Objective To construct a model of small caliber vascular endothelial growth factor(VEGF) in tissue engineering,to investigate the performance of the sustained-release microspheres and vascular stent,and to provide materials and theoretical basis for animal experiment.Methods The sheep carotid arteries were treated with a cellular reagents,the cellular conditions and the stent properties were observed.Preparation of sustained release microspheres containing VEGF,particle size,encapsulation efficiency,drug loading and release curve were measured.The effective combination of the slow release microsphere and the vascular stent was used in the freeze drying technology.The rat vascular endothelial cells grown in tissue engineered blood vessel model release lumen,observe the growth of endothelial cells.Results After the treatment,the original performance of the vascular stent can be maintained.The average particle size of the microspheres was (9.8 ± 6.0) μm,which could be released slowly in 20 days,and the release rate was 70％.Microspheres can effectively with the tissue.engineering blood vessel tight binding.Rat vascular endothelial cells can grow in the vascular stent surface.Conclusion Using Triton X-100,DNA/RNA ribozyme for acellular reagent,stent performance is good.PLGA microspheres have good sustained release performance,and constructing appropriate tissue engineered small caliber vascular release model by using freeze drying technology can make the stent compact structure.

【Objective】 To retrospectively analyze the blood transfusion of 322 patients with Stanford type A aortic coarctation in our hospital, and to explore the influencing factors of perioperative blood transfusion in patients and evaluate the effect. 【Methods】 The patients with Stanford A type aortic coarctation who underwent surgical treatment in our hospital from October 2020 to October 2023 were selected to analyze the differences in blood transfusion and the monitoring of blood routine and coagulation function between different surgical modalities, and to evaluate the influencing factors of massive blood transfusion. 【Results】 The intraoperative allogeneic red blood cell transfusion rate was 63.98% and the perioperative allogeneic red blood cell transfusion rate was 85.71% in patients with Stanford type A aortic coarctation. The intraoperative red blood cell, plasma, cryoprecipitates and platelet transfusion volumes for the Bentall procedure were (3.75±3.81) U, (608.13±314.77) mL, (15.25±8.39) U and (1.53±0.78) therapeutic doses, respectively, and had no difference compared with those for Sun′s procedure with the transfusion volume of (3.13±4.04) U, (707.61± 461.21) mL, (15.79±6.59) U and (1.54±0.64) therapeutic doses and those for Bentall&Sun’s procedure with the transfusion volume of (3.04±4.41) U, (813.48±582.02) mL, (18.39±6.43) U and (1.76±0.58) therapeutic doses(P>0.05). Preoperative hemoglobin levels were significantly lower in patients treated with Bentall procedure (127.75±23.17) g/L and in patients treated with Sun′s procedure (126.07±16.14) g/L than in patients treated with Bentall & Sun′s procedure(133.17±18.12) g/L(P<0.05). Postoperative hemoglobin, APTT and platelet counts were not statistically different between groups(P>0.05). Perioperative erythrocyte massive infusion accounted for 53.42%. The length of hospital days(days) in the massive transfusion group (23.83±9.74) was significantly higher than that in the conventional transfusion group (31.71±22.98), and the mortality rate in the massive infusion group 34.88% was significantly higher than that in the conventional transfusion group (5.33%)(P<0.05), and the hemoglobin level (g/L) at discharge in the massive infusion group(95.65±11.58)was lower than that in the conventional transfusion group(101.93±15.77)(P<0.05). 【Conclusion】 Blood transfusion is necessary to ensure the perioperative treatment of patients with acute Stanford type A aortic coarctation. Massive transfusion of red blood cells is accompanied by an increase in mortality rate and prolonged hospital stay. The test of coagulation function is helpful in guiding the use of blood components, and individualized restrictive transfusion strategy can reduce unnecessary blood transfusion and is conductive to patient safety.

【Objective】 To analyze the blood transfusion strategies in extracorporeal membrane oxygenation (ECMO) recievers in our hospital, so as to explore the clinical application and efficacy of blood transfusion in patients on ECMO. 【Methods】 Data from patients on ECMO treatment in our hospital from October 2017 to October 2021 was collected. The blood transfusion data and coagulation monitoring indexes during different ECMO modes were analyzed, and the efficacy of blood transfusion was evaluated. 【Results】 No difference in the number of blood transfusions was noticed by ECMO treatment modes.The transfusion units of red blood cells, plasma and platelets in VA mode were (28.35±14.60) U, (7 367.78±5 194.33) mL and (7.04±5.10) therapeutic volumes, which were higher than those in VV mode, i. e. (18.67±21.50) U, (4 836.67±6 640.50) mL and (3.60±7.47) therapeutic dose, respectively.In VA-ECMO mode, the Hb level and platelet count before ECMO treatment were (126.44±23.9) g/L and (223.84±67.62) × 10⁹/L, which were significantly higher than those after treatment (91.02±21.48) g/L and (172.86±127.73)×10⁹/L.In VV-ECMO mode, the APTT before ECMO treatment was (35.28±8.73) s, which was shorter than that after treatment (41.96±13.69) s. The levels of fibrinogen, Hb and platelet count were (3.80±1.85) g/L, (123.81±33.77) g/L and (175.72±98.91)×10⁹/L, which were significantly higher than the levels after treatment (2.78±1.08) g/L, (92.31±17.38) g/L and (125.31±98.14)×10⁹/L, respectively. 【Conclusion】 There are differences in the amount of blood transfusion among different modes of ECMO treatment. As blood transfusion is a necessary support to ensure ECMO treatment, the monitoring of coagulation index is conducive to reduce blood transfusion, improve the efficiency of blood transfusion and benefit to patient safety.

Objective: To retrospectively assess whether a lower hematocrit level (between 18% and 20%) had any impact on the safety of patients undergoing therapeutic plasma exchange (TPE), and to further determine the threshold for red blood cell supplementation prior to TPE. Methods: Clinical data from 181 adult patients who underwent TPE treatment at the Department of Blood Transfusion of our hospital from March 2023 to July 2024 were collected. The patients were divided into a study group of 44 patients (Hct ≥18% and <20%) and a control group of 137 patients (Hct≥20%). In two groups, blood volume-related safety indicators including respiration rate, heart rate, systolic blood pressure, and blood oxygen saturation levels before and after TPE were compared using t-test. Between-group differences in the grading of adverse reactions such as allergies and hypotension were analyzed using chi-square test. Results: A total of 659 TPE treatments were performed on 181 patients, with 169 TPE treatments on 44 patients in the study group (Hct≥18% and <20%) and 490 TPE treatments on 137 patients in the control group (Hct≥20%). There were no statistically significant differences in age, gender, BMI category, and the presence of cardiac insufficiency between the two groups. In the study group, there were no statistically significant differences in safety indicators such as respiration rate, heart rate, systolic blood pressure, and blood oxygen saturation level before and after TPE. In the control group, there were no statistically significant differences in heart rate and systolic blood pressure before and after TPE, but there were statistically significant differences in respiration rate and blood oxygen saturation level (P<0.05). There were no statistically significant differences in the grading of adverse reactions such as allergic reactions and hypotension between the two groups. Conclusion: For adult patients with stable conditions, maintaining a lower hematocrit level (Hct ≥18% and <20%) during TPE is relatively safe. It is feasible to lower the TPE red blood cell supplementation threshold to 18%≤Hct<20%，which may save blood resources while potentially benefit patients by avoiding unnecessary red blood cell transfusion.