Microbiological testing of devices used in maintaining peripheral venous catheters

Assessment of peripheral venous catheters microbiota and its association with phlebitis

BACKGROUND

Peripheral venous catheters (PVCs) remain the primary mode of short-term venous access for managing intravenous fluid, obtaining blood samples, and peripheral parenteral nutrition. They may get contaminated and require regular monitoring to prevent complications. This study evaluated the occurrence of phlebitis and its associated-clinical and microbiological indicators.

METHODS

The frequency of phlebitis was evaluated in hospitalized patients of both medical and surgical fields. Subsequently, the dichotomous association between the presence of phlebitis and the clinical aspects was investigated. In parallel, the bacterial contamination of PVCs was assessed through culture-based methods, microscopy observation, and 16S rRNA gene sequencing.

RESULTS

Approximately one in four patients presented phlebitis (28.4%). The most frequent symptom was erythema at access site, with or without pain, corresponding to Score 1 on the phlebitis scale (17.9%). Colonization of both lumen and external surface of PVC was observed in 31.3% of the samples. Staphylococcus and Pseudomonas were the most isolated bacterial genera on the PVC surface. No significant association was observed between the presence of phlebitis and the clinical aspects, as well as the presence of microorganisms.

CONCLUSION

Microorganism were present on both internal and external PVC surface, without being associated to phlebitis.

Efficacy of disinfection procedures to reduce Acinetobacter baumanii blaOXA-23 contamination rate of needleless connectors: an in-vitro study

Aim

This study aimed to verify the efficacy of disinfection procedures to reduce Acinetobacter baumannii blaOXA-23 bacterial load in needleless connectors that had been experimentally contaminated.

Methods

Two-way intermediate extender's hub and needle-free valve were contaminated with Acinetobacter baumannii blaOXA-23. To disinfect them, the following procedures were carried out: sterile gauze with 70% ethanol, sterile gauze with Incidin®, and 70% isopropyl alcohol single-use cap, with eight times friction for 10 s, followed by 5 s drying time. The statistical tests Kruskal-Wallis and post-hoc Conover were performed using MedCalc®.

Results

A total of 82 experiments were conducted. All tested disinfection procedures were efficacious in reducing the A. baumannii blaOXA-23 load. The 70% IPA single-use cap was found to be the best method for disinfecting the two-way intermediate extender's hub (87.28%), while all the methods were efficacious for the disinfection of the needle-free valve (more than 90%). During the inoculation period, A. baumannii blaOXA-23 showed less adherence to the needle-free valve during the inoculation period, probably due to the device's design.

Conclusion

The three tested disinfection procedures using sterile gauze with 70% ethanol, sterile gauze with Incidin®, and 70% IPA single-use cap were found to be efficacious in reducing the bacterial load of A. baumanni blaOXA-23 in needleless connectors. Proper disinfection of needleless connectors is a crucial nursing practice to prevent bloodstream infections, as it significantly reduces the bacterial load present in the device.

Short Peripheral Venous Catheters Contamination and the Dangers of Bloodstream Infection in Portugal: An Analytic Study

Peripheral venous catheters (PVCs) are the most used vascular access devices in the world. However, failure rates remain considerably high, with complications such as PVC-related infections posing significant threats to patients’ well-being. In Portugal, studies evaluating the contamination of these vascular medical devices and characterizing the associated microorganisms are scarce and lack insight into potential virulence factors. To address this gap, we analyzed 110 PVC tips collected in a large tertiary hospital in Portugal. Experiments followed Maki et al.’s semi-quantitative method for microbiological diagnosis. Staphylococcus spp. were subsequently studied for the antimicrobial susceptibility profile by disc diffusion method and based on the cefoxitin phenotype, were further classified into strains resistant to methicillin. Screening for the mecA gene was also done by a polymerase chain reaction and minimum inhibitory concentration (MIC)-vancomycin as determined by E-test, proteolytic and hemolytic activity on skimmed milk 1% plate and blood agar, respectively. The biofilm formation was evaluated on microplate reading through iodonitrotetrazolium chloride 95% (INT). Overall, 30% of PVCs were contaminated, and the most prevalent genus was Staphylococcus spp., 48.8%. This genus presented resistance to penicillin (91%), erythromycin (82%), ciprofloxacin (64%), and cefoxitin (59%). Thus, 59% of strains were considered resistant to methicillin; however, we detected the mecA gene in 82% of the isolates tested. Regarding the virulence factors, 36.4% presented α-hemolysis and 22.7% β-hemolysis, 63.6% presented a positive result for the production of proteases, and 63.6% presented a biofilm formation capacity. Nearly 36.4% were simultaneously resistant to methicillin and showed expression of proteases and/or hemolysins, biofilm formation, and the MIC to vancomycin were greater than 2 µg/mL. Conclusion: PVCs were mainly contaminated with Staphylococcus spp., with high pathogenicity and resistance to antibiotics. The production of virulence factors strengthens the attachment and the permanence to the catheter’s lumen. Quality improvement initiatives are needed to mitigate such results and enhance the quality and safety of the care provided in this field.

Desinfecção de hubs e conectores de cateteres intravenosos

Objetivo: identificar métodos de desinfecção de hubs e conectores sem agulha dos cateteres intravenosos em pacientes hospitalizados e verificar a efetividade das intervenções para a prevenção de infecções de corrente sanguínea associada a cateter intravenoso. Método: revisão de escopo seguindo as recomendações de Joanna Briggs Institute. Busca realizada em bases de dados eletrônicas Pubmed, Embase, Cochrane Library, Literatura Latino-Americana e do Caribe em Ciências da Saúde, Base de Dados Enfermagem e Bibliografía Nacional en Ciencias de la Salud Argentina, e estudos indicados por experts. A busca foi atemporal até setembro de 2020. Protocolo registrado na Open Science Framework. Resultados: foram incluídos 27 estudos, sendo que cinco foram Guidelines e 22 foram artigos publicados em periódicos. Existe grande variedade de métodos de desinfecção de hubs e de conectores. Para a desinfecção ativa, foram indicados Gluconato de Clorexedina, Isopropanol e Iodopovedina; para a desinfecção passiva, Gluconato de Clorexedina e Isopropanol. A quantidade do agente desinfetante variou de 0,25 mL a 0,6 mL. O tempo de fricção na desinfecção ativa variou de cinco segundos a 30 segundos, e o tempo de contato na desinfecção passiva variou de três minutos a sete dias. O tempo de secagem de agentes desinfetantes foi superior a cinco segundos. Conclusão: verifica-se variedade de métodos de desinfecção; no entanto, não há consenso sobre a melhor indicação. Necessita-se de estudos que evidenciem a quantidade de desinfetante, a pressão e o tempo de fricção e o tempo de secagem. Pesquisas com práticas de desinfecção utilizadas no Brasil e ensaios clínicos randomizados são necessários. 

NURSING PRACTICES IN PERIPHERAL VENOUS CATHETER: PHLEBITIS AND PATIENT SAFETY

ABSTRACT Objective: to understand the nursing practices related to peripheral venous catheter and to identify deviations related to the scientific evidence regarding the prevention of phlebitis. Method: qualitative study with data collection by means of participant observation techniques and semi-structured interviews, with 26 and 15 nurses, respectively, from a Portuguese hospital. Data content analysis was performed. Results: In the category “nursing actions”, nursing practices related to: selection of catheter insertion site and its caliber size, evaluation of insertion site for signs of inflammation, insertion site dressing, disinfection of accessories, hand hygiene and patient participation in care emerged. There were situations of deviations in these practices in relation to scientific evidence. Conclusion: Nursing practices presented deviations in relation to scientific evidence, and were influenced by the size of the institution, patient characteristics, and lack of knowledge of nurses regarding certain actions that pose a risk to patient safety. The creation of protocols and the implementation of continuous education are fundamental for the acquisition of competencies by nurses, for correcting deviations and providing a safe quality nursing care to the patient.