Selection of the vascular catheter: can it minimise the risk of infection?

Recent developments in preventing catheter-related infections based on biofilms: A comprehensive review

Urinary and vascular catheters are among the most commonly used medical devices. However, infections caused by biofilm formation on the surface of catheters are a major cause of healthcare-associated infections. Traditional methods, such as using antimicrobials to prevent such infections, generally have short-term effects, and treatment is challenging owing to the emergence of antimicrobial-resistant bacteria. This review aims to evaluate the limitations of conventional catheter-related infection prevention efficacy, such as currently used antimicrobials, and analyze the efficacy and limitations of potential alternatives to prevent catheter-related infections that have not yet been commercialized, classified by the transition stages of biofilm formation. We intend to provide profound insights into the ideal technologies for preventing catheter-associated tract infections and present perspectives on future directions in this field.

Molecular tracking of pathogens in central venous catheter

BACKGROUND

Central venous catheter-related bloodstream infection is an important adverse event in health care. Molecular methods are not yet substitutive of microbiological in the detection of the pathogens responsible for the infection, but they can help in the epidemiological characterization.

AIM

To detect bacteria by polymerase chain reaction, from material extracted from the tip of central catheters of patients suspected of infection at the intensive care unit.

METHODS

Catheters (n = 34) of patients suspected of central venous catheter-related infection were analyzed by polymerase chain reaction. The findings were compared with culture of catheter tip and blood cultures performed by the hospital.

FINDINGS

The prevalence of bacteria was Staphylococcus aureus (50%), Enterococcus faecalis (41.2%), Klebsiella pneumoniae (32.4), Pseudomonas aeruginosa (20.6%), Acinetobacter baumannii (38.2%), Escherichia coli (2.9%), and Enterobacter cloacae (0%). No blood culture showed bacterial growth, the culture of catheter tip revealed bacteria in 21 (61.8%) and the polymerase chain reaction had positivity in 31 (91.2%) of the catheters. The mean central venous catheter time was 11 days, and the jugular vein was the site of insertion.

CONCLUSION

The molecular method identified more bacteria than microbiological methods and revealed colonization of the catheters. The most commonly found bacteria are in the environment and in the microbiota of the skin, which suggests contamination by the hands of health professionals and points out the need for more efforts in preventive strategies.

Nanomedicine: a new paradigm to overcome drug incompatibilities

OBJECTIVES

Drug incompatibilities may compromise the safety and effectiveness of combined drugs and result in mild-to-serious clinical complications, such as catheter obstruction, loss of drug efficacy, formation of toxic derivatives and embolism. Various preventive strategies have been implemented to overcome drug incompatibilities with limited success. This review presents an innovative approach to prevent drug incompatibilities via isolating the incompatible drugs into nanostructures.

KEY FINDINGS

Several examples of incompatible drugs may be loaded separately into nanostructures of various types. Physicochemical characteristics and biocompatibility of the nanomaterials that are being utilized to prevent physicochemical incompatibilities should be carefully considered.

CONCLUSIONS

There is a new era of exploiting nanomaterials in overcoming various types of physicochemical incompatibilities, with additional benefits of further improvements in pharmacokinetic profiles and pharmacological actions of the administered drugs.

Multifunctional "Hydrogel Skins" on Diverse Polymers with Arbitrary Shapes

Slippery and hydrophilic surfaces find critical applications in areas as diverse as biomedical devices, microfluidics, antifouling, and underwater robots. Existing methods to achieve such surfaces rely mostly on grafting hydrophilic polymer brushes or coating hydrogel layers, but these methods suffer from several limitations. Grafted polymer brushes are prone to damage and do not provide sufficient mechanical compliance due to their nanometer-scale thickness. Hydrogel coatings are applicable only for relatively simple geometries, precluding their use for the surfaces with complex geometries and features. Here, a new method is proposed to interpenetrate hydrophilic polymers into the surface of diverse polymers with arbitrary shapes to form naturally integrated "hydrogel skins." The hydrogel skins exhibit tissue-like softness (Young's modulus ≈ 30 kPa), have uniform and tunable thickness in the range of 5-25 µm, and can withstand prolonged shearing forces with no measurable damage. The hydrogel skins also provide superior low-friction, antifouling, and ionically conductive surfaces to the polymer substrates without compromising their original mechanical properties and geometry. Applications of the hydrogel skins on inner and outer surfaces of various practical polymer devices including medical tubing, Foley catheters, cardiac pacemaker leads, and soft robots on massive scales are further demonstrated.

Comparative Efficacy of Antimicrobial Central Venous Catheters in Reducing Catheter-Related Bloodstream Infections in Adults: Abridged Cochrane Systematic Review and Network Meta-Analysis

Background

The efficacy of antimicrobial central venous catheters (CVCs) remains questionable. In this network meta-analysis, we aimed to assess the comparative efficacy of antimicrobial CVC impregnations in reducing catheter-related infections in adults.

Methods

We searched 4 electronic databases (Medline, the Cochrane Central Register of Controlled Trials, Embase, CINAHL) and internet sources for randomized controlled trials, ongoing clinical trials, and unpublished studies up to August 2016. Studies that assessed CVCs with antimicrobial impregnation with nonimpregnated catheters or catheters with another impregnation were included. Primary outcomes were clinically diagnosed sepsis, catheter-related bloodstream infection (CRBSI), and all-cause mortality. We performed a network meta-analysis to estimate risk ratio (RR) with 95% confidence interval (CI).

Results

Sixty studies with 17255 catheters were included. The effects of 14 impregnations were investigated. Both CRBSI and catheter colonization were the most commonly evaluated outcomes. Silver-impregnated CVCs significantly reduced clinically diagnosed sepsis compared with silver-impregnated cuffs (RR, 0.54 [95% CI, .29-.99]). When compared to no impregnation, significant CRBSI reduction was associated with minocycline-rifampicin (RR, 0.29 [95% CI, .16-.52]) and silver (RR, 0.57 [95% CI, .38-.86]) impregnations. No impregnations significantly reduced all-cause mortality. For catheter colonization, significant decreases were shown by miconazole-rifampicin (RR, 0.14 [95% CI, .05-.36]), 5-fluorouracil (RR, 0.34 [95% CI, .14-.82]), and chlorhexidine-silver sulfadiazine (RR, 0.60 [95% CI, .50-.72]) impregnations compared with no impregnation. None of the studies evaluated antibiotic/antiseptic resistance as the outcome.

Conclusions

Current evidence suggests that the minocycline-rifampicin-impregnated CVC appears to be the most effective in preventing CRBSI. However, its overall benefits in reducing clinical sepsis and mortality remain uncertain. Surveillance for antibiotic resistance attributed to the routine use of antimicrobial-impregnated CVCs should be emphasized in future trials.

Complications of intravascular catheters in ICU: definitions, incidence and severity. A randomized controlled trial comparing usual transparent dressings versus new-generation dressings (the ADVANCED study)

PURPOSE

To describe all post-insertion complications involving most used intravascular access, and to determine whether the use of a new-generation transparent dressing (3M™ IV Advanced) might reduce their number and impact on ICU patient outcomes.

METHODS

Patients older than 18, with an expected length of stay ≥48 h and requiring at least one central venous catheter (CVC), arterial catheter (AC), haemodialysis catheter (HDC), pulmonary arterial catheters (PAC) or peripheral venous catheter (PVC) were randomized into two groups: a new-generation transparent dressing, or the hospital's classical transparent dressing, and were followed daily for any infectious and non-infectious complications. Complications were graduated for severity by an independent international multicentre multidisciplinary panel of practitioners using a Delphi process.

RESULTS

We included 628 patients, 2214 catheters (873 PVCs, 630 CVCs, 512 ACs and 199 HDCs and PACs) and 4836 dressings. Overall incidence rate was of 60.9/1000 catheter-days. The most common complication was dysfunction (34.6/1000 catheter-days), mainly for PVCs (16/1000 catheter-days) and ACs (12.9/1000 catheter-days). Infectious complications incidence rate in CVCs and ACs was of 14.5/1000, mostly due to colonization (14.2/1000 catheter-days). Thrombosis incidence was of 3.8/1000 catheter-days with severe and very severe complications in 16 cases (1.8/1000 catheter-days) and one thrombosis-related death. 3M™ IV Advanced dressing did not decrease the rate of catheters with at least a minor complication [57.37/1000 vs. 57.52/1000 catheter-days, HR 1.03, CI (0.84-1.27), p = 0.81]. Incidence rates for each single complication remained equivalent: infectious [HR 0.93 (0.62-1.40), p = 0.72], deep thrombosis [HR 0.90 (0.39-2.06), p = 0.80], extravasation and phlebitis [HR 1.40 (0.69-2.82), p = 0.35], accidental removal [1.07 (0.56-2.04), p = 0.84] and dysfunction [HR 1.04 (0.80-1.35), p = 0.79].

CONCLUSION

The ADVANCED study showed the overall risk of complications to intravascular catheters in ICU patients being dysfunction, infection and thrombosis. The 3M™ IV Advanced dressing did not decrease complication rates as compared to standard dressings.

Risk management of onco-hematological drugs: how and how fast can we improve?

PURPOSE

Medication errors in oncology may cause severe damage to patients, professionals, and the environment. The Italian Ministry of Health issued Raccomandazione 14 to provide guidelines for prevention of errors while using antineoplastic drugs. This work aimed at analyzing Raccomandazione 14 through the different viewpoints of the hospital pharmacist, the nurse, the oncologist, and the hospital director.

METHODS

Twenty-seven Italian healthcare organizations participated in a self-assessment survey evaluating compliance with Raccomandazione 14 within the oncology, hematology, and pharmacy departments.

RESULTS

The self-assessment results showed a general acknowledgement of the need for centralized management of anticancer agents. The specific responsibility of the pharmacist on the centralized management of anticancer drugs from preparation to disposal emerged as a critical point. The nurse, beyond the skills in drug administration and prevention of extravasation, also plays a fundamental role in educating and supporting the patient. The physicians, who are attentive to scientific, clinical, and regulatory criteria in prescribing and monitoring the therapies, are called upon to improve awareness on the importance of sharing standardized procedures with other professionals, to minimize medication error occurrence. The implementation of a complete computerized management from prescribing to drug administration and follow-up was highlighted. Multidisciplinary groups were constituted across the nation by professionals dedicated to the implementation of electronic health records and drug history and medical reconciliation processes.

CONCLUSIONS

Our analysis of the Ministerial Raccomandazione 14 urges implementation of the resources for ensuring quality and safety during prescription, preparation, and administration of anticancer drugs.

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.

Clinical guidelines on central venous catheterisation. Swedish Society of Anaesthesiology and Intensive Care Medicine

Safe and reliable venous access is mandatory in modern health care, but central venous catheters (CVCs) are associated with significant morbidity and mortality, This paper describes current Swedish guidelines for clinical management of CVCs The guidelines supply updated recommendations that may be useful in other countries as well. Literature retrieval in the Cochrane and Pubmed databases, of papers written in English or Swedish and pertaining to CVC management, was done by members of a task force of the Swedish Society of Anaesthesiology and Intensive Care Medicine. Consensus meetings were held throughout the review process to allow all parts of the guidelines to be embraced by all contributors. All of the content was carefully scored according to criteria by the Oxford Centre for Evidence-Based Medicine. We aimed at producing useful and reliable guidelines on bleeding diathesis, vascular approach, ultrasonic guidance, catheter tip positioning, prevention and management of associated trauma and infection, and specific training and follow-up. A structured patient history focused on bleeding should be taken prior to insertion of a CVCs. The right internal jugular vein should primarily be chosen for insertion of a wide-bore CVC. Catheter tip positioning in the right atrium or lower third of the superior caval vein should be verified for long-term use. Ultrasonic guidance should be used for catheterisation by the internal jugular or femoral veins and may also be used for insertion via the subclavian veins or the veins of the upper limb. The operator inserting a CVC should wear cap, mask, and sterile gown and gloves. For long-term intravenous access, tunnelled CVC or subcutaneous venous ports are preferred. Intravenous position of the catheter tip should be verified by clinical or radiological methods after insertion and before each use. Simulator-assisted training of CVC insertion should precede bedside training in patients. Units inserting and managing CVC should have quality assertion programmes for implementation and follow-up of routines, teaching, training and clinical outcome. Clinical guidelines on a wide range of relevant topics have been introduced, based on extensive literature retrieval, to facilitate effective and safe management of CVCs.

The choice of vascular access for therapeutic apheresis

Therapeutic apheresis (TA) is performed using either centrifugation-based or filter-based systems. The blood flow rate (BFR) used for TA using centrifugation-based systems is less than 100 mL/min. Because of this low BFR requirement, even peripheral veins can be considered as an option for TA, especially for less-frequent treatments and those performed for short periods. Other options for vascular access (VA) include central venous catheters (temporary or tunneled), totally implantable ports, and arteriovenous fistulae (AVF) or grafts (AVG). Nontunneled catheters should be considered as the choice of VA for relatively short-term treatments mainly in the inpatient settings. For long-term treatments, ports and tunneled catheters should be considered because of lower rates of infections compared to nontunneled catheters. However, studies in hemodialysis (HD) patients have demonstrated significantly higher morbidity and mortality rates associated with the use of tunneled catheters as compared to AVF. Therefore, if TA is being considered for several years, AVG and AVF would be the preferred options of VA. Studies in HD population indicate far better outcomes with the use of AVF as compared to AVG. This article, as presented at the Therapeutic Apheresis Academy in September 2011, is an overview of the available VA options for TA based on indication and duration of treatment. Pros and cons of each option are mentioned briefly. Finally, for those considered for AVF placement for chronic TA, specific recommendations are made for the care of AVF based on our own experience at University of Virginia.