A Comparative Study On Changes In Morphology,Structure And Function Of Erythrocytes After Intraoperative Blood Salvage Between Diabetic And Non-diabetic Patients

Objective:To systematically evaluate the safety and effectiveness of intraoperative blood salvage for diabetic patients by observing the morphological structure and function of washing autotransfusion red blood cells in diabetic and non-diabetic patients as well as the changes of red blood cell related indicators before and after autologous blood transfusion.Methods:Approved by the Medical Ethics Committee of Gongli Hospital Affiliated to Naval Military Medical University,and signed an informed consent form with the patient or authorized client.60 patients who underwent elective orthopedic surgery in our hospital from September 2019 to December 2020 were selected,aged 50 to 64 years,regardless of gender,BMI:19-28 kg/m²,ASA classification I and II.The types of surgery include hip replacement,posterior lumbar decompression and interbody fusion,open reduction and internal fixation of femoral fractures.According to the history of diabetes,60 patients were divided into the following two groups,group A:patients with type 2diabetes surgery,Hb A1c≥7%,group B:patients without diabetes surgery.Exclusion criteria:anemia,malignant tumors,spinal tuberculosis,hematological diseases,contaminated blood in the surgical field,blood loss less than 300ml during the operation,transfusion of foreign blood during the perioperative period,etc.（1）Collect central venous blood,and detect RBC count,Hb,Hct,MCV,MCH,MCHC,RDW before surgery（T₁）,after autologous blood collection（T₃）,and after surgery（T₄）.（2）Collect arterial blood before autologous blood collection（T₂）,collect autologous blood in the blood bag after autologous blood collection（T₃）to compare the changes of blood gas analysis（p H,Na⁺,K⁺）,red blood cell deformability（red blood cell morphology score under oil microscope,ELISA method to detect Na⁺-K⁺-ATPase）,red blood cell oxygen release capacity(calculate P₅₀ value,ELISA method to detect 2,3-DPG)and red blood cell apoptosis rate（use flow cytometry to detect the PS positive rate of red blood cell）before and after blood salvage.Results:Compared with before surgery,the RBC counts,Hb and Hct of the two groups of patients after autologous blood collection and after surgery were significantly decreased（P<0.05）;compared with after autologous blood collection,the RBC counts,Hb,Hct after surgery were significantly increased（P<0.05）;there were no significant differences in the red blood cell related indicators before surgery,after autologous blood collection,and after surgery between two groups（P>0.05）.Compared with the blood before autologous blood collection,the p H value and Na⁺content of the autologous blood of two groups of patients were significantly increased,the K⁺content was significantly decreased（P<0.05）;there was no significant differences in the red blood cell deformability（red blood cell morphology score,Na⁺-K⁺-ATPase activity）（P>0.05）;the red blood cell oxygen release capacity(P₅₀ value,2,3-DPG content)and the red blood cell apoptosis rate（PS positive rate）of two groups were significantly increased after autologous blood collection（P<0.05）.Compared with non-diabetic patients,there was no significant difference in p H,Na⁺content,K⁺content,Na⁺-K⁺-ATPase activity and P₅₀value before autologous blood collection and after autologous blood collection in diabetic patients（P>0.05）;Observed under the oil microscope,the red blood cells in the state of the disc with spinous process and the state of spinous process were significantly increased,and the red blood cells in the spherical state were occasionally seen.The 2,3-DPG content and the positive rate of PS were significantly increased（P<0.05）.Conclusion:Intraoperative blood salvage has a certain positive effect in elective orthopedic surgery,and intraoperative blood salvage for diabetic patients can effectively save blood resources.Compared with non-diabetic patients,diabetic patients’red blood cell double-concave disc-shaped morphology changes,the oxygen release capacity is still within the normal range and PS valgus is increased.The deformability of autologous red blood cells in diabetic and non-diabetic patients is not affected after intraoperative blood salvage,and the ability to release oxygen increases,but the increase in PS valgus of red blood cells increases the phagocytosis of autologous red blood cells in the body by mononuclear macrophages after reinfusion risk.