Morphofunctional reconstruction of venous bed in ileum at postresection portal hypertension and its correction

Abstract

The aim of the work: to investigate the features of the morphofunctional reconstruction of the venous bed of  ileum  at postresection portal hypertension and its correction.

Materials and Methods. The research was conducted on 60 male rats, which were divided into 4 groups. The group 1 consisted of 15 intact animals, group 2 – 15 rats after resection of the right and left side parts of the liver (58.1 %), group 3 – 15 animals after removal of 58.1 % of liver parenchyma and splenectomy, group 4 – 15 rats after resection of 58.1 % of the volume of the liver and omentopexy. Euthanasia of animals was carried out by bloodletting in conditions of thiopental anesthesia 1 month from the beginning of the experiment. Histological medicine was made from the ileum.  The diameters of the postcapillary venules, venules, veins, the height of the endothelial cells, their nuclei, the nuclear-cytoplasmic relations in the endothelial cells, and the relative volumes of the damaged endotheliocytes were measured. Quantitative indicators were processed statistically.

Results and Discussion. Postresection portal hypertension was detected one month after resection of 58.1 % of the liver volume. The diameter of the postcapillary  venules  statistically significantly increased by 38.9 %,  resection of the liver and splenectomy the morphometric parameter decreased by 15.4 % compared with the previous indicator,  removal of 58.1 % of liver parenchyma and omentopexy – by 18.3 % . The given morphometric parameters at corrective operations did not reach the control and differed respectively from 17.4 and 13.5 % respectively. The diameter of the venules hemomycrocirculatory bed of the ileum in conditions of postresection portal hypertension increased by 34.2 %, and after splenectomy and omentopexy, respectively was reduced by 11.3 % and 13.0 %. At postresection portal hypertension, the diameter vein of ileum increased by 15.0 %, and after splenectomy and omentopexy decreased by 4.7 % and 7.4 % respectively. The height of the endothelial cells of the venous vessels of  ileum  in postresection portal hypertension decreased by 9.9 % compared with control, and in the conditions of postresection portal hypertension corrected a splenectomy – by 4.5 %, and with resection of 58.1 % of liver  and omentopexy – by 3.4 %. The nuclear-cytoplasmic relations in the endothelial cells at postresection portal hypertension  increased by 5.2 %, resection of 58.1 % of liver parenchyma and splenectomy – by 3.4 %, removal of liver  and omentopexy – by 3.1 %. The relative volume of damaged endothelial cells in the studied conditions of the experiment respectively increased by 23.1, 18.3 and 16.9 times compared to control. Optically the walls of the veins are fuzzy with the alternation of swollen and sclerotic foci, hypertrophied and thin areas. Violation of venous outflow, deposition of blood in the veins leads to hypoxia, dystrophy, necrobiosis of epithelial cells, smooth myocytes, stromal structures of organ. Damage  a significant number of endothelial cells was complicated by endothelial dysfunction and increased hypoxia. Unevenness of the lumen, deformation of the walls of the veins, their narrowing and hyalinization, extension of the sites indicated a violation of the venous drainage system of the ileum. Resection of large volumes of liver parenchyma leads to postresection portal hypertension and marked remodeling of the venous bed of ileum which is characterized by considerable expansion and plethora of venous vessels, a violation of their venous drainage function, hypoxia, dystrophic, necrobiotic, infiltrative and sclerotic processes in the organ under study. The combination of removing large volumes of liver and corrective surgery significantly improves the morphofunctional state of the veins of ileum.