Effects of non-muscle myosin Ⅱ silenced bone marrow-derived mesenchymal stem cells transplantation on lung extracellular matrix in rats after endotoxin/lipopolysaccharide-induced acute lung injury / 中华烧伤杂志

Objective: To investigate the effects of non-muscle myosin Ⅱ (NMⅡ) gene silenced bone marrow-derived mesenchymal stem cells (BMMSCs) on pulmonary extracellular matrix (ECM) and fibrosis in rats with acute lung injury (ALI) induced by endotoxin/lipopolysaccharide (LPS). Methods: The experimental research methods were adopted. Cells from femur and tibial bone marrow cavity of four one-week-old male Sprague-Dawley rats were identified as BMMSCs by flow cytometry, and the third passage of BMMSCs were used in the following experiments. The cells were divided into NMⅡ silenced group transfected with pHBLV-U6-ZsGreen-Puro plasmid containing small interference RNA sequence of NMⅡ gene, vector group transfected with empty plasmid, and blank control group without any treatment, and the protein expression of NMⅡ at 72 h after intervention was detected by Western blotting (n=3). The morphology of cells was observed by an inverted phase contrast microscope and cells labeled with chloromethylbenzoine (CM-DiⅠ) in vitro were observed by an inverted fluorescence microscope. Twenty 4-week-old male Sprague-Dawley rats were divided into blank control group, ALI alone group, ALI+BMMSC group, and ALI+NMⅡ silenced BMMSC group according to the random number table, with 5 rats in each group. Rats in blank control group were not treated, and rats in the other 3 groups were given LPS to induce ALI. Immediately after modeling, rats in ALI alone group were injected with 1 mL normal saline via tail vein, rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group were injected with 1×107/mL BMMSCs and NMⅡ gene silenced BMMSCs of 1 mL labelled with CM-DiⅠ via tail vein, and rats in blank control group were injected with 1 mL normal saline via tail vein at the same time point, respectively. At 24 h after intervention, the lung tissue was collected to observe intrapulmonary homing of the BMMSCs by an inverted fluorescence microscope. Lung tissue was collected at 24 h, in 1 week, and in 2 weeks after intervention to observe pulmonary inflammation by hematoxylin eosin staining and to observe pulmonary fibrosis by Masson staining, and the pulmonary fibrosis in 2 weeks after intervention was scored by modified Ashcroft score (n=5). The content of α-smooth muscle actin (α-SMA), matrix metalloproteinase 2 (MMP-2), and MMP-9 was detected by immunohistochemistry in 2 weeks after intervention (n=3), the activity of superoxide dismutase (SOD), malondialdehyde, myeloperoxidase (MPO) was detected by enzyme-linked immunosorbent assay at 24 h after intervention (n=3), and the protein expressions of CD11b and epidermal growth factor like module containing mucin like hormone receptor 1 (EMR1) in 1 week after intervention were detected by immunofluorescence staining (n=3). Data were statistically analyzed with one-way analysis of variance, Bonferroni method, and Kruskal-Wallis H test. Results: At 72 h after intervention, the NMⅡprotein expression of cells in NMⅡ silenced group was significantly lower than those in blank control group and vector group (with P values <0.01). BMMSCs were in long spindle shape and grew in cluster shaped like vortexes, which were labelled with CM-DiⅠ successfully in vitro. At 24 h after intervention, cell homing in lung of rats in ALI+NMⅡ silenced BMMSC group was more pronounced than that in ALI+BMMSC group, while no CM-DiⅠ-labelled BMMSCs were observed in lung of rats in blank control group and ALI alone group. There was no obvious inflammatory cell infiltration in lung tissue of rats in blank control group at all time points, while inflammatory cell infiltration in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group was significantly less than that in ALI alone group at 24 h after intervention, and alveolar wall turned to be thinner and a small amount of congestion in local lung tissue appeared in rats of the two groups in 1 week and 2 weeks after intervention. In 1 week and 2 weeks after intervention, collagen fiber deposition in lung tissue of rats in ALI alone group, ALI+BMMSC group, and ALI+NMⅡ silenced BMMSC group was significantly aggravated compared with that in blank control group, while collagen fiber deposition in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group was significantly improved compared with that in ALI alone group. In 2 weeks after intervention, modified Ashcroft scores for pulmonary fibrosis of rats in ALI alone group, ALI+BMMSC group, and ALI+NMⅡ silenced BMMSC group were 2.36±0.22, 1.62±0.16, 1.06±0.26, respectively, significantly higher than 0.30±0.21 in blank control group (P<0.01). Modified Ashcroft scores for pulmonary fibrosis of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group were significantly lower than that in ALI alone group (P<0.01), and modified Ashcroft score for pulmonary fibrosis of rats in ALI+NMⅡ silenced BMMSC group was significantly lower than that in ALI+BMMSC group (P<0.01). In 2 weeks after intervention, the content of α-SMA in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group were significantly decreased compared with that in ALI alone group (P<0.05 or P<0.01). The content of MMP-2 in lung tissue of rats in the 4 groups was similar (P>0.05). The content of MMP-9 in lung tissue of rats in ALI alone group was significantly increased compared with that in blank control group (P<0.01), and the content of MMP-9 in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group was significantly decreased compared with that in ALI alone group (P<0.01). At 24 h after intervention, the activity of malondialdehyde, SOD, and MPO in lung tissue of rats in ALI alone group, ALI+BMMSC group, and ALI+NMⅡ silenced BMMSC group were significantly increased compared with that in blank control group (P<0.01), the activity of malondialdehyde in lung tissue of rats in ALI+NMⅡ silenced BMMSC group and the activity of SOD in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group were significantly increased compared with that in ALI alone group (P<0.05 or P<0.01), and the activity of SOD in lung tissue of rats in ALI+NMⅡ silenced BMMSC group was significantly decreased compared with that in ALI+BMMSC group (P<0.01). The activity of MPO in lung tissue of rats in ALI+BMMSC group and ALI+NMⅡ silenced BMMSC group was significantly decreased compared with that in ALI alone group (P<0.01), and the activity of MPO in lung tissue of rats in ALI+NMⅡ silenced BMMSC group was significantly decreased compared with that in ALI+BMMSC group (P<0.01). In 1 week after intervention, the protein expression of CD11b in lung tissue of rats in ALI+NMⅡ silenced BMMSC group was significantly increased compared with those in the other three groups (P<0.05 or P<0.01), while the protein expressions of EMR1 in lung tissue of rats in the four groups were similar (P>0.05). Conclusions: Transplantation of NMⅡ gene silenced BMMSCs can significantly improve the activity of ECM components in the lung tissue in LPS-induced ALI rats, remodel its integrity, and enhance its antioxidant capacity, and alleviate lung injury and pulmonary fibrosis.

Verification of the Effects of Red Light-emitting Diode Therapy on Acute Lung Injury in a Sepsis Model in Rats

Abstract The aim of this study was to evaluate the in vivo response of red light-emitting diode (LED) on acute lung injury (ALI) in a sepsis model in rats. Twenty rats were randomly allocated into two experimental groups (n=10): Control Sepsis Group (CS); sepsis and red LED group (SRL). The anterior region of the trachea and ventral regions of the chest (below the ribs), bilaterally were irradiated daily for two consecutive days, starting immediately after the surgery using red (630 nm) LED. The histological results showed that in red LED treated group presented a modulation of the lung inflammatory process, less intense alveolar septum thickening and decrease of the inflammatory cells. Moreover, LED significantly reduced the lung injury score and increased interleukin type 10 (IL-10) protein expression compared SG. These results suggest that LED was efficient in attenuating ALI in a sepsis model in rats by reducing inflammatory cells into lung tissue and enhancing the anti-inflammatory cytokine production.

Electroacupuncture protects septic rats from acute lung injury through the JAK1/STAT3 pathway / 南方医科大学学报

OBJECTIVE@#To explore the protective effect of electroacupuncture against acute lung injury (ALI) in septic rats and explore the mechanism.@*METHODS@#Sixty male SD rats were randomly divided into cecal ligation and puncture (CLP)-induced sepsis group (@*RESULTS@#Compared with those in the sham operation group, the rats in ALI group showed obvious lung pathologies with significantly increased lung W/D ratio (@*CONCLUSIONS@#Electroacupuncture can inhibit the release of inflammatory mediators and cell apoptosis via the JAK1/STAT3 pathway to reduce lung injuries in septic rats.

Comparação entre ventilação mecânica convencional protetora e ventilação oscilatória de alta frequência associada à posição prona / Comparison between conventional protective mechanical ventilation and high-frequency oscillatory ventilation associated with the prone position

RESUMO Objetivo: Comparar os efeitos da ventilação oscilatória de alta frequência e da ventilação mecânica convencional protetora associadas à posição prona quanto à oxigenação, à histologia e ao dano oxidativo pulmonar em modelo experimental de lesão pulmonar aguda. Métodos: Foram instrumentados com traqueostomia, acessos vasculares e ventilados mecanicamente 45 coelhos. A lesão pulmonar aguda foi induzida por infusão traqueal de salina aquecida. Foram formados três grupos experimentais: animais sadios + ventilação mecânica convencional protetora, em posição supina (Grupo Controle; n = 15); animais com lesão pulmonar aguda + ventilação mecânica convencional protetora, posição prona (GVMC; n = 15); animais com lesão pulmonar aguda + ventilação oscilatória de alta frequência, posição prona (GVAF; n = 15). Após 10 minutos do início da ventilação específica de cada grupo, foi coletada gasometria arterial, sendo este momento denominado tempo zero, após o qual o animal foi colocado em posição prona, permanecendo assim por 4 horas. O estresse oxidativo foi avaliado pelo método de capacidade antioxidante total. A lesão tecidual pulmonar foi determinada por escore histopatológico. O nível de significância adotado foi de 5%. Resultados: Ambos os grupos com lesão pulmonar aguda apresentaram piora da oxigenação após a indução da lesão comparados ao Grupo Controle. Após 4 horas, houve melhora significante da oxigenação no grupo GVAF comparado ao GVMC. A análise da capacidade antioxidante total no plasma mostrou maior proteção no GVAF. O GVAF apresentou menor escore de lesão histopatológica no tecido pulmonar que o GVMC. Conclusão: A ventilação oscilatória de alta frequência, associada à posição prona, melhora a oxigenação, e atenua o dano oxidativo e a lesão pulmonar histopatológica, comparada com ventilação mecânica convencional protetora.

ABSTRACT Objective: To compare the effects of high-frequency oscillatory ventilation and conventional protective mechanical ventilation associated with the prone position on oxygenation, histology and pulmonary oxidative damage in an experimental model of acute lung injury. Methods: Forty-five rabbits with tracheostomy and vascular access were underwent mechanical ventilation. Acute lung injury was induced by tracheal infusion of warm saline. Three experimental groups were formed: healthy animals + conventional protective mechanical ventilation, supine position (Control Group; n = 15); animals with acute lung injury + conventional protective mechanical ventilation, prone position (CMVG; n = 15); and animals with acute lung injury + high-frequency oscillatory ventilation, prone position (HFOG; n = 15). Ten minutes after the beginning of the specific ventilation of each group, arterial gasometry was collected, with this timepoint being called time zero, after which the animal was placed in prone position and remained in this position for 4 hours. Oxidative stress was evaluated by the total antioxidant performance assay. Pulmonary tissue injury was determined by histopathological score. The level of significance was 5%. Results: Both groups with acute lung injury showed worsening of oxygenation after induction of injury compared with the Control Group. After 4 hours, there was a significant improvement in oxygenation in the HFOG group compared with CMVG. Analysis of total antioxidant performance in plasma showed greater protection in HFOG. HFOG had a lower histopathological lesion score in lung tissue than CMVG. Conclusion: High-frequency oscillatory ventilation, associated with prone position, improves oxygenation and attenuates oxidative damage and histopathological lung injury compared with conventional protective mechanical ventilation.

Validation of the Portuguese version of the Evidence-Based Practice Questionnaire / Validação da versão portuguesa do Questionário de Eficácia Clínica e Prática Baseada em Evidências / Validación de la versión portuguesa del Cuestionario de Eficacia Clínica y Práctica Basada en Evidencias

OBJECTIVES: to describe the process of translation and linguistic and cultural validation of the Evidence Based Practice Questionnaire for the Portuguese context: Questionário de Eficácia Clínica e Prática Baseada em Evidências (QECPBE). METHOD: a methodological and cross-sectional study was developed. The translation and back translation was performed according to traditional standards. Principal Components Analysis with orthogonal rotation according to the Varimax method was used to verify the QECPBE's psychometric characteristics, followed by confirmatory factor analysis. Internal consistency was determined by Cronbach's alpha. Data were collected between December 2013 and February 2014. RESULTS: 358 nurses delivering care in a hospital facility in North of Portugal participated in the study. QECPBE contains 20 items and three subscales: Practice (α=0.74); Attitudes (α=0.75); Knowledge/Skills and Competencies (α=0.95), presenting an overall internal consistency of α=0.74. The tested model explained 55.86% of the variance and presented good fit: χ2(167)=520.009; p = 0.0001; χ2df=3.114; CFI=0.908; GFI=0.865; PCFI=0.798; PGFI=0.678; RMSEA=0.077 (CI90%=0.07-0.08). CONCLUSION: confirmatory factor analysis revealed the questionnaire is valid and appropriate to be used in the studied context. .

OBJETIVOS: descrever o processo de tradução e validação linguística e cultural para o contexto português do Questionário de Eficácia Clínica e Prática Baseada em Evidências (QECPBE). MÉTODO: desenvolveu-se um estudo metodológico e transversal. Foi efetuada tradução e retroversão, de acordo com os padrões usuais. Na determinação das características psicométricas do QECPBE utilizou-se a Análise de Componentes Principais com rotação ortogonal, segundo o método Varimax, seguida de análise fatorial confirmatória. A consistência interna foi determinada pelo valor alfa de Cronbach. A coleta de dados ocorreu entre dezembro de 2013 e fevereiro de 2014. RESULTADOS: participaram 358 enfermeiros que exercem a prática clínica num centro hospitalar do norte de Portugal. O QECPBE apresenta 20 itens e três subescalas: Práticas (α=0,74); Atitudes (α=0,75); Conhecimentos/Habilidades e Competências (α=0,95), apresentando consistência interna global de α=0,74. No modelo testado obteve-se variância explicada de 55,86%. O modelo demonstrou um bom ajuste: χ2(167)=520,009; p=0,0001; χ2df=3,114; CFI=0,908; GFI=0,865; PCFI=0,798; PGFI=0,678; RMSEA=0,077 (IC90%=0,07-0,08). CONCLUSÃO: através da análise fatorial confirmatória realizada demonstrou-se que o questionário é válido e adequado para utilização no contexto estudado. .

OBJETIVOS: describir el proceso de traducción y validación lingüística y cultural para el contexto portugués del Cuestionario de Eficacia Clínica y Práctica Basada en Evidencias (CECPBE). MÉTODO: se desarrolló un estudio metodológico y transversal. Fue efectuada traducción y retroversión de acuerdo con los estándares usuales. En la determinación de las características psicométricas del CECPBE se utilizó el Análisis de Componentes Principales con rotación ortogonal, según el método Varimax, seguido por análisis factorial confirmatorio. La consistencia interna fue determinada por el valor alfa de Cronbach. La recolección de datos ocurrió entre diciembre de 2013 y febrero de 2014. RESULTADOS: participaron 358 enfermeros que ejercían la práctica clínica en un centro hospitalario en el norte de Portugal. El CECPBE presenta 20 ítems y tres subescalas: Prácticas (α=0,74); Actitudes (α=0,75); Conocimientos/Habilidades y Competencias (α=0,95), presentando consistencia interna global de α=0,74. En el modelo probado se obtuvo variancia explicada de 55,86%. El modelo demostró un buen ajuste: χ2(167)=520,009; p=0,0001; χ2df=3,114; CFI=0,908; GFI=0,865; PCFI=0,798; PGFI = 0,678; RMSEA = 0,077 (IC90%=0,07-0,08). CONCLUSIÓN: a través del análisis factorial confirmatorio se demostró que el cuestionario es válido y adecuado para utilización en el contexto estudiado. .

Postperfusion lung syndrome: physiopathology and therapeutic options / Síndrome pós-perfusão pulmonar: fisiopatologia e opções terapêuticas

Postperfusion lung syndrome is rare but can be lethal. The underlying mechanism remains uncertain but triggering inflammatory cascades have become an accepted etiology. A better understanding of the pathophysiology and the roles of inflammatory mediators in the development of the syndrome is imperative in the determination of therapeutic options and promotion of patients' prognosis and survival. Postperfusion lung syndrome is similar to adult respiratory distress syndrome in clinical features, diagnostic approaches and management strategies. However, the etiologies and predisposing risk factors may differ between each other. The prognosis of the postperfusion lung syndrome can be poorer in comparison to acute respiratory distress syndrome due to the secondary multiple organ failure and triple acid-base imbalance. Current management strategies are focusing on attenuating inflammatory responses and preventing from pulmonary ischemia-reperfusion injury. Choices of cardiopulmonary bypass circuit and apparatus, innovative cardiopulmonary bypass techniques, modified surgical maneuvers and several pharmaceutical agents can be potential preventive strategies for acute lung injury during cardiopulmonary bypass.

Síndrome pós-perfusão pulmonar é rara, mas pode ser letal. O mecanismo subjacente permanece incerto, mas desencadear cascatas inflamatórias tornou-se uma etiologia aceita. É imperativo uma melhor compreensão da fisiopatologia e os papéis de mediadores inflamatórios no desenvolvimento da síndrome na determinação de opções terapêuticas e de promoção do prognóstico e sobrevida dos pacientes. Síndrome pós-perfusão pulmonar é semelhante à síndrome da angústia respiratória do adulto em características clínicas, métodos diagnósticos e estratégias de gestão. No entanto, as etiologias e fatores de risco predisponentes podem ser diferentes entre si. O prognóstico da síndrome pós-perfusão pulmonar pode ser mais pobres em comparação com síndrome da angústia respiratória aguda, devido à falência de múltiplos órgãos secundária e desequilíbrio ácido-base triplo. Estratégias de gestão atuais centram-se em atenuar reações inflamatórias e impedir lesão pulmonar de isquemia-reperfusão. Escolhas do circuito de circulação extracorpórea e aparelhos, técnicas inovadoras de circulação extracorpórea, manobras cirúrgicas modificadas e vários agentes farmacêuticos podem ser potenciais estratégias preventivas para lesão pulmonar aguda durante a circulação extracorpórea.

Análise comparativa entre a manobra de recrutamento alveolar e a técnica de breath stacking em pacientes com lesão pulmonar aguda / Comparative analysis between the alveolar recruitment maneuver and breath stacking technique in patients with acute lung injury

Objetivo: Comparar a eficácia da manobra de recrutamento alveolar e a técnica de breath stacking, na mecânica pulmonar e na troca gasosa, em pacientes com lesão pulmonar aguda. Métodos: Trinta pacientes foram distribuídos em dois grupos: Grupo 1 - breath stacking e Grupo 2 - manobra de recrutamento alveolar. Após receberem atendimento de fisioterapia convencional, todos os pacientes receberam ambos os tratamentos, com intervalo de 1 dia entre eles. No primeiro grupo foi aplicada primeiramente a técnica de breath stacking e, posteriormente, a manobra de recrutamento alveolar. Já os pacientes do segundo Grupo 2 foram submetidos inicialmente ao recrutamento alveolar e, após, a técnica de breath stacking. Foram avaliadas as medidas de complacência pulmonar e de resistência de vias aéreas antes e após a aplicação de ambas as técnicas. Foram coletadas gasometrias arteriais pré e pós-técnicas para avaliar a oxigenação e a troca gasosa. Resultados: Ambos os grupos apresentaram aumento significativo da complacência estática após breath stacking (p=0,021) e recrutamento alveolar (p=0,03), mas não houve diferença entre eles (p=0,95). A complacência dinâmica não aumentou para os grupos breath stacking (p=0,22) e recrutamento alveolar (p=0,074), sem diferença entre os grupos (p=0,11). A resistência de vias aéreas não diminuiu para ambos os grupos: breath stacking (p=0,91) e recrutamento alveolar (0,82), sem diferença entre os grupos p=0,39. A pressão parcial de oxigênio aumentou significantemente após breath stacking (p=0,013) e recrutamento alveolar (p=0,04); mas entre os grupos não houve diferença (p=0,073). A diferença alvéolo arterial de O2 diminuiu para ambos os grupos após intervenções breath stacking (p=0,025) ...

Objective: To compare the effectiveness of the alveolar recruitment maneuver and the breath stacking technique with respect to lung mechanics and gas exchange in patients with acute lung injury. Methods: Thirty patients were distributed into two groups: Group 1 - breath stacking; and Group 2 - alveolar recruitment maneuver. After undergoing conventional physical therapy, all patients received both treatments with an interval of 1 day between them. In the first group, the breath stacking technique was used initially, and subsequently, the alveolar recruitment maneuver was applied. Group 2 patients were initially subjected to alveolar recruitment, followed by the breath stacking technique. Measurements of lung compliance and airway resistance were evaluated before and after the use of both techniques. Gas analyses were collected before and after the techniques were used to evaluate oxygenation and gas exchange. Results: Both groups had a significant increase in static compliance after breath stacking (p=0.021) and alveolar recruitment (p=0.03), but with no significant differences between the groups (p=0.95). The dynamic compliance did not increase for the breath stacking (p=0.22) and alveolar recruitment (p=0.074) groups, with no significant difference between the groups (p=0.11). The airway resistance did not decrease for either groups, i.e., breath stacking (p=0.91) and alveolar recruitment (p=0.82), with no significant difference between the groups (p=0.39). The partial pressure of oxygen increased significantly after breath stacking (p=0.013) and alveolar recruitment (p=0.04), but there was no significant difference between the groups (p=0.073). The alveolar-arterial O2 difference decreased for both groups after the breath stacking (p=0.025) and alveolar recruitment (p=0.03) interventions, and there was no significant difference between the groups (p=0.81). Conclusion: Our data suggest that the breath stacking and alveolar ...

Liquid Ventilation

Mammals have lungs to breathe air and they have no gills to breath liquids. When the surface tension at the air-liquid interface of the lung increases, as in acute lung injury, scientists started to think about filling the lung with fluid instead of air to reduce the surface tension and facilitate ventilation. Liquid ventilation [LV] is a technique of mechanical ventilation in which the lungs are insufflated with an oxygenated perfluorochemical liquid rather than an oxygen-containing gas mixture. The use of perfluorochemicals, rather than nitrogen, as the inert carrier of oxygen and carbon dioxide offers a number of theoretical advantages for the treatment of acute lung injury. In addition, there are non-respiratory applications with expanding potential including pulmonary drug delivery and radiographic imaging. The potential for multiple clinical applications for liquid-assisted ventilation will be clarified and optimized in future

Aspectos histomorfológicos e respiratórios em modelo de lesão pulmonar aguda por sepse em ratos tratados com pentoxifilina / Histomorphologic and respiratory aspects of acute lung injury in rats induced by experimental sepsis and under pentoxifylline treatment

OBJETIVO: Analisar as alterações histomorfológicas e respiratórias em modelo de lesão pulmonar aguda por sepse em ratos tratados com pentoxifilina. MÉTODOS: Foram utilizados 15 ratos adultos distribuídos em três grupos (n=5, por grupo), assim constituídos: GC - receberam apenas ventilação mecânica; GS - Animais sépticos tratados com solução salina e mecanicamente ventilados; GS+PTX - Animais sépticos, com infusão de pentoxifilina e mecanicamente ventilados. Todos os animais foram ventilados por um período de 180 minutos. Ao final deste período, foram avaliadas variáveis gasométricas (gasometria arterial), gravimétricas (relação peso úmido/peso seco), concentração de proteínas totais no lavado broncoalveolar e histomorfométricas (espessura dos septos alveolares). Os dados obtidos foram submetidos a análise estatística (P < 0,05) RESULTADOS: A pressão parcial de oxigênio ao final do experimento mostrou-se elevada no grupo GS+PTX (460,0 ± 38,2 mmHg) em relação ao grupo GS (336,0 ± 14,6 mmHg) (P < 0,05). No grupo GS, a concentração de proteínas no lavado broncoalveolar encontrou-se aumentada em relação aos demais grupos; no entanto, se mostrou atenuada após a administração de pentoxifilina. Notamos, pela morfologia em todos os grupos avaliados, vasodilatação nos septos alveolares e no grupo S alguns alvéolos apresentaram-se repletos de macrófagos. Estes aspectos foram atenuados no GS+PTX. A espessura dos septos alveolares mostrou uma significante redução no grupo GS+PTX quando comparado com o grupo GS (P < 0,05). CONCLUSÃO: A pentoxifilina restabelece a oxigenação e reduz os efeitos deletérios do processo de sepse em associação à ventilação mecânica com baixo volume corrente.

OBJECTIVE: Respiratory repercussion on acute lung injury in a model of induced sepsis intraperitoneally. METHODS: Fifteen animals taken at random were submitted to adult male Wistar rats. The rats were randomly divided into 3 groups (n=15): Group C - control group received only mechanical ventilation; Group S - rats received live Escherichia coli (E. coli) intraperitoneally (septic) and after 6 hours they were treated with normal saline infusion and ventilated with a low tidal volume. Group S+PTX - rats received live Escherichia coli intraperitoneally (septic) and after 6 hours they were treated with pentoxifylline (PTX) infusion and ventilated with a low tidal volume. All animals were ventilated during 180 minutes. We analyzed the arterial blood gases, gravimetric indices and histomorphometric analysis. RESULTS: Blood gases, wet to dry ratios, and total protein concentrations in the bronchoalveolar lavage were analyzed in all experimental groups. In the end of the experiment the partial pressure of oxygen was higher in the GS+PTX (460,0 ± 38,2 mmHg) compared with GS (336,0 ± 14,6 mmHg). Pentoxifylline with low tidal volume attenuated significantly total protein in the bronchoalveolar lavage. The septal diameter was significantly reduced in the group GS compared with group GS+PTX (P < 0,05). CONCLUSIONS:The pentoxifylline ameliorated the oxygenation and decreased the deleterious effects of sepsis in the associated mechanical ventilation.