Grieme Caleb V, Voss Dena R, Davis Scott R, Krasowski Matthew D
Clin Lab. 2017 Mar 1;63(3):561-568. doi: 10.7754/Clin.Lab.2016.160932.
The prevalence of hemolysis, icterus, and lipemia (HIL) was determined for residual whole blood specimens analyzed for clinical chemistry parameters on blood gas analyzers. The frequency and potential impact of exogenous interference from iodide, salicylate, and thiocyanate (metabolite of sodium nitroprusside) on analysis of whole blood chloride was also assessed.
Over an approximately two month period at an academic medical center, indices for HIL were determined on Roche cobas c502 analyzers for 1,986 residual whole blood specimens that had been previously analyzed for clinical chemistry parameters on Radiometer ABL90 FLEX blood gas analyzers. To examine exogenous interferences, retrospective analysis was performed over multiple years to ascertain whether patient samples analyzed for whole blood chloride were potentially affected by interference from iodide, salicylate, or thiocyanate.
Some degree of hemolysis (defined as hemolysis index of greater than 60) was present in 9.7% of the whole blood specimens. Increasing rates of hemolysis were associated with higher whole blood potassium concentrations. Nearly 60% of specimens with potassium concentrations between 6.0 and 6.9 mEq/L had hemolysis indices of 100 or greater, and 75% of specimens with a potassium concentration of 7.0 mEq/L or greater were severely hemolyzed (hemolysis index of 300 or greater). In contrast to the hemolysis results, icterus and lipemia were determined to have minimal impact on patient results. For the exogenous interferences, we did not identify any patient samples where elevated salicylate levels or pharmaceutical iodide administration overlapped with whole blood chloride analysis (out of 75,887 and 169,229 total chloride measurements, respectively). We did, however, find that for patients receiving nitroprusside therapy in the inpatient setting, whole blood chloride concentrations were significantly higher during nitroprusside therapy [106.7 +/- 6.2 mEq/L (mean, SD)] compared to before or after nitroprusside therapy (103.1 +/- 7.7 mEq/L).
In this analysis of whole blood specimens, hemolysis is a common interference and likely to introduce meaningful biases, as illustrated with potassium analysis. Icterus, lipemia, salicylate, and iodide appear unlikely to cause clinically significant bias. Nitroprusside therapy introduced a slight rise in whole blood chloride concentrations that probably has minimal clinical significance.
对在血气分析仪上分析临床化学参数的剩余全血标本，测定溶血、黄疸和脂血（HIL）的发生率。还评估了碘化物、水杨酸盐和硫氰酸盐（硝普钠的代谢产物）对外源性干扰全血氯化物分析的频率和潜在影响。
在一所学术医疗中心约两个月的时间里，在罗氏cobas c502分析仪上对1986份先前在雷度ABL90 FLEX血气分析仪上分析过临床化学参数的剩余全血标本测定HIL指标。为检查外源性干扰，进行了多年的回顾性分析，以确定分析全血氯化物的患者样本是否可能受到碘化物、水杨酸盐或硫氰酸盐干扰的影响。
9.7%的全血标本存在一定程度的溶血（定义为溶血指数大于60）。溶血率增加与全血钾浓度升高有关。血钾浓度在6.0至6.9 mEq/L之间的标本中，近60%的溶血指数为100或更高，血钾浓度在7.0 mEq/L或更高的标本中，75%严重溶血（溶血指数为300或更高）。与溶血结果相反，黄疸和脂血对患者结果的影响极小。对于外源性干扰，我们未发现任何水杨酸盐水平升高或服用药用碘化物与全血氯化物分析重叠的患者样本（分别在总共75887次和169229次氯化物测量中）。然而，我们确实发现，在住院环境中接受硝普钠治疗的患者，硝普钠治疗期间全血氯化物浓度[106.7±6.2 mEq/L（均值，标准差）]显著高于硝普钠治疗前或治疗后（103.1±7.7 mEq/L）。
在本次全血标本分析中，溶血是常见干扰因素，可能会像钾分析那样引入有意义的偏差。黄疸、脂血、水杨酸盐和碘化物似乎不太可能导致具有临床意义的偏差。硝普钠治疗使全血氯化物浓度略有升高，可能具有极小的临床意义。
