Comparison of syndecan-1 levels in terms of glycocalyx shedding levels after different fluid treatments following induced hemorrhagic shock in rats

Acute hemorrhage can be defined as rapid blood loss that accompanies various medical or surgical events. Hemorrhagic shock occurs when there is a significant loss of blood to the extent that it jeopardizes normal physiological compensatory responses, tissue perfusion, and oxygenation. This is a circulatory system failure requiring urgent resuscitation due to inadequate organ perfusion leading to systemic inflammation, organ dysfunction and ultimately death. In treatment, the two primary goals are to achieve hemorrhage control and promptly replace the lost blood with appropriate fluids. In addition to shock-related morbidity, resuscitation fluids can lead to cardiac and pulmonary complications, a systemic inflammatory response, edema, coagulation and electrolyte/acid-base abnormalities. Vascular walls have an adhesive layer on their inner surface known as the endothelial glycocalyx (EG), which is composed of proteoglycans (such as syndecan-1) and glycosaminoglycans (including heparan sulfate, chondroitin sulfate, and hyaluronan). The EG barrier can be a significant determinant in vascular homeostasis. Endothelial cell dysfunction plays a significant role in the microcirculation, including leukocyte adhesion to endothelium, red blood cell (RBC) disorders, and changes in vascular smooth muscle cells. The inadequacy of inflammatory activation due to endothelial dysfunction can enhance and prolong the inflammatory process. Therefore, the impairment of its components has been associated with endothelial damage, tissue dysfunction, and mortality in trauma patients. In this study, a rodent hemorrhagic shock model was established, and commonly used resuscitation fluids were administered. To assess the effects on the endothelial glycocalyx (EG) in vivo after resuscitation, syndecan-1 levels were measured in the blood at 0 minutes, 30 minutes, 60 minutes, and 120 minutes. In this experimental rat study utilizing a hemorrhagic shock model, our aim was to compare three different intravenous resuscitation fluids with groups receiving no intravenous resuscitation fluid, focusing on EG damage. When evaluated over time, a continuous increase was observed for each of the four groups, with the increase showing statistical significance between time intervals (p=0.001<0.05). However, when comparing the data obtained based on groups, no statistically significant difference was found (p=0.671 >0.05). Upon evaluation of these results, the limitation of our study lies in the fact that the number of animals in the groups was analyzed with less power than the minimum number of subjects required by ethical principles of animal experimentation. Increasing the number of subjects may lead to a closer approach to the statistical significance value. Although there was no statistically significant difference in terms of EG damage between colloid, crystalloid, and albumin fluids administered in hemorrhagic shock, the untreated control group exhibited a significantly slower increase than the other groups. All fluids caused varying levels of EG damage.