1.The estimation of traceability and uncertainty of measurement on the result of HBV DNA with different detecting system
Weifeng SHEN ; Jun FAN ; Pingyang SHAO ; Minjun HU ; Zhaofeng WANG ; Lixia ZHANG ; Renye DING ; Qingping YANG ; Yujun WANG
Chinese Journal of Laboratory Medicine 2011;34(3):271-275
Objective To study the uncertainty and traceability of HBV DNA assays and discuss the comparability of results among different detection systems. Methods Different detecting systems were used to detect HBV DNA using the national standard substance as "quality control substance". The uncertainty of the results was evaluated referring "Guidelines for estimating and reporting measurement uncerTAinty of chemical test results" of NATA The results were traced back to the national standard substance. According to the CLSI document EP9-A2, the results were analyzed and subjected to bias estimation with the t(0.05sv) √u2b1+ u2b2 as the criterion clinically accepted to investigate the comparability of different detecting systems. Results The means (-y) measured by 3 HBV DNA assay systems were 6.15,5.88,and 6.31 lg(kIU/L) respectively. Except system A,both the biases of system B and C had statistical significance (all P < 0. 05) and expanded uncertainty of three detection systems was varied, but the difference was within the maximum acceptable range (± 0. 5) of the external quality assessment by National Center for Clinical Laboratory. Being traceable to national standard substance, the results of HBV DNA of the three detecting systems were (5.45 ± 1.23), (5.55 ± 1.32) and (5.42 ± 1.25) lg(kIU/L), respectively.There was significant difference among three systems (F = 5.63, P < 0. 05). Comparing system A and B,there was significant difference in statistic (q = 5. 12, P < 0. 05) and the difference between system B and C also had statistically significant (q = 6. 85, P < 0. 05), but the results between system A and C had no statistical difference (q = 1.85,P > 0. 05). Among these three systems, the difference of any two detection systems had no statistical significance (all P > 0. 05). It showed that system bias was acceptable in clinical application and the results between different systems were comparable. Conclusions It is necessary to estimate the uncertainty and traceability when comparing the HBV DNA assay among the different labs. It also needs to estimate the bias of different systems and evaluate the clinical acceptability to ensure the accuracy and comparability of the results.
2.The study of erythrocyte fragility and morphological changes caused by roller pump in vitro.
Siwei XU ; Fang CHEN ; Minjun DING ; Rukun CHEN ; Suigen LU ; Hailin ZHONG
Journal of Biomedical Engineering 2002;19(3):419-422
To observe the erythrocyte fragility and morphological changes of erythrocytes caused by roller pump. Ten tests were divided into two groups, Polystan pediatric pump group A (n = 5) and COBE pump group B (n = 5). Ten whole blood samples (each 400 ml) were circulated in the roller pump for 16 h. Erythrocyte fragility and free hemoglobin were measured before pumping and at every 2 hours during pumping. The possible morphological changes of erythrocytes caused by roller pump were observed by scanning electron microscope. The electron microscopic observation was made before pumping and at every 4 hours throughout pumping. Results showed that the erythrocyte fragility of two groups was not increased during a long period of pumping. The number of acanthocytes of two groups was 1.77/1.81% in the samples before pumping and 6.12/7.13, 9.18/8.73, 13.21/12.89, 16.53/17.21% at 4 h, 8 h, 12 h, and 16 h respectively. The free hemoglobin level of two groups was increased linearly during a long duration of pumping and the index of hemolysis of two groups was 0.296 mg/L/h and 0.3993 mg/L/h respectively. The result shows: 1. the erythrocyte fragility was not increased during a long period of pumping; 2. the erythrocyte membrane was injured or broken by roller pump directly; 3. the morphological changes of erythrocytes would be the basis of post operative hemolysis.
Erythrocyte Deformability
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Heart-Lung Machine
;
adverse effects
;
Hemoglobins
;
analysis
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Hemolysis
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Humans
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In Vitro Techniques
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Osmotic Fragility
;
Time Factors
3.The significance of erythrocyte fragment count to predicting hemolysis in roller pumps.
Junqiang FAN ; Shiwei XU ; Fang CHEN ; Minjun DING
Journal of Biomedical Engineering 2008;25(3):632-636
Hemolysis in blood pumps has been measured by various in vitro tests, in which normalized index of hemolysis (NIH) was established. As NIH is complicated and difficult to calculate, erythrocyte fragment count (EFC) is proposed in the present study to predict hemolysis in roller pumps. Five paired in vitro tests were conducted using the POLYSTAN pediatric pump (group A) and COBE pump (group B). Ten whole blood samples (400ml) were circled in the roller pump for 16 hours. Erythrocyte fragments count and plasma-free hemoglobin (FHb) were measured before pumping and every 2 hours through circulation after 4 hours pumping. The morphological changes of erythrocyte were observed by scanning electron microscope. Simple linear regression analysis showed the two groups' EFC and FHb levels increased linearly during a long period of pumping, and the coefficient of determination (R2) was 0.64. These data suggested that Erythrocyte fragments count could be used as an index in evaluating the in vitro hemolytic properties of blood pumps.
Erythrocyte Deformability
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Erythrocytes
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ultrastructure
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Heart-Lung Machine
;
adverse effects
;
Hemoglobins
;
analysis
;
Hemolysis
;
physiology
;
Humans
;
Microscopy, Electron, Scanning
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Osmotic Fragility
;
Time Factors
4.Clinical study of anesthesia management and treatment strategies for emergency transcatheter aortic valve replacement
Wei HE ; Yi LIU ; Xianbao LIU ; Minjian KONG ; Xinping LIN ; Minjun DING ; Jifang CHENG ; Min YAN
Chinese Journal of Emergency Medicine 2022;31(7):944-947
Objective:To discuss the essentials of anesthesia management and treatment strategies for emergency transcatheter aortic valve replacement (TAVR), and to provide standardized recommendations for the development of emergency TAVR technology in China.Methods:This study retrospectively analyzed the relevant data of patients undergoing emergency TAVR surgery in the Second Affiliated Hospital of Zhejiang University School of Medicine from March 2019 to February 2021, including baseline patient characteristics, perioperative echocardiography data, prognosis and 30-day follow-up. Post-operative data were compared with pre-operative data using paired-sample test.Results:Thirteen patients, aged (75.62±9.63) years, underwent emergency TAVR surgery, and 6 of them were male. Eleven patients were New York Heart Association class Ⅳ. The preoperative Society of Thoracic Surgeons score was (20.31±15.15)%. The trans-aortic valve differential pressure was significantly reduced after surgery [(68.92±30.66)mmHg vs. (2.70±2.36)mmHg, P<0.01]. Two patients died within 30 days after surgery, one patient developed a new third degree atrioventricular block, one patient had a stroke, and 4 patients developed pulmonary infection. Conclusions:Emergency TAVR surgery is a feasible and effective rescue strategy for patients with aortic stenosis in critical condition. The establishment of anesthesia standard operation procedure process for TAVR surgery helps ensure homogenized medical behavior and good teamwork.