Application of recovery autotransfusion
The efficiency of recovering red blood cells in the current recovery type autologous blood transfusion is moderate, about 57% of the blood is recovered, and the range of change is about 20%. Some scholars have proposed the use of recovery autotransfusion technology to reduce the proportion of patients receiving allogeneic blood transfusion by 38%[6–7]. In patients undergoing major orthopedic elective surgery, intraoperative use of recovery autotransfusion will increase hospitalization costs, but it significantly reduces the need for intraoperative and postoperative allogeneic blood transfusion, and increases hemoglobin and hematocrit on the first day after surgery level. Considering the adverse effects such as complications and long-term hospitalization caused by the use of allogeneic blood transfusion, the cost increase caused by the use of recovery autotransfusion may be neglected[8–9]. The results of this study show that both diabetic and non-diabetic patients have a considerable degree of blood loss before the autologous blood is recovered. After the autologous blood is retransfused before the operation, the red blood cell related indicators have risen, and there is no postoperative anemia, and the foreign body must be retransfused. The condition of blood indicates that the application of recovery autotransfusion in elective orthopedic surgery has a certain positive effect. Diabetic patients undergoing recovery autotransfusion effectively saves precious blood resources.
Changes of red blood cell deformability in recovered autotransfusion
The gradual changes of red blood cell membrane damage are divided into three morphological stages. The first stage is a smooth double concave disc called disc cell (D); the second stage of red blood cell appears more and more bulge, called The spinous cell (E), the cell becomes more and more spherical; the erythrocyte bulge of the third stage disappears completely and is called the spheroid cell (S). When the percentage of S in the red blood cell unit is low, it tends to show low hemolysis and high ATP level. Some studies have calculated that the Pearson coefficient of hemolysis and S percentage is R = 0.85, and there is an approximately linear relationship between the two, showing that the S percentage is useful for assessing red blood cell damage Meaningful. The results of this study showed that the red blood cells collected from the autologous blood of the two groups occasionally saw spinous process and spherical state, and the morphological score increased slightly, but there was no statistical difference compared with the red blood cell morphological score before the autologous blood collection. Compared with non-diabetic patients, the red blood cell discs with spinous processes and spinous processes in diabetic patients before and after the recovery of autologous blood have significantly increased red blood cells, occasionally spherical red blood cells, and the red blood cell morphology score is significantly increased, indicating The morphology of red blood cells in diabetic patients is damaged to a certain extent, and the deformability of red blood cells is reduced. However, the recovery of autotransfusion has no obvious adverse effect on the deformability of red blood cells, and the recovery of red blood cells after transfusion does not increase the risk of hemolysis.
Na+-K+-ATPase is an enzyme that exists on the surface of all eukaryotic cells. Its activity also provides power for the secondary active transport of solutes such as amino acids, phosphates, vitamins, and glucose in epithelial cells. The decrease of Na+-K+-ATPase activity caused by diabetes causes Na + ions to accumulate in cells, and then free Ca2 + ions are accumulated due to the competition of transmembrane exchange, which leads to the decrease of red blood cell deformability, which reduces microvessels by coordinating with affecting the regulation of microvessels. Blood flow, which in turn increases blood viscosity. The results of this study showed that there was no statistical difference in the red blood cell Na+-K+-ATPase activity between the two groups of patients before and after the autologous blood collection, and there was no difference in the red blood cell Na+-K+-ATPase activity between diabetic patients and non-diabetic patients. The statistical difference indicates that the red blood cell Na+-K+-ATPase activity of patients with type 2 diabetes has not been severely damaged, which is consistent with previous studies, and the recovery of autologous blood transfusion does not reduce the red blood cell Na+-K+-ATPase activity. Combined with the results of the previous red blood cell morphology analysis, the red blood cell deformability of diabetic patients is slightly reduced, and the recovery of autologous blood transfusion will not aggravate the damage of the red blood cell membrane of diabetic patients, and the safety of autologous blood transfusion can be guaranteed.
Changes in oxygen release ability of recovered autotransfusion red blood cells
Normally, normal patients can easily overcome undesirable changes such as decreased ability to unload oxygen to tissues and increased venous oxygen tension by increasing the blood flow in the microvasculature. However, in diabetic patients with microvascular disease, such compensatory microvascular changes are impossible. The concentration of HbA1c in red blood cells of diabetic patients is higher, and its oxygen affinity is about ten times higher than that of non-glycosylated hemoglobin. However, the oxygen affinity in the blood of diabetic patients is not significantly different from that in healthy subjects. Some researchers have speculated that reducing the oxygen affinity of hemoglobin by stabilizing deoxygenated hemoglobin and increasing the 2,3-DPG in diabetic patients compensates for the effect of HbA1c. However, comparing the oxygen release kinetics of hemoglobin in diabetic patients and healthy subjects, and After determining the influence of 2, 3-DPG, the hemoglobin oxygen dissociation rate constants of the two groups did not differ. The increase in 2, 3-DPG is not the main factor that compensates for the influence of HbA1c on the oxygen release of diabetic patients, but is for the patients with blood vessels. The result of red blood cell compensation for tissue hypoxia in diabetic patients with the disease[13–14]. The results of this study showed that compared with before autologous blood collection, the red blood cell P50 value and 2, 3-DPG content of the two groups of patients after autologous blood collection increased significantly, and between diabetic and non-diabetic patients before autologous blood collection, autologous blood collection There was no statistical difference in the P50 value of red blood cells, but the content of 2,3-DPG was significantly increased. It shows that the oxygen release ability of red blood cells in diabetic patients has not been significantly damaged. The diabetic patients selected in this experiment have higher HbA1c, and their red blood cell 2, 3-DPG content compensatively increases, indicating that there may be a certain degree of vascular disease in the body. The blood processing in the process of autotransfusion washes away the red blood cells with weak viability and severe damage, so that the recovered autologous blood has an enhanced ability to release oxygen.
Changes of red blood cell apoptosis and injury in recovered autotransfusion
Red blood cells rarely undergo direct mechanical destruction in blood vessels, and 90% of red blood cells undergo apoptosis through phagocytosis by the mononuclear macrophage system. The increase in vascular osmotic pressure caused by hyperglycemia in diabetic patients and the osmotic diuresis triggered by glucose can accelerate the formation of hypertonic environment in the body, which, together with the high oxidative stress level in diabetic patients, promotes the decline of red blood cells. The PS exposure of red blood cells in type 2 diabetic patients increased significantly, and the count of reticulocytes also increased accordingly. The occurrence of anemia was caused by accelerated red blood cell loss rather than impaired red blood cell production. The reduction in the survival rate of red blood cells in diabetic patients promoted the increase in red blood cell turnover. High, to compensate for the normal operation of the body. The results of this study showed that the PS-positive rate of red blood cells after autologous blood recovery in the two groups increased significantly compared with before autologous blood collection. Compared with non-diabetic patients, the PS-positive red blood cells of diabetic patients before autologous blood recovery and autologous blood recovery were positive. Significant increase, indicating that diabetic patients' red blood cell membrane PS has an increased rate of ectropion, which is easy to adhere to the blood vessel wall and cause circulatory blockage, and is recognized by mononuclear macrophages. The recovery of autologous blood transfusion has aggravated the PS outside of the red blood cell membrane in diabetic and non-diabetic patients. Turnover rate increases the possibility of autologous red blood cells being phagocytosed by mononuclear macrophages after reinfusion, indicating the risk of reduced effectiveness of retrieving autologous blood transfusion.