Estudo das alterações funcionais e morfológicas pulmonares em modelo animal de pneumoperitônio

• Autor(a) principal: Brandão, Julio Cezar Mendes [UNIFESP]
• Data de Publicação: 2017
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UNIFESP
• Texto Completo: https://sucupira.capes.gov.br/sucupira/public/consultas/coleta/trabalhoConclusao/viewTrabalhoConclusao.jsf?popup=true&id_trabalho=4542622; https://repositorio.unifesp.br/handle/11600/50796
• topic: Pneumoperitoneum; Cytokines; Oxidative stress; Pulmonary injury; Laparoscopy; Experimental; Models, animal; Rats; Pneumoperitônio; Citocinas; Estresse oxidativo; Lesão Pulmonar; Laparoscopia; Experimental; Modelos animais; Ratos

Study of functional and morphological pulmonary alterations in an animal model of pneumoperiton. Background: Laparoscopic surgeries require pneumoperitoneum achieved by pressure-controlled insufflation of carbon dioxide into peritoneal cavity. This can change the respiratory mechanics and promotes an oxidative stress. We aimed to assess the effect of different intra-abdominal pressures (IAP) from the pneumoperitoneum in a ventilated rat model with normal lungs. Methods: The animals (n=48) were allocated randomly into 6 groups: Sham group, group without pneumoperitoneum; IAP5 mmHg; IAP8 mmHg; IAP10 mmHg; IAP12 mmHg and IAP14 mmHg. All animals were ventilated during 60 minutes with VT 5 mL/kg, PEEP 2 cmH2O, FiO2 35% and RR 60- 70 bpm. At the end of the experiment the animals were euthanatized and the lungs were removed for analysis. We performed lipid peroxidation, myeloperoxidase activity, cytokines measurements, and histopathologic analysis. Results: The Sham group was lower when compared with other groups in all analysis. TNF-alpha: IAP8 (5.73 pg/mL) was lower when compared with IAP12 (6.32 pg/mL) and IAP14 (7.56 pg/mL) (p<0.001). IAP 12 was lower when compared to IAP14 (p<0.001). IL-6: IAP8 (8.23 pg/mL) was lower when compared to IAP10 (8.91 pg/mL) (p<0.05). IAP10 was lower when compared to IAP12 (9.74 pg/mL) (p<0.01) and to IAP14 (14.57 pg/mL) (p<0.001). IAP12 was lower when compared to IAP14 (p<0.001). Lipid peroxidation: IAP8 was lower when compared to IAP10 (p<0.001), IAP10 was lower when compared to IAP12 (p<0.01). IAP12 was lower when compared to IAP14 (p<0.001). MPO activity: IAP8 (8.23 mU/mL) was lower when compared to IAP10 (8.91 mU/mL) (p<0.05). IAP10 was lower when compared to IAP12 (9.74 mU/mL) (p<0.01), and IAP12 was lower when compared to IAP14 (14.57 mU/mL) (p<0.001). Histological: The tissues from IAP8 rats exhibited low architecture alveolar damage, augment of alveolar septae and neutrophil infiltration, whereas IAP10 and IAP12 groups exhibited alteration in architecture alveolar with septal rupture edema and neutrophil infiltration and the IPA14 exhibited severe septal rupture, edema, diffuse bleeding and neutrophil infiltration. Conclusions: These data demonstrated histological growing changes according to the increase of the intraperitoneal pressure. The biochemical and inflammatory analysis demonstrated increase in the groups with higher pressure. Those findings suggest that the lower pressure protects the lungs from injury after pneumoperitoneum.