Advances in the Diagnosis and Management of Central Venous Access Device Infections in Children

The microbial biofilm composition on peripherally inserted central catheters: A comparison of polyurethane and hydrophobic catheters collected from paediatric patients

BACKGROUND

Peripherally inserted central catheters are susceptible to microbial colonisation and subsequent biofilm formation, leading to central line-associated bloodstream infection, a serious peripherally inserted central catheter-related complication. Next-generation peripherally inserted central catheter biomaterials, such as hydrophobic materials (e.g. Endexo^®), may reduce microbial biofilm formation or attachment, consequently reducing the potential for central line-associated bloodstream infection.

METHODS

Within a randomised controlled trial, culture-dependent and culture-independent methods were used to determine if the biomaterials used in traditional polyurethane peripherally inserted central catheters and hydrophobic peripherally inserted central catheters impacted microbial biofilm composition. This study also explored the impact of other clinical characteristics including central line-associated bloodstream infection, antibiotic therapy and dwell time on the microbial biofilm composition of peripherally inserted central catheters.

RESULTS

From a total of 32 patients, one peripherally inserted central catheter was determined to be colonised with Staphylococcus aureus, and on further analysis, the patient was diagnosed with central line-associated bloodstream infection. All peripherally inserted central catheters (n = 17 polyurethane vs n = 15 hydrophobic) were populated with complex microbial communities, including peripherally inserted central catheters considered non-colonised. The two main microbial communities observed included Staphylococcus spp., dominant on the colonised peripherally inserted central catheter, and Enterococcus, dominant on non-colonised peripherally inserted central catheters. Both the peripherally inserted central catheter biomaterial design and antibiotic therapy had no significant impact on microbial communities. However, the diversity of microbial communities significantly decreased with dwell time.

CONCLUSION

More diverse pathogens were present on the colonised peripherally inserted central catheter collected from the patient with central line-associated bloodstream infection. Microbial biofilm composition did not appear to be affected by the design of peripherally inserted central catheter biomaterials or antibiotic therapy. However, the diversity of the microbial communities appeared to decrease with dwell time.

Evidence-Based Strategies and Recommendations for Preservation of Central Venous Access in Children

Children with chronic illness often require prolonged or repeated venous access. They remain at high risk for venous catheter-related complications (high-risk patients), which largely derive from elective decisions during catheter insertion and continuing care. These complications result in progressive loss of the venous capital (patent and compliant venous pathways) necessary for delivery of life-preserving therapies. A nonstandardized, episodic, isolated approach to venous care in these high-need, high-cost patients is too often the norm, imposing a disproportionate burden on affected persons and escalating costs. This state-of-the-art review identifies known failure points in the current systems of venous care, details the elements of an individualized plan of care, and emphasizes a patient-centered, multidisciplinary, collaborative, and evidence-based approach to care in these vulnerable populations. These guidelines are intended to enable every practitioner in every practice to deliver better care and better outcomes to these patients through awareness of critical issues, anticipatory attention to meaningful components of care, and appropriate consultation or referral when necessary.

Central line replacement following infection does not improve reinfection rates in pediatric pulmonary hypertension patients receiving intravenous prostanoid therapy

Treatment of pediatric pulmonary hypertension (PH) with IV prostanoids has greatly improved outcomes but requires a central line, posing inherent infection risk. This study examines the types of infections, infection rates, and importantly the effect of line management strategies on reinfection in children receiving IV prostanoids for PH. This study is a retrospective review of all pediatric PH patients receiving intravenous epoprostenol (EPO) or treprostinil (TRE) at one academic tertiary care center between 2000 and 2014. No patients declined participation in the study or were otherwise excluded. Infectious complications were characterized by organism(s), infection rates, time to next infection, and line management decisions (salvage vs. replace). Of the 40 patients followed, 13 sustained 38 infections involving 49 pathogens, with a predominance of gram-positive (GP) organisms (n = 35). The pooled infection rate was 1.06 per 1000 prostanoid days with no difference between EPO and TRE. No significant difference in reinfection rate was observed when comparing line salvage to replacement, regardless of organism type. Both overall and organism-type comparisons suggest longer time between line infections following line salvage compared with line replacement (732 vs. 410 days overall; 793 vs. 363 days for GP; 611 vs. 581 days for gram-negative [GN]; P > 0.05 for all comparisons). Central line replacement following blood stream infections in pediatric PH patients does not improve subsequent infection rates or time to next infection, and may lead to unnecessary risks associated with line replacement, including potential loss of vascular access. A revised approach to central line infections in pediatric PH is proposed.

High positive predictive value of Gram stain on catheter-drawn blood samples for the diagnosis of catheter-related bloodstream infection in intensive care neonates

Catheter-related bloodstream infections (CRBSIs) remain a leading cause of healthcare-associated infections in preterm infants. Rapid and accurate methods for the diagnosis of CRBSIs are needed in order to implement timely and appropriate treatment. A retrospective study was conducted during a 7-year period (2005-2012) in the neonatal intensive care unit of the University Hospital Erasme to assess the value of Gram stain on catheter-drawn blood samples (CDBS) to predict CRBSIs. Both peripheral samples and CDBS were obtained from neonates with clinically suspected CRBSI. Gram stain, automated culture and quantitative cultures on blood agar plates were performed for each sample. The paired quantitative blood culture was used as the standard to define CRBSI. Out of 397 episodes of suspected CRBSIs, 35 were confirmed by a positive ratio of quantitative culture (>5) or a colony count of CDBS culture >100 colony-forming units (CFU)/mL. All but two of the 30 patients who had a CDBS with a positive Gram stain were confirmed as having a CRBSI. Seven patients who had a CDBS with a negative Gram stain were diagnosed as CRBSI. The sensitivity, specificity, positive predictive value and negative predictive value of Gram stain on CDBS were 80, 99.4, 93.3 and 98.1 %, respectively. Gram staining on CDBS is a viable method for rapidly (<1 h) detecting CRBSI without catheter withdrawal.

Long-term central venous access in pediatric patients at high risk: conventional versus antibiotic-impregnated catheters

PURPOSE

To study selective use of antibiotic-impregnated catheters in children at increased risk of venous catheter-related infections (CRIs).

MATERIALS AND METHODS

From December 2008 to June 2009, 428 peripherally inserted central catheters (PICCs) were placed by the interventional radiology service of a large metropolitan children's hospital. This retrospective study analyzed demographic and outcome data for the 125 patients in this group at high risk for venous CRI. Patients at high risk were those with active systemic infection, previous complicated central venous access, intensive care unit (ICU) admission, intestinal failure, transplantation, complex congenital heart disease, or renal failure. Patients (age, 7.6 y ± 7.0; 73 male and 52 female) received a conventional or antibiotic-impregnated PICC, with 17 receiving more than one catheter.

RESULTS

Of the 146 of 428 qualifying patient encounters (34%), 53 patients received an antibiotic-impregnated PICC and 93 received a conventional PICC, representing 5,080 total catheter-days (CDs). The rates of CRIs per 1,000 CDs, including catheter exit site infections and catheter-related bloodstream infections, were 0.86 for antibiotic-impregnated PICCs and 5.5 for conventional PICCs (P = .036). A propensity-based model predicts 15-fold greater infection-free survival over the lifetime of the catheter in patients who receive an antibiotic-impregnated PICC (P < .001). Antibiotic-impregnated PICC recipients with active infection or ICU admission at the time of insertion had no catheter-associated infections, compared with 3.42 and 9.46 infections per 1,000 CDs, respectively, for patients who received conventional PICCs. Patients with intestinal failure had 1.49 and 10 infections per 1,000 CDs with antibiotic-impregnated versus conventional PICCs, respectively.

CONCLUSIONS

Antibiotic-impregnated long-term PICCs significantly improve infection-free catheter survival in pediatric patients at high risk.

Peripherally inserted central catheters for long-term parenteral nutrition in infants with intestinal failure

BACKGROUND AND AIM

Infants with intestinal failure often require long-term central access for delivery of parenteral nutrition (PN). Traditionally, surgically placed central venous catheters (CVCs) have been used; however, the complications associated with these catheters can lead to significant morbidity. Peripherally inserted central catheters (PICCs) are potentially superior to CVCs because they tend to be smaller, and can be placed without general anesthesia. The purpose of the study is to report the use of PICCs for long-term administration of PN in infants with intestinal failure and compare with previously published catheter infection and venous thrombosis rates.

METHODS

A 4-year review of infants younger than 12 months with intestinal failure and a PICC for PN delivery was performed to determine the incidence of catheter-related bloodstream infections (CRBSIs) and PICC-associated venous thrombosis. The complication rates were compared with those reported for CVCs and PICCs in the pediatric literature.

RESULTS

A total of 45 infants with intestinal failure, receiving PN through a PICC were included in the study. Data from 95 PICCs accounting for 10,189 catheter days were collected. The overall incidence of CRBSI was 5.3/1000 catheter days and the incidence of venous thrombosis was 2.0/1000 catheter days.

CONCLUSIONS

PICCs offer an advantage over CVCs in that they can often be inserted without a general anesthesia and do not require manipulation of the vein. Given the low rate of CRBSI and venous thrombosis, we recommend PICCs for infants with intestinal failure requiring PN.

Prevention of catheter-related blood stream infections in children with intestinal failure

PURPOSE OF REVIEW

Catheter-related bloodstream infections (CRBSIs) account for a major source of morbidity in children with intestinal failure. Many of these patients require long-term central venous access, placing them at significant risk for these infections. The purpose of this review is to highlight the most current strategies and interventions for minimizing CRBSIs in this population.

RECENT FINDINGS

Strategies for the prevention of CRBSIs continue to evolve, although most have not been specifically evaluated in children with intestinal failure. Some of the more recent interventions that are likely to be effective in this population include creating standardized protocols for catheter insertion and maintenance, ethanol lock therapy, and occasional use of antimicrobial catheters and dressings.

SUMMARY

Every effort must be made to prevent CRBSIs in infants and children with intestinal failure. Disease specific risk factors must be considered when determining the best approach for infection prevention. Because of their long-term access needs, checklists and protocols to maintain strict sterile technique at the time of catheter insertion are useful. Additionally, these children often have some degree of intestinal bacterial overgrowth secondary to dilation and dysmotility. Therefore, the use of antimicrobial locks, catheters and dressings likely provide benefit for some patients.

Injection of gadolinium contrast through pediatric central venous catheters: a safety study

BACKGROUND

Catheter rupture during CT angiography has prompted policies prohibiting the use of electronic injectors with peripherally inserted central venous catheters (PICCs) not only for CT but also for MRI. Consequently, many institutions mandate hand injection for MR angiography, limiting precision of infusion rates and durations of delivery.

OBJECTIVE

To determine whether electronic injection of gadolinium-based contrast media through a range of small-caliber, single-lumen PICCs would be safe without risk of catheter rupture over the range of clinical protocols and determine whether programmed flow rates and volumes were realized when using PICCs for contrast delivery.

MATERIALS AND METHODS

Experiments were performed and recorded using the Medrad Spectris Solaris EP MR Injection System. PICC sizes, contrast media and flow rates were based on common institutional protocols.

RESULTS

No catheters were damaged during any experiments. Mean difference between programmed and delivered volume was 0.07 ± 0.10 mL for all experiments. Reduced flow rates and prolonged injection durations were observed when the injector's pressure-limiting algorithm was triggered, only in protocols outside the clinical range.

CONCLUSION

PICCs commonly used in children can withstand in vitro power injection of gadolinium-based contrast media at protocols significantly above clinical levels.