Infecção de corrente sanguínea relacionada ao uso de cateter : epidemiologia e desenvolvimento de uma cobertura biodegradável preventiva.

Abstract

Health Care-Related Infections (HCAI) are a public health problem in that they can be related to cases invasive procedures, such as catheter-related infections of real procedures (CRBSI), increasing complications of morbidity and mortality. In addition, other difficulties generated by health institutions are faced by the altered volume of environmental problems. In order to minimize these problems, this work focuses on development new biodegradable materials using promising substances, such as the biopolymer of both natural products and essential oils, already known for their biological and antimicrobial activities. Given the above, the objective of this thesis is to study the epidemiology of CRBSI and develop an antimicrobial and biodegradable catheter cover. In Article I, the results of CRBSI in patients admitted to the Neopediatric Intensive Care Unit (ICU) are presented, in which it was possible to analyze the epidemiological profile and risk factors related to the infection. A survey of the epidemiological and microbiological data of the neopediatric patients (<1 year of age) was carried out through the patient's electronic medical record and the records of the infection control commission. Among the results found, 53.2 % were male, 98.7 % were aged between 0-28 days, 57.2 % weighed between 751 - 1,500 grams at birth and, 76.6 % were born with a gestational age below 34 weeks, in which 93.5 % were considered premature. Of the cases of CRBSI, 57.1% were using some type of catheter for a period of up to 30 days. The bacterium most associated with this HAI was coagulase-negative Staphylococcus (CoNS), present in 58.6 % of the cases, 91.4 % of which were resistant to oxacillin. Finally, it was possible to identify the epidemiological profile of CRBSI in the Neopediatric ICU, with male, low birth weight and premature patients being the most affected by this HAI. In addition, the most isolated pathogenic bacterium in cultures was CoNS. Article II is a literature review that seeks to verify the methods used to analyze the antimicrobial activity and its results against microorganisms in chitosan-based biomaterials associated with essential oils for biomedical application. The search for articles was performed in the PubMed and Science Direct databases, published from 2018 to 2022, which resulted in a total of 305 articles that after, the exclusion criteria, eight articles were included. Also, they were separated into three categories, according to the final product, in: (1) film; (2) cryogel and; (3) nanofibrous scaffolds. It was possible to identify, regardless of the final product, two techniques for performing the antimicrobial activity assay: (1) agar diffusion test and (2) minimum inhibitory/microbicide concentration. Of the studies, six of them used the agar diffusion method, an assay widely known and used in microbiology laboratories. Regarding the zone of inhibition, six studies tested the chitosan biomaterial without the addition of essential oils, in which only one of them showed no inhibition for tested microorganisms. When the essential oils were incorporated, it was verified that there was synergism of the antimicrobial action against the tested strains. These results confirm that chitosan-based biomaterials, incorporated into different essential oils, are promising for biomedical applicability. Article III results of the physicochemical and antimicrobial properties of the covering composed of chitosan associated with essential oils are presented. The major compounds for the essential oils of Citrus reticulata, Eugenia caryphyllus and Origanum vulgare were, respectively, limonene, eugenol and carvacrol, characterized by gas chromatography. The developed covers were malleable and transparent, with specific coloring according to the essential oil used. Through Fourier transform infrared spectroscopy (FTIR) analysis of the coatings, specific chitosan bands were identified, in which they underwent few changes after the addition of essential oils. The morphology of the coverings was evaluated by scanning electron microscopy (SEM) and they were shown to be homogeneous, except for the essential oils of E. caryophyllus and O. vulgare, where the separation of polymer/oil phases was observed. Regarding the antimicrobial analyses, it was possible to identify a synergistic effect in the filmogenic emulsions when the essential oils were incorporated into the pure chitosan solution. Regarding the zone of inhibition, for the filmogenic emulsions containing essential oil of C. reticulata, the largest zone identified was in the concentration of 2 % (v/v), while for the associations with the essential oil of E. caryophyllus and of O. vulgare, the best results were obtained at a concentration of 3 % (v/v), against strains of Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Candida tropicalis. As for the films, the antimicrobial activity was observed for the association with E. caryophyllus 2 % (v/v) and O. vulgare 1 to 3 % (v/v) oils, except for E. coli, which did not inhibition halo was observed, but there was no antimicrobial growth below the films. This result was repeated, for the other concentrations, in the films containing essential oil of C. reticulata and E. caryophyllus, against the microorganisms tested. Given the above, it was possible to develop an antimicrobial cover with potential application in catheter covers.