血糖测定前误差的影响因素及解决方法探讨

Analysis of Pre Analytic Errors Caused by Continuing Glycolysis in Vitro in Glucose Determinations

目的：探讨糖酵解引起的离体血糖下降所造成的血糖分析前误差的主要影响因素及解决方法。方法：随机抽取30例志愿者血标本，观察在4℃、25℃、37℃条件下血糖随时间（0h、2h、4h、6h、8h）下降速度；调查40例门诊患者因分析前误差造成的血糖测定偏差；分析普通玻璃管及各种真空采血管（加糖酵解抑制剂、促凝剂、促凝剂＋分离胶）及血标本处理方式在减少离体血糖下降的作用。结果：4℃放置8h未离心标本，血糖平均下降1．01mmol／L；而在37℃，血糖平均下降5．07mmol／L。40例门诊患者由分析前误差造成的血糖测定平均降低（0．652±0．351）mmol／L，容易造成糖尿病的误漏诊；氟化钠在前1～2h抑制效果差；甘油醛抑制剂能保持血糖8h基本不下降；30例促凝剂管采血后尽早离心（15min），离心后放置4h平均血糖下降（0．113±0．031）mmol／L。结论：离体血糖的下降速度与血标本采集处理方式、温度、放置时间、管洁度密切相关；采用加促凝剂的真空管采血且及早离心、加甘油醛为血糖抑制剂的方法能较好地解决离体血糖下降引起的分析前误差问题。

Objective：To analyze the main effect to prenanlytic errors caused by continuing glycolysis in glucose determinations and the approaches to minimize glucose loss, Methods：The glucose concentration in heparinized blood from 30 volunteers was determined at 4℃ ,25 ℃and 37 ℃when immediate 0 h,2 h,4 h,6 h and 8 h. The prenanlytie errors from outpatients received OGTT and FPG test were estimated, The common glassy tube and various vacuum tubes with antiglyeolytic agent （glyceraldehydes）, or with clot activator,or with clot activator and gel separator and blood collection approaches were evaluated to minimize glucose loss. Results;At 4 ℃ glucose concentrations d.ecreased 1. 01 mmol/L in 30 volunteers uneentrifuged blood after 8h on average and at 37℃it decreased 5.07 mmol/L. The prenanlytic error caused by continuing glycolysis in glucose determinations was （0. 652±0. 351） mmol/L in outpatients received OGTT and FPG test. Glyeeraldehydes preserved glucose concentration for up to 8 h at 30℃ but fluoride had not effective until after 1 - 2 h. Conclusiori： Glucose concentrations decrease in blood specimens during transport/processing closely relates with blood sample collected ways and prolonged time and ambient temperature and contamination. The use of two ways that serum collected in glass tubes with clot activator and timely centrifugation and collected in glass tubes with glyeeraldehydes as antiglycolytic agents can contribute to reduce the pre-analytical errors caused by continuing glycolysis in vitro in glucose determinations.