Efeito da heparinização sistêmica em pulmão, intestino delgado e músculo sóleo de suínos submetidos a choque hipovolêmico, clampeamento aórtico e reperfusão
Data
2024-10-04
Autores
Jesus-Silva, Seleno Glauber de 
Orientadores
Fagundes, Djalma José
Tipo
Tese de doutorado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
Objetivos: Avaliar, em modelo experimental com animal de médio porte (suíno), o efeito da anticoagulação com heparina não-fracionada (HNF) em dose terapêutica na isquemia-reperfusão (IR) local (intestino delgado e músculo sóleo) e à distância (pulmão), na vigência de choque hemorrágico (CH) e clampeamento aórtico (CA) prolongado. Métodos: Vinte e um suínos (Sus scrofa, linhagem Large White) foram distribuídos em três grupos: CC (n = 8), submetidos a anestesia geral, monitorização invasiva, laparotomia e isolamento aórtico supracelíaco, CH por 30 min, CA por 1 h e reperfusão visceral por 3 h; CCHep (n = 8), submetidos aos mesmos procedimentos e à heparinização sistêmica com 200 UI/kg in bolus, sendo mantido tempo de coagulação ativado > 200 s durante o CA; e Grupo Simulado (GS; n = 5), submetidos somente à manipulação cirúrgica, sem CH ou CA. Sinais vitais e amostras de sangue para estudo bioquímico foram coletados em várias etapas do experimento. A eutanásia ocorreu ao término do período de reperfusão, quando fragmentos de tecidos foram retirados e processados para coloração de hematoxilina e eosina, e imuno-histoquímica (IIQ) para caspase-3 e BCL-2 por meio de análise semiautomatizada. Resultados: o modelo de IR proposto gerou um distúrbio cardiocirculatório grave, observado pelo aumento do gradiente pressórico carotídeo-femoral (p < 0,001) e lactato (p = 0,001), e diminuição do pH sérico (p = 0,013) nos grupos CC e CCH em relação ao Simulado. O valor médio do escore de lesão tecidual intestinal foi menor para o GS em relação ao grupo CCHep (p = 0,04) apenas. Foi observada uma maior expressão da caspase-3 no intestino delgado do grupo CCHep em relação ao GS e GC (p < 0,001), mas não foram observadas diferenças significativas em relação ao BCL-2. Não foi detectada lesão tecidual ou diferenças na expressão da caspase-3 e BCL-2 no músculo sóleo. Foi observado maior escore de lesão alveolar no grupo CCHep em relação CC (p < 0,01) e menor escore de lesão bronquiolar no grupo CC em relação aos demais (p < 0,001). Foi observada uma menor expressão do BCL-2 no pulmão do grupo CC em relação GS e CCHep (p < 0,001), porém não foram observadas diferenças significantes em relação à caspase-3. Conclusões: o modelo de CH, CA e IR proposto foi eficaz na produção de distúrbio cardiocirculatório grave. Não houve diferenças relevantes nos achados histológicas e imuno-histoquímicos dos tecidos pesquisados. Em consequência, não foi possível estabelecer um efeito consistente da HNF no fenômeno de IR.
Objectives: To evaluate, in an experimental model with a medium-sized animal (swine), the effect of anticoagulation with unfractionated heparin (UFH) at a therapeutic dose on local (small intestine and soleus muscle) and remote (lung) ischemia-reperfusion (IR) in hemorrhagic shock (HS) and prolonged aortic clamping (AC). Methods: Twenty-one pigs (Sus scrofa, Large White lineage) were distributed into three groups: CC (n = 8), subjected to general anesthesia, invasive monitoring, laparotomy, supraceliac aortic isolation, HS for 30 min, AC for 1 h, and visceral reperfusion for 3 h; CCHep (n = 8), subjected to the same procedures and systemic heparinization with 200 IU/kg in bolus, maintaining activated clotting time > 200 s during AC; and Sham Group (SG; n = 5), subjected only to surgical manipulation, without HS or AC. Vital signs and blood samples for biochemical studies were collected at various experimental stages. Euthanasia occurred at the end of the reperfusion period, when tissue fragments were removed and processed for hematoxylin and eosin staining and immunohistochemistry (IIQ) for caspase-3 and BCL-2 through semi-automated analysis. Results: The proposed IR model provoked a severe cardiocirculatory disorder, observed by an increase in the carotid-femoral pressure gradient (p < 0.001) and lactate (p = 0.001), and a decrease in serum pH (p = 0.013) in the CC and CCHep groups in relation to the SG. The mean value of the intestinal tecidual lesion score was lower in the SG than in the CCHep group (p = 0.04). A higher expression of caspase-3 was observed in the small intestine of the CCHep group in relation to SG and CC (p < 0.001), but no significant differences were observed related to BCL-2. No tecidual injury or differences in caspase-3 and BCL-2 expression were detected in the soleus muscle. An increased histological injury score for the alveoli was observed in the CCHep group compared with the CC (p < 0.01), and a lower bronchiolar lesion score was observed in the CC group compared with the others (p < 0.001). A lower expression of BCL-2 was observed in the lungs of the CC group compared with SG and CCHep (p < 0.001), but no differences were observed related to caspase-3. Conclusions: The proposed HS, AC, and IR model was effective in creating a severe cardiocirculatory disorder. No significant differences were observed in the histological and immunohistochemical findings of the tissues studied. As a result, it was not possible to establish a consistent effect of UFH on the IR phenomenon.
Objectives: To evaluate, in an experimental model with a medium-sized animal (swine), the effect of anticoagulation with unfractionated heparin (UFH) at a therapeutic dose on local (small intestine and soleus muscle) and remote (lung) ischemia-reperfusion (IR) in hemorrhagic shock (HS) and prolonged aortic clamping (AC). Methods: Twenty-one pigs (Sus scrofa, Large White lineage) were distributed into three groups: CC (n = 8), subjected to general anesthesia, invasive monitoring, laparotomy, supraceliac aortic isolation, HS for 30 min, AC for 1 h, and visceral reperfusion for 3 h; CCHep (n = 8), subjected to the same procedures and systemic heparinization with 200 IU/kg in bolus, maintaining activated clotting time > 200 s during AC; and Sham Group (SG; n = 5), subjected only to surgical manipulation, without HS or AC. Vital signs and blood samples for biochemical studies were collected at various experimental stages. Euthanasia occurred at the end of the reperfusion period, when tissue fragments were removed and processed for hematoxylin and eosin staining and immunohistochemistry (IIQ) for caspase-3 and BCL-2 through semi-automated analysis. Results: The proposed IR model provoked a severe cardiocirculatory disorder, observed by an increase in the carotid-femoral pressure gradient (p < 0.001) and lactate (p = 0.001), and a decrease in serum pH (p = 0.013) in the CC and CCHep groups in relation to the SG. The mean value of the intestinal tecidual lesion score was lower in the SG than in the CCHep group (p = 0.04). A higher expression of caspase-3 was observed in the small intestine of the CCHep group in relation to SG and CC (p < 0.001), but no significant differences were observed related to BCL-2. No tecidual injury or differences in caspase-3 and BCL-2 expression were detected in the soleus muscle. An increased histological injury score for the alveoli was observed in the CCHep group compared with the CC (p < 0.01), and a lower bronchiolar lesion score was observed in the CC group compared with the others (p < 0.001). A lower expression of BCL-2 was observed in the lungs of the CC group compared with SG and CCHep (p < 0.001), but no differences were observed related to caspase-3. Conclusions: The proposed HS, AC, and IR model was effective in creating a severe cardiocirculatory disorder. No significant differences were observed in the histological and immunohistochemical findings of the tissues studied. As a result, it was not possible to establish a consistent effect of UFH on the IR phenomenon.
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Citação
JESUS-SILVA, Seleno Glauber de. Efeito da heparinização sistêmica em pulmão, intestino delgado e músculo sóleo de suínos submetidos a choque hipovolêmico, clampeamento aórtico e reperfusão. 2024. 109 f. Tese (Doutorado em Ciência Cirurgica Interdisciplinar) - Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP), São Paulo; 2024.