The role of mandible injury in the pathogenesis of biochemical and functional liver disorders caused by acute blood loss and two-hour ischemia of limbs, and the efficiency of their correction by carbacetam

Abstract

Introduction. In the modern world, the prevalence of gunshot wounds has increased significantly. The main cause of death under conditions of gunshot wounds is acute massive blood loss from the extremities. Applying hemostatic tourniquet according to these conditions belongs to the basic aid measures for the wounded on the battlefield. In the structure of gunshot wounds, despite the injury of the extremities, has recently significantly increased the frequency of frontal part injuries of the skull, which remains the least protected part of the body of combatants. There are lesions of the face and facial skeleton in a third of cases with such injuries. However, the effect of mandibular fracture on systemic disorders of acute blood loss complicated by two-hour ischemia-reperfusion of the limb, practically not studied, there are no data on the effectiveness of carbacetam in the case of these conditions.Objective of research: to determine the role of mandibular injury in the pathogenesis of metabolic and functional disorders of the liver caused by acute blood loss and two-hour ischemia of the limb, and to establish the effectiveness of their correction with carbacetam.Materials of the research and their discussion. The experiments were performed on 106 nonlinear male rats weighing 200-220 g. All animals were divided into four groups: control and three experimental. In the first experimental group, the animals were modeled acute blood loss (20% of the circulating blood volume) by intersection of the femoral vein. Ischemia-reperfusion of the limb was simulated on the adjacent thigh by applying a strip of elastic tourniquet "SWAT-T" (USA)10 mm wide for 120 minutes proximately on the left foot. In the second experimental group, animals with acute blood loss and ischemia-reperfusion of the limb, a fracture of mandible from the left was additionally simulated. In the third experimental group, animals with acute blood loss, ischemia-reperfusion of the limb and mandibular fracture for corrective purposes were intraperitoneally administered carbacetam at a dose of 5 mg per kilogram of animal weight.After 1 and 2 hours, as well as after 1, 7 and 14 days in experimental animals were determined indicators of bile-forming, biliary and absorption-excretory function of the liver. Liver homogenate was used to determine the content of thiobarbituric acid reagents (TBA-active LP products), catalase activity, antioxidant-prooxidant index (API) was calculated, and alanine aminotransferase (ALT) activity was determined in serum.Result of the research and their discussion. It is established that modeling of acute blood loss complicated by ischemia-reperfusion of the limb is accompanied by increased intensity of lipid peroxidation processes in the liver, depletion of antioxidant protection with a shift of antioxidant-prooxidant balance towards the strengthening of prooxidant mechanisms. This leads to increased cytolysis and the formation of liver disorder, which is manifested by a slowdown in the formation of total bile acids and the rate of bile secretion with a maximum after 1 day of observation.In the case of these conditions, additional fracture of the mandible contributes to the deterioration of the biochemical and functional state of the liver with a maximum of 1-7 days of observation. By 14 days, the indicators improve, but do not reach the level of control.Thus, a fracture of the mandible exacerbates the severity of systemic disorders caused by acute blood loss and ischemia-reperfusion of the limb. The use of carbacetam under these conditions caused a significant decrease in the content of TBA-active products in the liver, an increase in catalase activity and the value of API after 7-14 days of use. There is also a decrease in the activity of ALT in the blood serum, an increase in the content of total bile acids in the bile, the rate of bile excretion and a decrease in the duration of excretion of bromosulfalein.Conclusions: Additional simulation of mandibular fracture on the background of acute blood loss and ischemia-reperfusion of the limb is accompanied by a deepening of metabolic and functional disorders in the liver. The use of carbacetam for 7-14 days in the reperfusion period for animals with acute blood loss, ischemia-reperfusion of the limb and mandibular fracture, compared with animals without correction, causes a significant decrease in the intensity of lipid peroxidation and cytolysis, less depletion of bile-forming, biliary and absorption -excretory function of the liver.

Keywords

• mandibular fracture
• blood loss
• tourniquet
• ischemia
• reperfusion
• liver function