Isquemia e reperfusão hepatica total em condições de normalidade e sob estado de choque hemorragico controlado : efeitos no sequestro de neutrofilos no ileo terminal e colon sigmoide do rato

AUTOR(ES)
DATA DE PUBLICAÇÃO

2001

RESUMO

The trauma is one of the main causes of death on the population, ranking the third place if considered all ages and the first up to the age of 44. Among these causes, the liver represents the most frequently hit organ in abdominal trauma.This way, the patients victims of severe hepatic injuries, due to hemorrhagic shock, can evolve to a systemic inflammatory response syndrome resultingin multiple organs and systems insufficiency. In these cases,the surgical treatment principie is to stop the bleeding by temporary portal triad occlusion, maneuver described by Pringle in 1908. Although practical and effective, this procedure provokes total ischemia of the tiver and may lead to important alterations on the anatomic structure of the organ, worsening the reperfusion phase by releasing substances that trigger the inflammatory response and migration of neutrophils to the distant tissues. This way, the objective of this experimental work was to study the effects of total hepatic ischemia and reperfusion, under normal conditions and under controlled hemorrhagic shock state, on the accumulation of neutrophils in the gut of rat. A total of 32 adult male Wistar rats, were divided into four groups of eight animaiseach. 1) Shamgroup (anesthesia+ laparotomy+ observationf or 60 min.); 2) Shock group (anesthesia+ hemorrhagicshock for 20 min.+ volemic resuscitation + reperfusion for 60 min.); Pringle group (anesthesia + hepatic ischemia for 15 min.+ reperfusion for 60 min.); 4) Total group (anesthesia + hemorrhagic shock for 20 min.+ volemic resuscitation+ hepatic ischemia for 15 min.+ reperfusion for 60 min.). The controlled hemorrhagic shock state was obtained by bleeding, on regular intervals, to equivalent volumes of 5% of the estimated blood volume until a mean arterial pressure of 40 mmHg was obtained, and maintained for 20 minutes. The volemic resuscitation done with lactated Ringer s solution and total blood (3: 1). The total hepatic ischemia was obtained by portal triad clamping during 15 minutes followed by reperfusion for 60 minutes. Samples of blood were collected in ali of the phases and the dosages of serum Jactatelevels and base excess were used to characterize the state of shock with low tissue perfusion. The animais were sacrificed by bleeding to death. Segments of the distal ileum and sigmoid colon were submitted to histologic studies for neutrophils counting. Statistical analysis was performedwith analysis of variance (ANOVA), test of Student-Newman-Keulsand Chi-square. A value of p <0.05 was considered to be significant. The results obtained show that the total hepatic ischemia for 15 minutes, followed by reperfusion for 60 minutes, did not prompt to a neutrophils influx to the gut on the animais of groups Pringle and Total. Also, it demonstrated that, the state of hemorrhagic shock, differently from the Pringle maneuver, was the main inductor factor of neutrophils accumulation on the distal ileum and sigmoid colon, for the group submitted, exclusively, to this type of aggression (Shock group), the counting showed higher values, and differed significantly from the other studied groups. During the experiment three animais died (9,3%), being two on the Shock group,and one on the Pringle group

ASSUNTO(S)

leucocitos

ACESSO AO ARTIGO

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