85, I2=42.5%, p=0.12) and 68% of success (95%CI 59-77, I2=0, p<0.05), respectively. CRBSI recurrence was less common in studies that used ALT compared with systemic antibiotics alone: 5% (95%CI 0-13, I2=59.7%; p=0.03) and 18% of recurrence (95%CI, 9-28, I2=0, p< 0.05), respectively. Recurrences were low with both antibiotic-locks and ethanol-lock. No clear benefits of ALT addition compared to systemic antibiotic only was found in CLABSI (OR -0.81, 95% CI -0.80 - 2.43).

CONCLUSIONS

The addition of an antimicrobial lock solution to systemic antibiotic may be beneficial for successful catheter salvage in pediatric patients with CRBSI, depending on etiology, whilst no statistically significant difference between systemic antibiotic with or without addition of an antimicrobial lock solution was found regarding CLABSI.

Antibiofilm Activity of Electrical Current in a Catheter Model

Catheter-associated infections are difficult to treat with available antimicrobial agents because of their biofilm etiology. We examined the effect of low-amperage direct electrical current (DC) exposure on established bacterial and fungal biofilms in a novel experimental in vitro catheter model. Staphylococcus epidermidis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida parapsilosis biofilms were grown on the inside surfaces of polyvinyl chloride (PVC) catheters, after which 0, 100, 200, or 500 μA of DC was delivered via intraluminally placed platinum electrodes. Catheter biofilms and intraluminal fluid were quantitatively cultured after 24 h and 4 days of DC exposure. Time- and dose-dependent biofilm killing was observed with all amperages and durations of DC administration. Twenty-four hours of 500 μA of DC sterilized the intraluminal fluid for all bacterial species studied; no viable bacteria were detected after treatment of S. epidermidis and S. aureus biofilms with 500 μA of DC for 4 days.

The prevention, diagnosis and management of central venous line infections in children

With advancing paediatric healthcare, the use of central venous lines has become a fundamental part of management of neonates and children. Uses include haemodynamic monitoring and the delivery of lifesaving treatments such as intravenous fluids, blood products, antibiotics, chemotherapy, haemodialysis and total parenteral nutrition (TPN). Despite preventative measures, central venous catheter-related infections are common, with rates of 0.5-2.8/1000 catheter days in children and 0.6-2.5/1000 catheter days in neonates. Central line infections in children are associated with increased mortality, increased length of hospital and intensive care unit stay, treatment interruptions, and increased complications. Prevention is paramount, using a variety of measures including tunnelling of long-term devices, chlorhexidine antisepsis, maximum sterile barriers, aseptic non-touch technique, minimal line accessing, and evidence-based care bundles. Diagnosis of central line infections in children is challenging. Available samples are often limited to a single central line blood culture, as clinicians are reluctant to perform painful venepuncture on children with a central, pain-free, access device. With the advancing evidence basis for antibiotic lock therapy for treatment, paediatricians are pushing the boundaries of line retention if safe to do so, due to among other reasons, often limited venous access sites. This review evaluates the available paediatric studies on management of central venous line infections and refers to consensus guidelines such as those of the Infectious Diseases Society of America (IDSA).

Strategies for combating bacterial biofilm infections

Formation of biofilm is a survival strategy for bacteria and fungi to adapt to their living environment, especially in the hostile environment. Under the protection of biofilm, microbial cells in biofilm become tolerant and resistant to antibiotics and the immune responses, which increases the difficulties for the clinical treatment of biofilm infections. Clinical and laboratory investigations demonstrated a perspicuous correlation between biofilm infection and medical foreign bodies or indwelling devices. Clinical observations and experimental studies indicated clearly that antibiotic treatment alone is in most cases insufficient to eradicate biofilm infections. Therefore, to effectively treat biofilm infections with currently available antibiotics and evaluate the outcomes become important and urgent for clinicians. The review summarizes the latest progress in treatment of clinical biofilm infections and scientific investigations, discusses the diagnosis and treatment of different biofilm infections and introduces the promising laboratory progress, which may contribute to prevention or cure of biofilm infections. We conclude that, an efficient treatment of biofilm infections needs a well-established multidisciplinary collaboration, which includes removal of the infected foreign bodies, selection of biofilm-active, sensitive and well-penetrating antibiotics, systemic or topical antibiotic administration in high dosage and combinations, and administration of anti-quorum sensing or biofilm dispersal agents.