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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

The Independent Effect of Three Inline Suction Adapters and Lung Compliance change on Amplitude and delivered Tidal Volume during High Frequency Oscillatory Ventilation in an adult patient with ARDS: Bench Model

Thacker, Shreya 01 August 2011 (has links)
Introduction: The use of high frequency oscillatory ventilation is increasing in treatment ofacute respiratory distress syndrome over the past decade. The technique of HFOV of ventilatingthe lungs at volumes less than the anatomical dead space calms the clinical concerns surroundingventilating stiff ARDS lungs with high pressures and volumes. This largely reduces theprobability of barotraumas and/or atelectrauma. Purpose: The study was on an in vitro bench model that answered the following researchquestions: 1. The effect of three inline closed suction adapters on delivered tidal volume duringHFOV with varying lung compliance 2. The effect of varying compliance on the amplitudedelivered by HFOV; and 3. The effect of compliance on tidal volume delivered by HFOV. Method: An in vitro bench model using high fidelity breathing simulator (ASL 5000, IngMarMedical) simulating an adult patient with ARDS was set up with 3100B SensorMedic highfrequency ventilator. The simulation included varying the compliance for each lung at 50, 40, 30and 20cmH2O while maintaining fixed resistance of 15 cmH2O/L/sec. The ventilator was set tothe following parameters: power of 6, frequency (f) of 5, inspiratory time (Ti) of 33%, bias flow(BF) of 30 LPM and oxygen concentration of 50%. The breathing simulator was connected withthe high frequency ventilator using a standard HFOV circuit and a size 8.0mm of endotrachealtube. Fourteen French Kimberly Clark suction catheters (with T and Elbow adapters) and Air-Life suction catheters (Y adapter) were placed in-line with the circuit successively to carry outthe study. Each run lasted for 1 minute after achieving stable state conditions. Thisapproximated to 300 breaths. The data was collected from the stimulator and stored by the hostcomputer. Data Analysis: The data was analyzed using SPSS v.11 to determine the statistical significance.A probability value (P value) of ≤ 0.001 was considered to be statistically significant. Results: The data analysis showed that Air-Life Y-adapter suction catheters caused the least lostin tidal volume when placed in line with HFOV and hence proved to be the most efficient. Thestudy also showed a direct relationship between amplitude and lung compliance i.e. an increasein lung compliance caused an associated increase in amplitude (power setting remainingunaltered). Lastly, the study did not show a statistically significant change in tidal volume withchanges in lung compliance. Future studies may be required to further evaluate the clinicalsignificance of the same. Conclusion:1. Many factors affect delivery of tidal volume during high frequency ventilation and thus it isnot constant. Choice of in-line suction system to be placed in line is one of the determinants ofthe same.2. Lung compliance changes lead to associated changes in amplitude delivery by HFOV. Thisshould be adjusted as patient condition improves by altering the power settings to ensure optimalventilation and to avoid trauma to the lungs.
92

Développements méthodologiques pour l'Imagerie par Résonance Magnétique de l’hélium 3 hyperpolarisé et applications / Hyperpolarized helium3 Magnetic Resonance Imaging methodological developments and applications on a clinical scanner

Bannier, Élise 14 January 2009 (has links)
Cette thèse porte sur la mise en place, sur un imageur clinique, de nouveaux protocoles adaptés à l'IRM de l'hélium3 hyperpolarisé et sur leur validation au cours d'études précliniques et cliniques. L’IRM de l’hélium3 hyperpolarisé étant non invasive et non ionisante, elle est bien adaptée à l'utilisation chez l'enfant, dès le plus jeune âge, et aux suivis longitudinaux. Pourtant, les protocoles d’imagerie sont le plus souvent réalisés pendant l’apnée, rendant la technique difficilement applicable chez de jeunes enfants. La première contribution de cette thèse porte sur un protocole de respiration spontanée, sa modélisation et sa validation préclinique, préalables à une application chez des patients non coopératifs. La deuxième étude traite de l'application conjointe de l'IRM proton et hélium3 hyperpolarisé à un modèle de pathologie aiguë chez le lapin, maladie jusqu’à présent non étudiée en IRM de l’hélium3 hyperpolarisé. Enfin, la troisième étude s’intéresse à l’évaluation de la sensibilité de la technique et de l'influence d'une séance de drainage bronchique, chez des enfants atteints de mucoviscidose dont la fonction pulmonaire est asymptomatique. / This work deals with the design, on a clinical scanner, of new protocols for helium3 MRI and with their application to preclinical and clinical studies. Allowing for a virtually unlimited number of acquisitions, helium3 MRI is well adapted for longitudinal or pediatric studies. Acquisitions, however, are mostly performed under breath-hold, precluding the application to non cooperative patients. The first part of this thesis addresses the use of a free-breathing protocol, validated in vivo on rabbit and optimized using a model of gas exchange. A second study tackles the joint use of helium3 and proton MRI to study acute diseases, using a rabbit model of Acute Respiratory Distress Syndrome. Finally, the third study demonstrates the sensitivity of helium3 MRI and evaluates the influence of chest physical therapy on cystic fibrosis children with normal respiratory function.
93

Cloning and characterization of the human coronavirus NL63 nucleocapsid protein

Berry, Michael January 2011 (has links)
<p>The human coronavirus NL63 was discovered in 2004 by a team of researchers in Amsterdam. Since its discovery it has been shown to have worldwide spread and affects mainly children, aged 0-5 years old, the immunocompromised and the elderly. Infection with HCoV-NL63 commonly results in mild upper respiratory tract infections and presents as the common cold, with symptoms including fever, cough, sore throat and rhinorrhoea. Lower respiratory tract findings are less common but may develop into more serious complications including bronchiolitis, pneumonia and croup. The primary function of the HCoV-NL63 nucleocapsid (N) protein is the formation of theprotective ribonucleocapsid core. For this particle to assemble, the N-protein undergoes N-N dimerization and then interacts with viral RNA. Besides the primary structural role of the Nprotein, it is also understood to be involved in viral RNA transcription, translation and replication, including several other physiological functions. The N-protein is also highly antigenic and elicits a strong immune response in infected patients. For this reason the N-protein may serve as a target for the development of diagnostic assays. We have used bioinformatic analysis to analyze the HCoV-NL63 N-protein and compared it to coronavirus N-homologues. This bioinformatic analysis provided the data to generate recombinant clones for expression in a bacterial system. We constructed recombinant clones of the N-protein of SARS-CoV and HCoV-NL63 and synthesized truncated clones corresponding to the N- and C-terminal of the HCoV-NL63 N-protein. These heterologously expressed proteins will serve the basis for several post-expression studies including characterizing the immunogenic epitope of the N-protein as well identifying any antibody crossreactivity between coronavirus species.</p>
94

Expression of Human Coronavirus NL63 and SARS-CoV Nucleocapsid Proteins for antibody production

Mnyamana, Yanga E. January 2012 (has links)
<p>Human Coronaviruses (HCoVs) are found within the family Coronaviridae (genus, Coronavirus) and are enveloped, single-stranded, positive-sense RNA viruses. Infections of humans by&nbsp / coronaviruses are not normally associated with severe diseases. However, the identification of the coronavirus responsible for the outbreak of severe acute respiratory syndrome (SARS-CoV)&nbsp / showed that highly pathogenic coronaviruses can enter the human population. The SARS-CoV epidemic resulted in 8 422 cases with 916 deaths globally (case fatality rate: 10.9%). In 2004 a&nbsp / group 1 Coronavirus, designated Human Coronavirus NL63 (HCoV-NL63), was isolated from a 7 month old Dutch child suffering from bronchiolitis. In addition, HCoV-NL63 causes disease in&nbsp / children (detected in approximately 10% of respiratory tract infections), the elderly and the immunocompromised. This study was designed to express the full length nucleocapsid (N) proteins of&nbsp / HCoV-NL63 and SARS-CoV for antibody production in an animal model. The NL63-N/pFN2A and SARSN/ pFN2A plasmid constructs were used for this study. The presence of the insert on the Flexi &reg / vector was confirmed by restriction endonuclease digest and sequence verification. The sequenced chromatographs obtained from Inqaba Biotec were consistent with sequences from&nbsp / the NCBI Gen_Bank. Proteins were expressed in a KRX Escherichia coli bacterial system and analysed using 15% SDS-PAGE and Western Blotting. Thereafter, GST-tagged proteins were purified&nbsp / ith an affinity column purification system. Purified fusion proteins were subsequently cleaved with Pro-TEV Plus protease, separated on 15% SDS-PAGE gel and stained with Coomassie&nbsp / Brilliant Blue R250. The viral fusion proteins were subsequently used to immunize Balbc mice in order to produce polyclonal antibodies. A direct ELISA was used to analyze and validate the&nbsp / production of polyclonal antibodies by the individual mice. This is a preliminary study for development of diagnostic tools for the detection of HCoV-NL63 from patient samples collected in the&nbsp / Western Cape.</p>
95

Cell- and Cell-based Gene Therapy for Experimental Acute Lung Injury and Sepsis

Mei, Shirley Hsin-Ju 20 January 2009 (has links)
The acute respiratory distress syndrome (ARDS) and its less severe form, acute lung injury (ALI), are among the leading causes of morbidity and mortality in critically ill patients. Commonly induced by conditions associated with severe pulmonary inflammation, ALI results in disruption of the lung alveolar-capillary membrane barrier and resultant pulmonary edema associated with a proteinaceous alveolar exudate. Sepsis is another frequent and often fatal clinical condition for patients in the intensive care unit. It is characterized by a combination of infection and systemic inflammatory response syndrome (SIRS). Current effective treatment strategies for both ALI/ARDS and sepsis are lacking. We first examined the potential therapeutic role of mesenchymal stromal cells (MSCs) alone or together with the vasculoprotective factor, angiopoietin-1 (ANGPT1), for treatment of experimental ALI in mice. MSCs significantly reduced LPS (lipopolysaccharide)-induced pulmonary inflammation, as reflected by cell counts in bronchoalveolar lavage (BAL) fluid and pro-inflammatory cytokine levels in both BAL fluid and lung parenchymal homogenates. More importantly, administration of MSCs transfected with human ANGPT1 plasmid (MSCs-pANGPT1) completely reversed LPS-induced permeability in the lung (i.e., ALI). A follow-up study showed that MSCs remained effective in rescuing mice with LPS-induced ALI; however, the additional benefit from ANGPT1 was no longer observed. To further evaluate MSC-based therapy in a more clinically relevant model of acute injury, the cecal-ligation-and-puncture (CLP) model for sepsis was employed. Our results demonstrated that MSCs can reduce both systemic and pulmonary inflammation, as well as renal and liver dysfunction/injury, as reflected by plasma urea and bilirubin levels, in septic mice. Most notably, MSCs reduced sepsis-associated mortality from 45% to 24%. Our data demonstrate the feasibility and effectiveness of MSC- and MSC-based gene therapy for experimental ALI and sepsis, and provide the basis for the development of an innovative approach for the prevention and treatment of clinical ALI/ARDS and sepsis.
96

Cell- and Cell-based Gene Therapy for Experimental Acute Lung Injury and Sepsis

Mei, Shirley Hsin-Ju 20 January 2009 (has links)
The acute respiratory distress syndrome (ARDS) and its less severe form, acute lung injury (ALI), are among the leading causes of morbidity and mortality in critically ill patients. Commonly induced by conditions associated with severe pulmonary inflammation, ALI results in disruption of the lung alveolar-capillary membrane barrier and resultant pulmonary edema associated with a proteinaceous alveolar exudate. Sepsis is another frequent and often fatal clinical condition for patients in the intensive care unit. It is characterized by a combination of infection and systemic inflammatory response syndrome (SIRS). Current effective treatment strategies for both ALI/ARDS and sepsis are lacking. We first examined the potential therapeutic role of mesenchymal stromal cells (MSCs) alone or together with the vasculoprotective factor, angiopoietin-1 (ANGPT1), for treatment of experimental ALI in mice. MSCs significantly reduced LPS (lipopolysaccharide)-induced pulmonary inflammation, as reflected by cell counts in bronchoalveolar lavage (BAL) fluid and pro-inflammatory cytokine levels in both BAL fluid and lung parenchymal homogenates. More importantly, administration of MSCs transfected with human ANGPT1 plasmid (MSCs-pANGPT1) completely reversed LPS-induced permeability in the lung (i.e., ALI). A follow-up study showed that MSCs remained effective in rescuing mice with LPS-induced ALI; however, the additional benefit from ANGPT1 was no longer observed. To further evaluate MSC-based therapy in a more clinically relevant model of acute injury, the cecal-ligation-and-puncture (CLP) model for sepsis was employed. Our results demonstrated that MSCs can reduce both systemic and pulmonary inflammation, as well as renal and liver dysfunction/injury, as reflected by plasma urea and bilirubin levels, in septic mice. Most notably, MSCs reduced sepsis-associated mortality from 45% to 24%. Our data demonstrate the feasibility and effectiveness of MSC- and MSC-based gene therapy for experimental ALI and sepsis, and provide the basis for the development of an innovative approach for the prevention and treatment of clinical ALI/ARDS and sepsis.
97

Effectiveness of a specific infection control education program for Taiwanese nursing students

Wu, Chia Jung January 2007 (has links)
The purpose of the study The purpose of this research project was to develop and test an educational program for preparing Taiwanese nursing students for clinical practice. Study background The SARS outbreak revealed that health care professionals were ill-prepared for coping with the disease epidemic in terms of the rapid transmission of the infection, the high mortality and morbidity rate among health care workers, and the significant impacts on the public and health care personnel. Frontline nurses were the group at highest risk of becoming infected, as they are the health care personally that provide direct health care to infected patients. However, to date the ability of Taiwanese frontline nurses to respond to such a disease epidemic has not been examined. Study design This research project incorporated a three phase design, presented in the form of two separate studies. A small qualitative exploratory study was undertaken to validate the assumptions emerging from international literature regarding the preparedness nurses in managing an infection outbreak. The information gained was used to construct an infection control education program (Study I). A quasi-experimental design, using pre- and post-tests and experimental and control groups was then used to test the effectiveness of the education intervention (Study II). Participants A purposive sampling technique was used in the qualitative exploratory study, whereby six Taiwanese nurses who had provided direct nursing care to patients with SARS were interviewed. A convenience sampling approach was utilised in the quantitative study, which aimed to test the effectiveness of educational intervention. This, second study, had 175 participants in total, 80 in the experimental group and 95 in the control group. All participants were enrolled in the first semester of their fourth year in a five-year nursing program in two selected junior nursing colleges. The education intervention The purpose-designed standard and additional precautions (SnAP) program was the intervention. The experimental group received a SnAP program which consisted of 16 hours of classes over 16 weeks. The control group received a conventional education program. Data collection and instrument Data were collected at three time points during the study (baseline, four months, six month) using validated instrument. The reliability and validity of the instrument was established in a pilot study with a Taiwanese population prior to the present study. Data analysis t-tests and chi-square analyses were performed to assess any differences across demographic variables and baseline outcome variables between the experimental and control groups. Two-way repeated measures ANOVAs were used to examine the scores of the intervention and control groups across three time points. Results The data revealed that, at six months following the education program, there was a statistically significant improvement in the knowledge (F [2,180] =13.53, p=0.001) and confidence (F [2,94] =4.88, p= 0.01) of infection precautions in the intervention group compared to the control group. Also, the means of knowledge and confidence in intervention group showed a consistently increased across three time points; whereas, the mean of confidence relating infection control management in the control group resulted a drop at time 3. Although the application skills relating to infection control procedures did not show a statistically significant change during this period (F [2, 174] = 2.54, p=0.081), there were minor improvements in these scores at the six-month follow-up assessment. Conclusion The SnAP program had a positive impact on Taiwanese nursing students' readiness for clinical placement and potential outbreak of disease epidemics. Participation increased their knowledge about infection control precautions, their ability to properly use these specific precautions, and their confidence in solving infection-related issues in clinical practice.
98

Evaluation du travail respiratoire dans l'insuffisance respiratoire aigue de l'enfant / Work of breathing assessment in critically ill children

Mortamet, Guillaume 22 January 2018 (has links)
Chez l’enfant, l’insuffisance respiratoire aiguë est responsable de la majeure partie des admissions en soins intensifs. La population pédiatrique étant marquée par une grande hétérogénéité en termes d’âge, de pathologie respiratoire et de maturation pulmonaire, une individualisation de la prise en charge thérapeutique est indispensable. Dans ce contexte, différents outils sont disponibles pour évaluer de manière plus objective le travail respiratoire du patient en insuffisance respiratoire aiguë. Objectifs - Le principal objectif de la thèse est d’évaluer l’intérêt diagnostique et thérapeutique de la mesure du travail respiratoire dans l’insuffisance respiratoire aiguë hypercapnique de l’enfant.Méthodes - Trois principaux outils d’évaluation du travail respiratoire ont été utilisés dans nos travaux : la mesure des pressions œsogastriques, la mesure de l’activité électrique du diaphragme et la mesure de la consommation en oxygène par la calorimétrie.Résultats - Nous avons pu mettre en évidence les intérêts de ces outils de mesure aux différents stades d’évolution de la maladie : (i) à la phase initiale pour indiquer l’initiation d’une ventilation non invasive et pour optimiser ces réglages ; (ii) à la phase d’évolution de la maladie pour évaluer l’interaction patient-ventilateur ; (iii) à la phase de sevrage ventilatoire pour détecter précocement une augmentation du travail respiratoire.Conclusion - Tout au long du processus évolutif de la maladie, la surveillance objective du travail respiratoire peut aider à comprendre les mécanismes de la maladie pulmonaire, optimiser les réglages de l’assistance respiratoire, et adapter les interventions thérapeutiques. / Acute respiratory failure is the leading cause of hospital admissions in the pediatric intensive care unit and is associated with significant morbidity and mortality. Since the pediatric population is characterized by a great heterogeneity in terms of age and respiratory pathology, individualization of therapeutic management is essential. Different minimally invasive methods have been described to assess the patient's work of breathing in acute respiratory failure.Objectives - The main objective of the project was to assess the diagnostic and therapeutic contribution of the measurement of the work of breathing in children with acute hypercapnic respiratory failure.Methods - We used in the present work three tools to assess the work of breathing: oesogastric pressures, electrical activity of the diaphragm monitoring and oxygen consumption measurements.Results - We highlighted how these different methods are valuable during the ICU stay: (i) in the early phase of the disease to initiate or withdraw noninvasive ventilation and to optimize its settings; (ii) in the recovery phase to evaluate the patient-ventilator interaction; (iii) during the weaning process to early detect an increase in work of breathing.Conclusion - Throughout the disease process, the work of breathing assessment can be useful to enhance our understanding of the pathophysiology of lung disease, to optimize mechanical ventilation settings and adapt therapeutic interventions.
99

Prevalência de vírus respiratórios em crianças de creche com sintomas de infecções respiratórias agudas

Bonfim, Caroline Measso do [UNESP] 05 March 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-03-05Bitstream added on 2014-06-13T19:55:51Z : No. of bitstreams: 1 bonfim_cm_me_sjrp.pdf: 483201 bytes, checksum: ee7e5d0928d4f0c7dcb6b57d4216ed16 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / As infecções do trato respiratório estão associadas com mortalidade significativa no mundo inteiro e afetam principalmente crianças menores de cinco anos de idade. A maioria das infecções respiratórias é causada por agentes virais como: Vírus Sincicial Respiratório (RSV), Influenzavírus tipo A e B (FLUA e FLUB), Parainfluenza tipo 1, 2 and 3 (PIV-1, PIV-2 e PIV-3), Rhinovirus (HRV) e Metapneumovirus Humano (hMPV). O conhecimento da epidemiologia e prevalência desses vírus é importante para que metodologias terapêuticas possam ser aplicadas apropriadamente e saber como esses vírus estão circulando. O objetivo deste trabalho foi investigar a incidência de 8 tipos de vírus respiratórios em 279 amostras de aspirado nasofaríngeo obtidas de Julho/2004 a Setembro de 2005 de 120 crianças (73 do sexo masculino e 47 do sexo feminino) com idade entre 0 a 6 anos com sintomas de infecção respiratória aguda. A análise foi realizada pela técnica de RT-PCR e seqüenciamento direto. Nossos resultados mostraram que 27,2% (76/279) das amostras foram positivas para pelo um dos vírus respiratórios, sendo 84,2% (64/76) de Picornavírus, 76,3% (58/76) de Rhinovírus e 7,9% de Enterovírus (6/76), 7,9% (6/76) de RSV, 1,3% (1/76) de hMPV, 2,6% (2/76) de FLUA, 2,6% (2/76) de PIV-1 e 1,3% (1/76) de PIV-2. As infecções repetidas acometeram 29% (22/76) das crianças com infecção respiratória. A maioria das re-infecções, 82% (18/22), foram pelo gênero Rhinovírus. Os sintomas mais freqüentes foram coriza diagnosticada em 89,5% dos casos (68/76) seguido de tosse em 67,1% (51/76). Os Rhinovírus foram detectados em todo o período de estudo, com picos de infecção nos meses de inverno e outono, porém não houve associação significativa entre a presença viral e a sazonalidade. Neste estudo houve prevalência de infecção e re-infecção por Rhinovírus. Portanto, este estudo... / Respiratory tract infections are associated with significant mortality worldwide and affect mostly children under five years of age. Most respiratory infections are caused by viral agents such as: Respiratory Syncytial Virus (RSV), the viruses of Influenza type A and B (FLUA and FLUB), Parainfluenza type 1, 2 and 3 (PIV-1, PIV-2 and PIV-3), Rhinovirus (HRV) and Human Metapneumovirus (hMPV). Knowledge of the epidemiology and prevalence of these viruses is important for therapeutic methods can be applied as appropriate and to know how these viruses are circulating. The aim of this work was to investigate the incidence of 8 types of respiratory viruses in 279 samples of nasopharyngeal aspirated obtained from July/2004 to September/2005 of 120 children (73 male and 47 female) with age between 0 to 6 years with symptoms of acute respiratory infection. The analysis was performed by RT-PCR and direct sequencing. Our results showed that 27,2% (76/279) of samples were positive at least for a type of the respiratory viruses, with 84,2% (64/76) of Picornaviruses, with 76,3% (58/76) of Rhinovírus e 7,9% of Enterovírus (6/76), 7,9% (6/76) of RSV, 1,3% (1/76) of hMPV, 2,6% (2/76) of FLUA, 2,6% (2/76) of PIV-1 and 1,3% (1/76) of PIV-2. The recurrent infections affect 29% (22/76) of children with respiratory infection. Most re-infections, 82% (18/22), were by Rhinovírus genus. The most frequent symptoms were runny nose diagnosed in 89.5% (68/76) followed by cough in 67.1% (51/76). Rhinovírus were detected throughout the study period, with peaks of infection during the winter and autumn, but there was no significant association between viral presence and seasonality. In this study there was prevalence of infection and re-infection by Rhinovírus. Therefore, this study provided better understanding of the circulation of respiratory viruses in a population of day care in the region... (Complete abstract click electronic access below)
100

Efeitos da reposição volêmica com solução salina hipertônica a 3% na resposta inflamatória e na lesão orgânica após choque hemorrágico / Effects of 3% hypertonic saline solution on inflammatory response and end-organ damage after hemorrhagic shock

Rodrigo Vincenzi 17 September 2009 (has links)
INTRODUÇÃO: Recentes estudos avaliam o uso da solução salina hipertônica na concentração de 3% no tratamento de pacientes com traumatismos cranioencefálicos, entretanto, poucos trabalhos têm analisado a sua eficácia no tratamento do choque hemorrágico. O objetivo deste trabalho é avaliar os efeitos do tratamento do choque hemorrágico com a solução salina hipertônica a 3%, analisando principalmente seus possíveis efeitos benéficos na atenuação da resposta inflamatória decorrrente do choque. Para tal, esta solução será comparada a outras duas, amplamente estudadas: a solução salina hipertônica a 7,5% e a solução de Ringer lactato. MÉTODOS: Foram utilizados, neste estudo, 26 ratos Wistar. Os animais foram anestesiados com pentobarbital sódico por via intraperitoneal (50 mg/Kg) e, então, submetidos a um protocolo de choque hemorrágico controlado. Neste protocolo, os animais foram sangrados até que fosse atingida uma pressão arterial média (PAM) de 35 mmHg, em um período de 10 minutos, sendo este nível de PAM mantido por 50 minutos. Ao término deste período de choque, os animais foram randomizados em três grupos para reposição volêmica: reposição com solução de Ringer lactato (grupo RL, n=7), na dose de 33 mL/Kg; reposição com solução salina hipertônica a 3% (grupo SH3%, n=7), na dose de 10 mL/Kg; reposição com solução salina hipertônica a 7,5% (grupo SH7,5%, n=7), na dose de 4 mL/Kg. Após a infusão das soluções, metade do volume de sangue retirado foi reinfundido em todos os animais. Sangue arterial foi coletado para análise de gasometria, lactato, concentração plasmática de sódio e osmolaridade plasmática. Para avaliação da resposta inflamatória, os animais foram sacrificados quatro horas após o início do experimento, sendo obtidas amostras de sangue para determinação das concentrações plasmáticas de interleucina (IL) -6 e fator de necrose tumoral (TNF) -alfa. Amostras de tecido pulmonar e intestinal foram obtidas para avaliação histopatológica de lesão orgânica, sendo as lâminas analisadas por dois patologistas sem conhecimento prévio dos grupos, determinando-se, assim, um escore de lesão baseado em um sistema de pontuação. RESULTADOS: Todos os animais submetidos à reposição volêmica apresentaram valores adequados de PAM ao término do tratamento. Nos animais tratados com as duas concentrações de solução salina hipertônica, a concentração plasmática de sódio e o valor da osmolaridade plasmática foram significativamente maiores, quando comparados aos grupos CT e RL. A concentração plasmática de TNF-alfa foi significativamente maior nos animais tratados com a solução de Ringer lactato, não havendo, para tanto, diferenças estatísticas entre os grupos CT, SH3% e SH7,5%. Em relação a IL-6, não se observou diferenças estatisticamente significantes entre os grupos CT, SH3% e SH7,5%, sendo a concentração plasmática deste mediador inflamatório significativamente elevada no grupo RL, quando comparado ao grupo CT. O escore de lesão pulmonar foi significativamente maior no grupo RL, em comparação aos grupos SH3% e SH7,5% (5,7 ± 0,7, 2,7 ± 0,5, 2,1 ± 0,4, respectivamente). Os animais dos grupos SH3% e SH7,5% apresentaram atenuação da lesão intestinal pós-choque em comparação aos animais do grupo RL (2,3 ± 0,4, 2,0 ± 0,6, 5,9 ± 0,6, respectivamente). CONCLUSÕES: O tratamento do choque hemorrágico com as duas concentrações de solução salina hipertônica resultou em atenuação da resposta inflamatória pós-choque. A solução salina hipertônica a 3% apresentou efeitos metabólicos e imunológicos semelhantes à solução salina hipertônica a 7,5%, sendo ambas superiores em relação aos parâmetros estudados à solução de Ringer lactato. / BACKGROUND: Recent studies have been conducted examining the efficacy of 3% hypertonic saline solution (HSS) in traumatic brain injury; however, few studies have analyzed the effects of 3%HSS during hemorrhagic shock. The aim of this study was to test the potential immunomodulatory benefits of 3%HSS resuscitation over standard fluid resuscitation. METHODS: Wistar rats were bled to a mean arterial pressure (MAP) of 35 mmHg and then randomized in 3 groups: LR (lactated Ringer, 33mL/Kg, n=7), 3%HSS (10mL/Kg, n=7) and 7.5%HSS (4mL/Kg, n=7). Half of the shed blood was infused after fluid resuscitation. Animals who did not undergo shock served as controls (CT,n=5). Four hours after HS, blood was collected for evaluation of tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 by enzyme immunoassay. Lung and intestinal samples were obtained for histopathological analysis. RESULTS: Animals in HSS groups had significantly higher MAP than LR one hour after treatment. Osmolarity and sodium levels were markedly elevated in HSS groups. TNF-alpha and IL-6 levels were similar between CT and HSS groups, but significantly higher in LR (p<0.05). Lung injury score was significantly higher in LR when compared to 7.5%HSS and 3%HSS (5.7 ± 0.7, 2.1 ± 0.4 and 2.7 ± 0.5, respectively). Intestinal injury was attenuated in the 7.5%HSS and 3%HSS groups when compared to LR (2.0 ± 0.6, 2.3 ± 0.4 and 5.9 ± 0.6, respectively). CONCLUSIONS: Small volume resuscitation strategy modulates the inflammatory response and decrease the end-organ damage after HS. 3%HSS provides immunomodulatory and metabolic effects similar to those observed with conventional concentration of HSS.

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