StatusThe thesis was presented on the 6 June, 2007
Approved by NCAA on the 20 September, 2007
Abstract– 0.70 Mb / in romanian
1.80 Mb /
The present study has been undertaken in order to establish the characteristic traits of the structural disorders in the vital organs (liver, heart, kidney, intestines) and of the accompanied changes of the blood biochemical indices (hepatic, cardiac and pancreatic enzymes) and renal clearance markers (creatinine, uric acid, urea) during a period of 90 min or 5 hours of hemorrhagic shock reproduced on 52 rabbits. Likewise, the effect of hyaluronic acid has been evaluated when this glycoaminoglycan was administered before the HS triggering or among of the shock resuscitation by infusion of the Ringer solution.
The obtained data indicate that the most pronounced damages of HS for a period of 90 min were developed in liver parenchyma, being occurred even histological signs of apoptosis and necrosis. The over common injuries fixed in all organs were represented by cell membrane alteration and cell edema, cytoplasm vacuolization, cell connecting disruption, interstitial and perivascular edema. The blood biochemical shifts showed the significant elevation of the enzymes level and of the renal functioning predictors. However these changes have been strongly blunted at 5th hour of shock demonstrating even a lowered values comparable with basal levels. This phenomenon apparently didn’t correlated with structural events which have progressed at late time of shock but has correlated with the fact of regional circulation exacerbation within prolonged survey of dynamics: progression of vascular spasm, blood extravasations and edema enhancement. Thus, the disconnecting of local circulation from central blood stream should be considered as an important opportunity of the advanced HS and of the biochemical dynamics emphasizing also its putative diagnostic significance.
The HS pretreatment with hyaluronic acid led to a lowered accent of structural injuries the most important feature being the absence of the hepatocyte apoptosis and necrosis amnd preserving of vascular tone. Nethertheless the enzymomia level was enhanced. In case of its administration during infuzional therapy hyaluronic acid has improved the evolution of the reperfusion syndrome leading to less expansion of the structural damages, to significant decrease of the liver enzymes, to normalization of the creatinine and urea levels.
Hence, this glycoaminglycane can be an additional support of the resuscitation efficacy based on its availability to fortify the antioxidant potency, to attenuate the inflammatory response and to optimize the endothelium dependent vascular reactivity. Being an important component of extracellular matrix hyaluronic acid reduces the risk of cell degradation, of the interstitial proteinases and of the apoptosis induced caspases activities improving likewise the phenomena linked with blood flow redressing such as reperfusion syndrome and non reflow repercussion.