Made available in DSpace on 2014-08-13T14:50:48Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-07-31Bitstream added on 2014-08-13T18:00:28Z : No. of bitstreams: 1 000758953.pdf: 1477838 bytes, checksum: b25f4a08fc9429595418b213fa4fb165 (MD5) / Infecções da Corrente Sanguínea Relacionadas a Cateter (ICSRC) têm se tornado a principal causa de infecção sanguínea associada à assistência a saúde e são associadas com substancial morbidade, mortalidade e excesso de custos ao hospital. Essas infecções incluem colonização do dispositivo pelos microrganismos, infecção no local de saída e uma infecção da corrente sanguínea microbiologicamente confirmada relacionada ao dispositivo. A cultura semiquantitativa é baseada no rolamento de segmento da ponta de cateter em placa contendo ágar-sangue, determinando a presença de bactérias na superfície externa do cateter e crescimento igual ou superior a 15 UFC é um indicativo de infecção. No método quantitativo descrito passa-se 1 mL de água destilada estéril pelo lúmen do cateter, agita-se e semeia-se em ágar sangue por 5 dias, considera-se significativo o crescimento maior ou igual que 103 UFC/mL, recuperando micro-organismos da superfície interna e externa do cateter. Nesse estudo, foram analisadas 584 pontas de cateter de 399 pacientes de Novembro de 2005 a Junho de 2012. As sensibilidades das técnicas semiquantitativa e quantitativa foram 72,7% e 59,3%, respectivamente, com especificidades de 95,7% e 94,4%, respectivamente. O diagnóstico de ICSRC a partir da similaridade dos isolados das pontas de cateteres e da hemocultura pela técnica genotípica PFGE revelou sensibilidade de 82,6% e especificidade de 100%. Os ECN foram os micro-organismos mais isolados. Sendo a espécie S. epidermidis a prevalente (61,0%), seguida por S. haemolyticus (13,0%), leveduras (8,7%), K. pneumoniae (8,7%), S. aureus (4,3%) e E. coli (4,3%). A resistência à Oxacilina foi encontrada em 90,9% dos ECN isolados dos casos de ICSRC, o SCCmec tipo III foi encontrado em 55,0%, o operon icaABCD em 59,0%. A CIM dos ECN para Oxacilina foi ≥0,5μg/mL para todos os isolados com exceção de um e para Vancomicina ≤4μg/mL para ... / Catheter-related bloodstream infections (CR-BSIs) have become the most common cause of healthcare-associated bloodstream infection and are associated with substantial morbidity and mortality and excess hospital costs. These infections include device colonization by microorganisms, exit site infection, and microbiologically confirmed device-related bloodstream infection. Semi-quantitative culture is used to determine the presence of microorganisms on the outer surface of the catheter, whereas quantitative culture also isolates microorganisms present inside the catheter. The objectives of this study were to compare the semi-quantitative and quantitative techniques for the diagnosis of CR-BSIs in newborns hospitalized in the neonatal ICU of HC-FMB, and to determine the incidence density and risk factors for these infections. In this study, 584 catheter tips from 399 patients seen between November 2005 and June 2012 were analyzed. The incidence density of CR-BSI varied according to newborn weight, with an incidence of 3.44/1000 catheter days in newborns <1,000 g and of 2.83/1000 catheter days in newborns >2,501 g. The sensitivity of the semi-quantitative and quantitative techniques was 72.7% and 59.3%, respectively, and specificity was 95.7% and 94.4%. The diagnosis of CR-BSI based on PFGE analysis of similarity between strains isolated from catheter tips and blood cultures showed 82.6% sensitivity and 100% specificity. Coagulase-negative staphylococci (CoNS) were the most frequently isolated microorganisms (75.9%), including S. epidermidis as the most prevalent species (65.5%), followed by S. haemolyticus (10.3%), yeasts (10.3%), K. pneumoniae (6.9%), S. aureus (3.4%), and E. coli (3.4%). Oxacillin resistance was observed in 90.9% of the CoNS isolated from cases of CR-BSI. SCCmec type III was detected in 55% of the isolates and the icaABCD operon in 59%. The oxacillin MIC was ≥0.5 μg/mL for most strains and the vancomycin MIC was ...

Orientador: Maria da Lourdes Ribeiro de Souza da Cunha / Coorientador: / Banca: Carlos Magno C. B. Fortaleza / Banca: Lígia Maria Suppo de Souza Rugolo / Resumo: Infecções da Corrente Sanguínea Relacionadas a Cateter (ICSRC) têm se tornado a principal causa de infecção sanguínea associada à assistência a saúde e são associadas com substancial morbidade, mortalidade e excesso de custos ao hospital. Essas infecções incluem colonização do dispositivo pelos microrganismos, infecção no local de saída e uma infecção da corrente sanguínea microbiologicamente confirmada relacionada ao dispositivo. A cultura semiquantitativa é baseada no rolamento de segmento da ponta de cateter em placa contendo ágar-sangue, determinando a presença de bactérias na superfície externa do cateter e crescimento igual ou superior a 15 UFC é um indicativo de infecção. No método quantitativo descrito passa-se 1 mL de água destilada estéril pelo lúmen do cateter, agita-se e semeia-se em ágar sangue por 5 dias, considera-se significativo o crescimento maior ou igual que 103 UFC/mL, recuperando micro-organismos da superfície interna e externa do cateter. Nesse estudo, foram analisadas 584 pontas de cateter de 399 pacientes de Novembro de 2005 a Junho de 2012. As sensibilidades das técnicas semiquantitativa e quantitativa foram 72,7% e 59,3%, respectivamente, com especificidades de 95,7% e 94,4%, respectivamente. O diagnóstico de ICSRC a partir da similaridade dos isolados das pontas de cateteres e da hemocultura pela técnica genotípica PFGE revelou sensibilidade de 82,6% e especificidade de 100%. Os ECN foram os micro-organismos mais isolados. Sendo a espécie S. epidermidis a prevalente (61,0%), seguida por S. haemolyticus (13,0%), leveduras (8,7%), K. pneumoniae (8,7%), S. aureus (4,3%) e E. coli (4,3%). A resistência à Oxacilina foi encontrada em 90,9% dos ECN isolados dos casos de ICSRC, o SCCmec tipo III foi encontrado em 55,0%, o operon icaABCD em 59,0%. A CIM dos ECN para Oxacilina foi ≥0,5μg/mL para todos os isolados com exceção de um e para Vancomicina ≤4μg/mL para ... / Abstract: Catheter-related bloodstream infections (CR-BSIs) have become the most common cause of healthcare-associated bloodstream infection and are associated with substantial morbidity and mortality and excess hospital costs. These infections include device colonization by microorganisms, exit site infection, and microbiologically confirmed device-related bloodstream infection. Semi-quantitative culture is used to determine the presence of microorganisms on the outer surface of the catheter, whereas quantitative culture also isolates microorganisms present inside the catheter. The objectives of this study were to compare the semi-quantitative and quantitative techniques for the diagnosis of CR-BSIs in newborns hospitalized in the neonatal ICU of HC-FMB, and to determine the incidence density and risk factors for these infections. In this study, 584 catheter tips from 399 patients seen between November 2005 and June 2012 were analyzed. The incidence density of CR-BSI varied according to newborn weight, with an incidence of 3.44/1000 catheter days in newborns <1,000 g and of 2.83/1000 catheter days in newborns >2,501 g. The sensitivity of the semi-quantitative and quantitative techniques was 72.7% and 59.3%, respectively, and specificity was 95.7% and 94.4%. The diagnosis of CR-BSI based on PFGE analysis of similarity between strains isolated from catheter tips and blood cultures showed 82.6% sensitivity and 100% specificity. Coagulase-negative staphylococci (CoNS) were the most frequently isolated microorganisms (75.9%), including S. epidermidis as the most prevalent species (65.5%), followed by S. haemolyticus (10.3%), yeasts (10.3%), K. pneumoniae (6.9%), S. aureus (3.4%), and E. coli (3.4%). Oxacillin resistance was observed in 90.9% of the CoNS isolated from cases of CR-BSI. SCCmec type III was detected in 55% of the isolates and the icaABCD operon in 59%. The oxacillin MIC was ≥0.5 μg/mL for most strains and the vancomycin MIC was ... / Mestre

Made available in DSpace on 2016-08-10T10:57:42Z (GMT). No. of bitstreams: 1 ANA VITORIA ROSA.pdf: 683707 bytes, checksum: d00aaedc3b15de8284e163af46cf4542 (MD5) Previous issue date: 2015-06-29 / Central venous catheters are very important devices in critically ill patients care. However, this device can become a threat to the health of patients, as commonly causes bloodstream infections, especially those most vulnerable. The aim of the study was to evaluate the effectiveness of chlorhexidine-impregnated coatings in central venous catheter ostium in reducing the incidence of catheter-related bloodstream infection. The method used was a systematic review study in a timeframe of eleven years, including the research published in the period from 2004 to 2014, including publications on coatings of central venous catheter ostium in the perspective of the prevention and control of infection, in search of evidences about the effectiveness of using chlorhexidine-impregnated coatings when compared to others coatings in reducing rates of catheter-related bloodstream infection. The search for articles was made through the CINAHL databases, Web of Science, EMBASE, LILACS, MEDLINE and PubMed, using the descriptors and relevant terms to each one. Seventy six publications were identified and eight fulfilled the eligibility criteria. Participants in the studies ranged from 85 to 2302 patients. The use of chlorhexidine-impregnated coating was related to the reduction of the catheterrelated infection rates and catheter-related bloodstream infection rates. The coating with chlorhexidine was well tolerated by participants, however, local reactions such as hyperemia, dermatitis and skin maceration were reported, especially in patients with multiple organ failure, subcutaneous edema or skin integrity impaired, and when remained without dressing change for more than three days. The chlorhexidineimpregnated coating presented advantages and reduction in catheter-related infection rates and in catheter-related bloodstream infection rates when compared to coating without antiseptics, besides representing a best cost-benefit ratio and reduction in mortality rate. / Cateteres venosos centrais são dispositivos de grande relevância no cuidado ao paciente crítico. Entretanto esse artefato poderá se tornar uma ameaça à saúde dos pacientes, já que comumente ocasiona infecções de corrente sanguínea, principalmente naqueles mais vulneráveis. Objetivou-se avaliar a eficácia das coberturas impregnadas com clorexidina em óstio de cateter venoso central na redução da incidência de infecção de corrente sanguínea relacionada a cateter venoso central. Foi realizado um estudo de revisão sistemática, num recorte temporal de onze anos, incluindo as pesquisas publicadas no período de 2004 a 2014, compreendendo as publicações sobre coberturas de óstio de cateter venoso central na perspectiva da prevenção e controle de infecção, em busca de evidências acerca da eficácia do uso da cobertura impregnada com clorexidina quando comparada a outras coberturas na redução das taxas de infecção da corrente sanguínea, relacionada a cateter venoso central. A busca dos artigos se deu por meio das bases de dados CINAHL, Web of Science, EMBASE, LILACS, MEDLINE e PUBMED, utilizando-se os descritores e termos pertinentes a cada uma. Identificouse 76 publicações e foram inclusas oito na revisão, por atenderem aos critérios de elegibilidade. O uso da cobertura impregnada com clorexidina apresentou vantagens e queda nas taxas de infecções quando comparada a outros curativos, estando relacionado a redução das taxas de infecção associada a cateter e das taxas de infecção da corrente sanguínea. A cobertura com clorexidina foi bem tolerada pelos participantes, no entanto, reações locais como hiperemia, dermatites e maceração da pele foram notificadas, principalmente em pacientes com falência múltipla de órgãos, edema subcutâneo e ou com a integridade da pele prejudicada, e quando o curativo permaneceu sem troca por mais de três dias. A cobertura impregnada com clorexidina apresentou vantagens e redução nas taxas de infecção relacionada a cateter e nas taxas de infecção da corrente sanguínea relacionada a cateter quando comparada as coberturas sem antissépticos, além de representar um melhor custo benefício e redução na taxa de mortalidade.

INTRODUÇÃO: As vantagens da utilização do Cateter Central de Inserção Periférica (CCIP) no ambiente hospitalar faz com que esse cateter ocupe uma posição de destaque na terapia intravenosa dos pacientes com indicação de administração de drogas com características que danificam a rede venosa periférica. A possibilidade de inserção do cateter a beira do leito por enfermeiros capacitados conferem maior facilidade para a inserção deste dispositivo. Por ser um cateter seguro e de fácil manutenção possibilita ainda a desospitalização precoce dos pacientes em antibioticoterapia e quimioterapia. Este trabalho relata o uso do CCIP nos pacientes do Instituto de Ortopedia e Traumatologia do Hospital das Clinicas da Universidade de São Paulo (IOT-HC-FMUSP) nos últimos 10 anos. MÉTODOS: Foram analisados 1.057 prontuários de pacientes submetidos a inserção do CCIP por enfermeiros qualificados no Instituto de Ortopedia e Traumatologia do Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo entre os anos de 2007 e 2017. Destes, 34 foram excluídos por não apresentar dados completos no prontuário para a análise posterior. Foram incluídos 1023 prontuários no total, onde foram analisados: idade, sexo dos pacientes, veia puncionada, diagnóstico, número de punções, tempo em que o paciente permaneceu com o cateter, motivo da retirada e posicionamento da ponta do CCIP. RESULTADOS: Um total de 1023 CCIPs inseridos durante o período de 10 anos cumpriram os critérios para inclusão neste estudo. Destes, 720 (70,4%) foram considerados adequadamente posicionados. O tempo médio de utilização do cateter foi de 34,3 dias. A veia basílica foi utilizada em 528 (51,6%) pacientes enquanto que a veia cefálica foi utilizada em 392 (38,3%) pacientes. Cento e cinquenta e sete (15,4%) cateteres foram removidos devido a complicações, sendo a oclusão a complicação mais frequentemente reportada, com 58 (5,7%) casos. Nenhum caso de trombose ou infecção relacionada ao cateter foi encontrado. Oitocentos e sessenta e seis (84,6%) pacientes completaram o tratamento. Destes, 791 (77,3%) completaram durante a hospitalização e 75 (7,3%) receberam alta com o dispositivo. A principal indicação do CCIP nos pacientes ortopédicos é a antibioticoterapia. CONCLUSÃO: Este estudo sugere que o CCIP é um dispositivo intravenoso seguro e pode ser utilizado para terapia intravenosa de média e longa duração em pacientes ortopédicos hospitalizados ou desospitalizados Benefits and risks of the peripherally inserted central catheter (PICC) / INTRODUCTION: The advantages of using a Peripherally Inserted Central Catheter (PICC) in hospitalized patients gives this dispositive great importance for the intravenous therapy, especially in patients with the indication of drugs that have a potential to damage peripheral veins. The possibility of inserting this catheter at bedside, procedure that should be realized by trained nurses, gives the use of this device an excellent choice for intravenous therapies. Also, for being a safe an easy maintain dispositive, it gives the patient the option of an early dismissal from the hospital to continue the intravenous therapy at home. This paper describes the uses of the Peripherally Inserted Central Catheter (PICC) in adult patients that used this device for intravenous therapy, and had complete information in the medical records between 2007 and 2016, at the Orthopedics and Traumatology Institute of the Clinics Hospital of the Medical School of the University of São Paulo. METHODS: This is a retrospective study in which we used 1.057 medical records from patients that receive intravenous therapy through a Peripherally Inserted Central Catheter (PICC). The procedure was carried out by trained nurses from the Orthopedics and Traumatology Institute of the Clinics Hospital of the Medical School of the University of São Paulo between 2007 and 2017. From the 1.057 medical records studied, 34 were excluded due to the lack of information or incomplete data at the time of the analyses. There were 1.023 medical files with complete information included in the study. We obtained the following information: age, gender, place of insertion, punctured vein, number of punctures, diagnosis, duration of the catheterization, complications of the catheter and positioning. RESULTS: A total of 1023 PICCs inserted during a 10 year period met eligibility criteria for this study. Of these, 720 (70.4%) were considered successfully positioned. Mean duration of catheterization was 34.3 days. The basilic vein was used in 528 (51.6%) patients, while the cephalic vein was used in 392 (38.3%) patients. One hundred and fifty seven (15.4%) catheters were removed due to complications. Of the complications, occlusion was reported in 58 (5.7%) patients. Incidence of catheter related thrombosis or infection was not found. Eight hundred and sixty six (84.6%) patients completed the treatment. Of these, 791 (77.3%) completed it during hospitalization and 75 (7.3%) were discharged with the catheter. PICCs in orthopedic patients are mainly used for antibiotic treatment. CONCLUSION: Our study suggests that PICC is a safe intravenous device that can be successfully utilized for medium and long lasting intravenous therapy in hospitalized and non-hospitalized orthopedic patients

INTRODUÇÃO: As vantagens da utilização do Cateter Central de Inserção Periférica (CCIP) no ambiente hospitalar faz com que esse cateter ocupe uma posição de destaque na terapia intravenosa dos pacientes com indicação de administração de drogas com características que danificam a rede venosa periférica. A possibilidade de inserção do cateter a beira do leito por enfermeiros capacitados conferem maior facilidade para a inserção deste dispositivo. Por ser um cateter seguro e de fácil manutenção possibilita ainda a desospitalização precoce dos pacientes em antibioticoterapia e quimioterapia. Este trabalho relata o uso do CCIP nos pacientes do Instituto de Ortopedia e Traumatologia do Hospital das Clinicas da Universidade de São Paulo (IOT-HC-FMUSP) nos últimos 10 anos. MÉTODOS: Foram analisados 1.057 prontuários de pacientes submetidos a inserção do CCIP por enfermeiros qualificados no Instituto de Ortopedia e Traumatologia do Hospital das Clinicas da Faculdade de Medicina da Universidade de São Paulo entre os anos de 2007 e 2017. Destes, 34 foram excluídos por não apresentar dados completos no prontuário para a análise posterior. Foram incluídos 1023 prontuários no total, onde foram analisados: idade, sexo dos pacientes, veia puncionada, diagnóstico, número de punções, tempo em que o paciente permaneceu com o cateter, motivo da retirada e posicionamento da ponta do CCIP. RESULTADOS: Um total de 1023 CCIPs inseridos durante o período de 10 anos cumpriram os critérios para inclusão neste estudo. Destes, 720 (70,4%) foram considerados adequadamente posicionados. O tempo médio de utilização do cateter foi de 34,3 dias. A veia basílica foi utilizada em 528 (51,6%) pacientes enquanto que a veia cefálica foi utilizada em 392 (38,3%) pacientes. Cento e cinquenta e sete (15,4%) cateteres foram removidos devido a complicações, sendo a oclusão a complicação mais frequentemente reportada, com 58 (5,7%) casos. Nenhum caso de trombose ou infecção relacionada ao cateter foi encontrado. Oitocentos e sessenta e seis (84,6%) pacientes completaram o tratamento. Destes, 791 (77,3%) completaram durante a hospitalização e 75 (7,3%) receberam alta com o dispositivo. A principal indicação do CCIP nos pacientes ortopédicos é a antibioticoterapia. CONCLUSÃO: Este estudo sugere que o CCIP é um dispositivo intravenoso seguro e pode ser utilizado para terapia intravenosa de média e longa duração em pacientes ortopédicos hospitalizados ou desospitalizados Benefits and risks of the peripherally inserted central catheter (PICC) / INTRODUCTION: The advantages of using a Peripherally Inserted Central Catheter (PICC) in hospitalized patients gives this dispositive great importance for the intravenous therapy, especially in patients with the indication of drugs that have a potential to damage peripheral veins. The possibility of inserting this catheter at bedside, procedure that should be realized by trained nurses, gives the use of this device an excellent choice for intravenous therapies. Also, for being a safe an easy maintain dispositive, it gives the patient the option of an early dismissal from the hospital to continue the intravenous therapy at home. This paper describes the uses of the Peripherally Inserted Central Catheter (PICC) in adult patients that used this device for intravenous therapy, and had complete information in the medical records between 2007 and 2016, at the Orthopedics and Traumatology Institute of the Clinics Hospital of the Medical School of the University of São Paulo. METHODS: This is a retrospective study in which we used 1.057 medical records from patients that receive intravenous therapy through a Peripherally Inserted Central Catheter (PICC). The procedure was carried out by trained nurses from the Orthopedics and Traumatology Institute of the Clinics Hospital of the Medical School of the University of São Paulo between 2007 and 2017. From the 1.057 medical records studied, 34 were excluded due to the lack of information or incomplete data at the time of the analyses. There were 1.023 medical files with complete information included in the study. We obtained the following information: age, gender, place of insertion, punctured vein, number of punctures, diagnosis, duration of the catheterization, complications of the catheter and positioning. RESULTS: A total of 1023 PICCs inserted during a 10 year period met eligibility criteria for this study. Of these, 720 (70.4%) were considered successfully positioned. Mean duration of catheterization was 34.3 days. The basilic vein was used in 528 (51.6%) patients, while the cephalic vein was used in 392 (38.3%) patients. One hundred and fifty seven (15.4%) catheters were removed due to complications. Of the complications, occlusion was reported in 58 (5.7%) patients. Incidence of catheter related thrombosis or infection was not found. Eight hundred and sixty six (84.6%) patients completed the treatment. Of these, 791 (77.3%) completed it during hospitalization and 75 (7.3%) were discharged with the catheter. PICCs in orthopedic patients are mainly used for antibiotic treatment. CONCLUSION: Our study suggests that PICC is a safe intravenous device that can be successfully utilized for medium and long lasting intravenous therapy in hospitalized and non-hospitalized orthopedic patients

Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: This thesis entails the stages of the development of an arterial catheter capable of being guided by the impedance of human tissue. Such a device would be desired in cases where it is not possible to locate the artery of a patient using anatomical landmarks. This design thus aims to improve the accuracy of first time placement of arterial catheters. The thesis entails the literature study done in order to initiate the development of said device, followed by preliminary concept design and evaluation. The thesis also contains a description of all experimental phases, done on in vitro tissue samples, in vivo samples in living porcine subjects and in vivo samples in living human patients. Experiments were performed to determine if any repeatable noticeable difference in tissue impedance could be identified and utilized in the hope of guiding this device using acquired differences in tissue impedance. The different stages of development for the prototype used in these tests are also described in detail. In addition, the results of the different tests are presented, which prove that there is a significant difference between blood tissue impedance and the surrounding tissue types encountered, allowing for guidance of the proximal tip of the arterial catheter, based on the tissue impedance measured. Finally, the thesis entails a description of further work which could be performed if this concept were to be considered as a marketable product. / AFRIKAANSE OPSOMMING: Hierdie tesis behels die verskillende stappe in die ontwerp van 'n kateter wat deur middel van die verskillende impedansie vlakke van biologiese weefsel gelei kan word in die menslikke liggaam. Sò ‘n toestel sal behulpsaam wees in gevalle waar plasing nie gedoen kan word met die behulp van anatomiese landmerke nie. Hierdie ontwerp mik dus om die akkuraatheid van die plasing van kateters te verbeter. Die tesis behels die literatuur studies benodig om sò 'n toestel te ontwerp, gevolg deur voorlopige konsep ontwerpe en die evaluasie van hierdie konsepte. Die tesis behels ook die verskillende eksperimentele fases van die projek; eksperimente op in vitro weefsel monsters, in vivo diere toetse en in vivo kliniese toetse op menslike weefsel. Al hierdie eksperimente is gedoen om te bepaal of enige herhaalbare, waarneembare verskil in weefsel impedansie geidentifiseer kan word en dus gebruik word met die hoop om diè teoretiese kateter te lei met behulp van diè verskil in weefsel impedansie. Die verskillende stappe van die ontwerp van die prototipes gebruik in hierdie eksperimente word ook in detail beskryf. Die resultate van die verskillende eksperimente word ook aangebied, wat bewys dat daar 'n beduidende verskil is tussen die impedansie van bloed weefsel en die impedansie van die aanliggende weefsel tipes, wat dus impliseer dat die proksimale punt van die kateter gelei kan word deur die gemete impedansie by die punt van die toestel, gebaseer op die resultate wat gevind is. Laastens behels die tesis ook 'n beskrywing van toekomstige werk wat gedoen kan word indien die konsep ontwikkel word tot 'n bemarkbare produk.

Neurodegenerative diseases and brain tumors affect millions of patients worldwide and are associated with significant morbidity and mortality. The blood brain barrier constitutes a major obstacle to delivery of therapeutic agents administered systemically for treating these disorders. Intracranial drug delivery provides a novel way of bypassing the blood brain barrier and achieving high concentration of therapeutic agents in the brain while avoiding systemic side effects. However damage to tissues during insertion of catheters, release of air in the brain and consequent backtracking of dye are some disadvantages with this mode of treatment. We evaluated prototype cell delivery catheters (each with outer and inner catheter) developed to minimize these complications. The catheters (1.6 mm small bore and 2.0 mm large bore) were evaluated using agarose gel and cell culture experiments. We initially delivered pheochromocytoma (PC 12) cells through a 25-gauge syringe needle to optimize cell growth. We observed in the agarose gel experiments that when the inner catheter was filled and then inserted with the outer catheter into gel, no air bubble or backtracking of dye was seen. PC 12 cells delivered through the prototype catheters appeared to growth in collagen gel and differentiate into neurons in the presence of neural growth factor. Future studies with animal experiments would be needed to confirm the findings.

A prata metálica é um conhecido agente antimicrobiano, e a sua aplicação na forma de nanopartículas de prata vem sendo apontada como uma alternativa para aplicação em dispositivos médico hospitalares. Vários métodos foram sugeridos para a prevenção da infecção relacionada ao acesso vascular, entre eles, os cateteres revestidos com nanopartículas de prata têm recebido atenção mais recentemente, por oferecerem desempenho superior em aspectos onde outros métodos falharam. Este trabalho propôs avaliar a ação de nanopartículas de prata (AgNPs) em linhagens hospitalares e sua aplicabilidade em cateteres intraluminais. Na primeira fase, 12 linhagens (3 linhagens de referência e 8 linhagens hospitalares) foram testadas frente a diferentes concentrações de nanopartículas de prata de 10 nm; e na segunda fase, duas linhagens de referência foram escolhidas para os testes com os cateteres impregnados com uma solução polimérica contendo nanopartículas de prata. Os resultados obtidos atestam que as nanopartículas de prata funcionam como uma opção para controle bactericida. / In recent years, there has been increased concern regarding the use of antimicrobials (antibiotics) in general practices and in hospital-medicine devices, a factor that may contribute for the development and selection of antibiotic-resistant strains. The metallic silver is a known antimicrobial agent. Currently, its application in the form of nanoparticles (nanosilver) has been suggested as an alternative for use in hospital medical devices. Central venous catheters (CVCs) are commonly used in critically ill patients to administer fluids, blood products and parenteral nutrition. The contamination of catheters introduced into the bloodstream and subsequent infection, severe sepsis and septic shock are associated with high morbidity and mortality. This is one of the greater challenges of treating critically ill patients. Various methods have been suggested for prevention of infection related to the vascular access, including, catheters coated with silver nanoparticles which have received attention more recently, since they offer higher performance in aspects in that other methods have failed. This alternative consists in associating nanoparticles of metallic silver to a polymeric material that coats the catheter inner and externally. The main characteristics of the coating that can potentially be ajusted are the intensity and spectrum of bactericidal activity, the rate of bactericidal releasing and resistance to biofilm formation. This work proposes to evaluate the effects of silver nanoparticles (AgNPs) in hospital strains and their applicability in intraluminal catheter. In the first stage, 12 strains (3 reference strains and 9 hospital strains) were tested against different concentrations of silver nanoparticles of 10 nm (SIGMA-Aldrich); and in the second phase, two reference strain (a Gram-positive and Gram-negative) were selected for the tests with catheters impregnated with a polymer solution containing silver nanoparticles of 10 nm (SIGMA-Aldrich). The results obtained in the first stage showed a high efficiency of nanoparticles on three reference strains - S. aureus IPT 246, P. aeruginosa IPT 322 and K. pneumoniae IPT 412-, and moderate efficiency on hospital strains - S. aureus S.a. 1 and S.a. 2; P. aeruginosa P.a. 1 and P.a.2 ; and A. baumannii Acb. 2, Acb. 4 and Acb. 8, indicating that silver nanoparticles work as an option for bacterial control. A preliminary search of silver resistance genes in the strains indicates the possibility that 5 of these strains have genes related to silver resistance similar to those described in the literature. The results obtained in the second phase show that the process of impregnation of the intraluminal catheter has reached the desired goal in both the coating device, and in reducing bioburden according the tests carried with the reference strains S. aureus 246 IPT and P. aeruginosa IPT 322.

O transporte mucociliar (TMC) é um mecanismo básico de defesa do sistema respiratório necessário na resistência à infecção. A efetividade desse mecanismo de defesa depende da composição e profundidade do muco, da integridade e da função dos cílios e da interação muco-cílio. O objetivo deste estudo foi investigar os efeitos crônicos do oxigenoterapia de baixo fluxo via cateter nasal com e sem umidificação sobre o TMC nasal, nas propriedades físicas do muco, na inflamação e nos sintomas de vias aéreas em pacientes com hipoxemia crônica com necessidade de oxigenoterapia domiciliar de longo prazo (>15 horas/dia). Dezoito pacientes (idade média de 68 anos, 7 do sexo masculino, índice de massa corpórea (IMC) médio de 26 kg/m2, 66% com doença pulmonar obstrutiva crônica (DPOC), 60% com hipertensão arterial (HAS) e ex-tabagistas) iniciando oxigenoterapia de baixo fluxo via cateter nasal foram randomizados para o grupo Oxigênio Seco (n=10) ou Oxigênio Umidificado (n=9). Os pacientes foram avaliados nos tempos: basal, 12 horas, 7 dias, 30 dias, 12 meses e 24 meses para o TMC nasal por meio do teste de trânsito da sacarina, as propriedades físicas do muco por meio de ângulo de contato, a inflamação por meio de quantificação do número total de células e diferenciais e da concentração de citocinas no lavado nasal assim como para sintomas por meio do questionário SNOT-20. O sintoma mais importante relatado por pacientes no basal foi tosse que melhorou após 7 dias de oxigenoterapia. No nosso estudo, os pacientes de ambos grupos apresentaram prolongamento significativo (40%) do TMC nasal ao longo do estudo. O lavado nasal mostrou um aumento das proporções de neutrófilos, das células caliciformes e da concentração do fator de crescimento epidermal (EGF) assim como reduções em macrófagos e concentrações de interferon alfa (IFN-alfa), interleucina (IL)-8 e IL-10 ao longo do estudo. Não houve alterações na proporção de células ciliadas, na concentração de IL-6 e no ângulo de contato do muco em ambos os grupos. A tosse e os sintomas de sono diminuiram significativamente em ambos os grupos. Nosso estudo sugere que a umidificação não tem impacto sobre o TMC nasal, as propriedades do muco, a inflamação e os sintomas em pacientes com baixo fluxo de oxigênio via cateter nasal (BFON) / Mucociliary clearance (MCC) is a basic defense mechanism of the respiratory system against respiratory infection. The efficiency of this defense mechanism depends on the mucus composition and mucus depth, on the cilia integrity and function and the mucus-cilia interaction. The aim of this study was investigate the long-term effects of low-flow oxygen via nasal catheter (NLFO) using dry oxygen (Dried-NLFO) or humidified oxygen (Humidified-NLFO) on nasal mucociliary clearance, mucus properties, inflammation and symptoms in patients with chronic hypoxemia requiring long-term domiciliary oxygen therapy ( > 15 hours/day). Eighteen patients (mean age of 68 years, 7 male, mean BMI of 26 kg/m2, 66% COPD, 60% hypertensive and former smokers) initiating NLFO were randomized to Dried-NLFO (n=10) or Humidified-NLFO (n=9). Patients were assessed at baseline and along 12 hours, 7 days, 30 days, 12 months and 24 months for nasal MCC using saccharine test, mucus properties by means of contact angle, inflammation using total number of cells and cytokines concentration in nasal lavage fluid as well as symptoms by SNOT-20 questionnaire. The most important airway symptom reported by patients at baseline was cough that improved after 7 days of oxygen therapy. In our study, nasal MCC prolonged significantly (40%) and similarly in both groups along the study. Nasal lavage showed increased proportions of neutrophils, goblet cells and epidermal growth factor concentration as decreases in macrophages, IFN-a lfa, IL-8 and IL-10 concentrations along the study. No changes in the proportion of ciliated cells, IL-6 and mucus contact angle were observed in both groups. Coughing and sleep symptoms significantly decreased similarly in both groups. Our study suggests that humidification does not impact on nasal MCC, mucus properties, inflammation and symptoms in patients using NLFO

Catheter ablation therapy attempts to restore sinus rhythm in arrhythmia patients by producing site-specific tissue modification along regions which cause abnormal electrical activity. This treatment, though widely used, often requires repeat procedures to observe long-term therapeutic benefits. This limitation is driven in part by challenges faced by conventional schemes in validating lesion adequacy at the time of the procedure. Optical techniques are well-suited for the interrogation and characterization of biological tissues. In particular, optical coherence tomography (OCT) relies on coherence gating of singly-scattered light to enable high-resolution structural imaging for tissue diagnostics and procedural guidance. Alternatively, optical reflectance spectroscopy (ORS) is a point measurement technique which makes use of incoherent, multiply-scattered light to probe tissue volumes and derive important data from its optical signature. ORS relies on the fact that light-tissue interactions are regulated by absorption and scattering, which directly relate to the intrinsic tissue biochemistry and cellular organization. In this thesis, we explore the integration of these modalities into ablation catheters for obtaining procedural metrics which could be utilized to guide catheter ablation therapy. We first present the development of an accelerated computational light transport model and its application for guiding ORS catheter design. A custom ORS-integrated ablation catheter is then implemented and tested within porcine specimens in vitro. A model is proposed for real-time estimation of lesion size based on changes in spectral morphology acquired during ablation. We then fabricated custom integrated OCT M-mode RF catheters and present a model for detecting contact status based on deep convolutional neural networks trained on endomyocardial images. Additionally, we demonstrate for the first time, tracking of RF-induced lesion formation employing OCT Doppler micro-velocimetry; this response is shown to be commensurate with the degree of treatment. We further demonstrate for the first time spectroscopic tracking of kinetics related to the heme oxidation cascade during thermal treatment, which are linked to tissue denaturation. The pairing of these modalities into a single RF catheter was also validated for guiding lesion delivery in vitro and within live pigs. Finally, we conclude with a proof-of-concept demonstration of ORS as a mapping tool to guide epicardial ablation in human donor hearts. These results showcase the vast potential of ORS and OCT empowered RF catheters for aiding intraprocedural guidance of catheter ablation procedures which could be utilized alongside current practices.