CHANGE OF FUNCTIONAL AND LABORATORY PARAMETERS AFTER COMPENSATION OF ACUTE BLOOD LOSS WITH COOLED HYPERTONIC SOLUTION IN EXPERIMENT

Abstract

Relevance.High efficiency of hypertonic (hyperosmolar) solutions in acute blood loss is known. However, data on changes in the body, developing as a result of infusion of such drugs (including cooled) in the providing of care after acute blood loss is limited or absent. This fact complicates the development of tactics in their use, especially in emergency situations at low temperatures.Intention.To reveal features of functional and laboratory indicators In experiments on animals as a result of infusion of warm (+22 °С) or the cooled (–3 °С) hypertonic solution based on hydroxyethyl starch and sodium chloride (HyperHAES, further – HHES) at the acute blood loss of 50 % of blood volume (BV).Methodology.Animals (20 male sheep) with modeled blood loss were distributed into 2 experimental and 2 control groups of 5 animals each. Sheep in the 1st experimental group were placed in the heat chamber with temperature –7 °С for 15 min. Then they underwent the intravenous infusion of a cooled HHES at a dose of 4 ml/kg of weight through the jugular vein with a disposable syringe (volume 20 ml) evenly with a speed of 60 ml per minute. After that they were left in the heat chamber until the time of 1 hour in total. Individuals in the 2nd experimental group were injected with an equivalent volume of warm solution during the corresponding periods of the experiment at an external temperature of +22 °C. 1 hour after beginning of the infusion all animals were intravenously injected with colloidal solution based on hydroxyethyl starch (“Voluven”) at an external temperature of +22 °C. During 1 day the dynamics of rectal temperature, arterial pressure, heart rate and respiratory movements, osmolarity of blood plasma and content of osmotically active components, quantitative indicators of red blood were evaluated.Results.Animals at a temperature of +22 °C or at a temperature of –7 °C died in (82 ± 3) min and (70 ± 5) min (p < 0.05) respectively after the start of exfusion. Intravenous fluids (warm or cooled HHES) ensured the survival in 100 % of cases. As a result of blood loss, subsequent infusion of cooled HHES and following presence in the heat chamber, rectal temperature in sheep decreased by 4.9 °C (14.2%, p < 0.05) relative to the initial values. Two and 4 min after infusion of cooled or warm HHES systolic blood pressure increased by 24.9 % (p < 0.05) and 14.9 % (p < 0.05), respectively, and were restored to the normal level during the following 40 min. Infusion of “Voluven” contributed to the stabilization of blood pressure within 1 day after infusion of HHES. Blood loss led to increased heart rate by 2.1 times (p < 0.05), infusion of HHES slightly reduced the severity of tachycardia. Within 10 minutes after the introduction of cooled HHES, dynamics of heart rate was less stable. Infusion of warm or cooled HHES increased osmolarity of blood plasma by 9.5–9.9 % (p < 0.05), which was associated with an increase of sodium and glucose concentrations in blood. Infusion of “Voluven” reduced osmolarity of blood plasma, which became similar to initial values at the end of Day 1 after infusion of HHES. Blood loss, infusion of HHES and “Voluven” decreased quantitative indicators of red blood via removal of red blood cells from the bloodstream, as well as compensatory and post-transfusion hemodilution.Conclusion.The infusion of warm or cold hypertonic saline (HyperHAES) ensures the survival of experimental animals in post-hemorrhagic period. The positive effect of the drug is associated with compensatory haemodilution (including increased osmolarity of blood plasma), as well as with better functioning of the cardiovascular system. Specific cooled HHES effects include an earlier and pronounced rise in blood pressure. Considering changes in functional and laboratory parameters after infusion of warm or cooled HHES, a reliable system should be developed to remove casualties from emergency areas and to take earlier and complete diagnostic and treatment measures.