全血黏度测定质控品的适用性研究

目的 分析比较1种非牛顿流体质控品对3种血液黏度计的适用性,探讨全血黏度测定质控品的适用性对室内质控及实验室间比对活动的影响.方法 用血液黏度计B、C、D在3种不同切变率下(1 s~(-1)、30 s~(-1)、200 s~(-1))对30份全血标本进行平行测定,根据测定结果绘出3台血液黏度计的全血切变率-黏度曲线.同时,在1个工作日内用上述3种血液黏度计对质控品A进行10次平行测定,根据测定结果绘出3台血液黏度计的质控品A切变率-黏度曲线.然后,在4个工作日内再用3种血液黏度计每日分别测定原厂家配套质控品及质控品A各5次,对每台血液黏度计的原厂家质控品及质控品A的4组日测定值进行F检验,考察其日测定值间是否有差异.最后,将质控品A分发给全国49家实验室,各实验室对其进行全血黏度测定,测定结果按实验室所用血液黏度计不同分为血液黏度计B组(20家)、血液黏度计C组(20家)与血液黏度计D组(9家),计算各组在切变率为1 s-1下的组内变异系数.结果血液黏度计B、C、D对30份全血标本的测定结果有较大差异,切变率1 s-1下的测定结果依次下降(23.88±1.63)、(20.40±1.97)、(13.52±1.43)mPa·s];切变率200 s-1下却依次升高(3.39±0.36)、(4.88±0.51)、(5.34±0.66)mPa·s];切变率30 s-1下血液黏度计C测值最高,余者依次为仪器D与B分别为(8.14±0.75)、(6.97±0.83)、(4.74±0.68)mPa·s].3台血液黏度计对质控品A进行测定时,切变率1 s-1下的测定结果依次降低(22.29±0.56)、(16.93±0.71)、(6.01±0.10)mPa·s];切变率30 s-1下血液黏度计C的测值最高,其次为B与D分别为(7.35±0.07)、(4.29±0.05)、(3.57±0.05)mPa·s];切变率200 s-1时的测定结果依C、D、B的顺序下降(3.43±0.03)、(3.07±0.04)、(2.92±0.04)mPa·s].分别比较3台血液黏度计测定原厂家质控品及质控品A的4组日测定值,切变率1 s-1下血液黏度计B测定原厂家质控品与质控品A的日测定值问差异无统计学意义(F值分别为2.63和1.37,P均>0.05),血液黏度计C与D测定原厂家质控品的日测定值间的差异也无统计学意义(F值分别为0.33和3.14,P均>0.05),但测定质控品A的日测定值间差异有统计学意义(F值分别为5.76和8.00,P均<0.05);切变率30s-1下3台血液黏度计测定原厂家质控品的日测定值间差异无统计学意义(F值分别为0.31、0.18和2.26,P均>0.05),对质控品A的日测定值间也差异无统计学意义(F值分别为1.03、1.83和2.40,P均>0.05);切变率200 s-1下3台血液黏度计测定原厂家质控品的日测定值间无差异(F值分别为2.59、0.68和2.96,P均>0.05),对质控品A的日测定值间亦差异无统计学意义(F值分别为2.31、3.01和2.28,P均>0.05).全国49家实验室在切变率1 s~(-1)下测定质控品A,血液黏度计B、C、D组的测定结果分别为(18.47±1.30)、(11.17±2.38)、(8.17±5.21)mPa·s,其中血液黏度计B组的组内变异最小(7.03%),血液黏度计D组与C组的组内变异依次为63.75%,21.31%.结论 质控品A可以在血液黏度计B上稳定模拟全血流变特性,但在血液黏度计C与D上只能部分模拟全血,故质控品A最适用于仪器B.由于人工制备的非牛顿流体质控物只能在一定条件下模拟全血的流变特性,因此实验室在选择室内质控品时应注意评价其流变学特性与全血的相似程度,只有在测定时可以近似模拟全血的候选品才可作为全血黏度测定的质控品.在选择第三方质控品作为实验室间比对用标本时,同样也需重视其适用性问题.通过充分的预实验以明确所选用质控品的适用性,可最大程度地减少由标本适用性所带来的室间差异,使实验室间比对结果能准确反映实验室检测质量.

Research of applicability of control samples in measurement of whole blood viscosity

Objective To exlore the influence of internal quality control and external quality control assessment(EQA) resulting from applicability of control samples in measurement of whole blood viscosity (WBV) through the analysis and comparison of applicability of 1 non-Newtonian fluid internal quality control sample in 3 viscometers. Methods Viscometer B, C and D were used to measure WBV of 30 blood samples in parallel under the shear rate(SR) of 1 s-1,30 s~(-1) and 200 s~(-1), then the blood SR-WBV curves of 3 viscometers were drawn according to the results. At the same time, viscometers B, C and D were used respectively to determine the WBV of control A 10 times in one day, then the control A SR-WBV curves were mapped. Three viscometers were used to measure the manufactory control samples and control A 5 times in one day for 4 days. Four groups of daily values of manufactory control samples and control A of each instrument were used to carry out F test to calculate whether 4 daily values are difference. Finally, the control A was dispensed in 49 laboratories nationwide chosen for measurement. On the basis of viscometer used, 20 laboratories were classified as group B, 20 laboratories were classified as group C and 9 laboratories were classified as group D. Then the data under SR of 1 s~(-1) were analyzed to calculate the coefficient of variation (CV) in the group. Results There was significant difference among the WBV of blood samples measured by the viscometers B, C and D. The results under SR of 1 s~(-1) declined in turn, and they were highest under SR of 30 s~(-1) followed by the values of viscometer D and B and they were (8.14±0.75), highest under SR of 30 s-1 followed by the values of viscometer B and D, and they were (7.35±0.07), daily values of manufactory control and control A of each instruments in four groups were compared. Under SR of 1 s~(-1), there was no difference between daily values of manufactory control and control A in viscometer B (F = 2.63, 1.37, P > 0.05), and there was no difference of daily values of manufactory control among viscometer C and D (F = 0.33,3. 14, P > 0.05), but significant daily difference existed when control A was tested by viscometer C and D (F = 5.76, 8.00, P < 0.05). Under SR of 30 s~(-1), there was no difference of daily values of manufactory control among 3 viscometers(F =0.31, 0.18, 2.26, P >0.05), and there was no difference of daily values of control A among 3 viscometers' (F = 1.03, 1.83, 2.40, P > 0.05); Under SR of 200 s~(-1), there was no difference of daily values of manufactory control among 3 viscometers (F =2.59, 0.68, 2.96, P > 0.05), and there was no difference of daily values of control A among 3 viscometers (F=2.31, 3.01, 2.28, P>0.05). When control A was tested under SR of 1 s~(-1) in 49 laboratories nationwide, the WBV values in groups of viscometer B, C and D were (18.47±1.30), (11.17±2.38), viscometer D and C were 63.75% and 21.3%. Conclusions Control A could fully mimic the properties of whole blood steadily on viscometer B, but partially mimic viscometer C and D, so the control A is most appropriate for viscometer B. Because current non-Newtonian fluid internal quality control could mimic rheological properties of whole blood under specifically conditions, laboratories should evaluate the consistent degree between control and whole blood, only the candidates which can mimic the properties of whole blood approximately could be chosen as quality control of WBV. When third-party control is chosen to be samples of EQA, its applicability should be in consideration. Pretest should be performed adequately to define applicability of third-party control, so as to reduce the difference among laboratories due to applicability of control and reflect detection quality of laboratories exactly.