不同试管中采集样本的锂含量测定及其储存稳定性的比较评估。

A comparative evaluation of lithium estimation for samples collected in different tubes and its stability on storage.

作者信息

Ikkurthi Saidaiah, Balachander Srinivas, Goyal Bela, Mir Altaf Ahmad, Chakrabarti Subho, Pal Arnab

机构信息

Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India.

Department of Psychiatry, Postgraduate Institute of Medical Education and Research, Chandigarh, India.

出版信息

J Lab Physicians. 2018 Jan-Mar;10(1):56-59. doi: 10.4103/JLP.JLP_78_17.

DOI:10.4103/JLP.JLP_78_17

PMID:29403206

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC5784294/

Abstract

PURPOSE

Lithium (Li) is a well-established drug for the treatment of bipolar affective disorders. Li as a drug is known to possess a narrow therapeutic index. Thus, regular monitoring of blood Li in patients receiving Li therapy is essential. Plain tubes with clot activator are known to interfere with Li estimation. The current study was planned to compare Li estimation in sera from vacutainers with clot activator, and plasma from sodium heparinized vacutainers with that of Li estimation in sera from glass vials. The time-dependant stability of Li estimation on storage at 2°C-8°C for 48 h in these three set of tubes was also evaluated.

MATERIALS AND METHODS

Blood from the patients on Li therapy ( = 100) was collected in 3 different collection tubes: plain vacutainer with clot activator (S), Sodium heparinized vacutainer (P) and Glass vial (G) and was analyzed by ion selective electrode (ISE) analyzer for Li levels. Secondary aliquots were also taken from each type of collection tube and stored at 2°C-8°C. Time-dependant stability of Li estimation was checked at 12 h, 24 h, and 48 h. ANOVA followed by Tukey's posttest was performed to calculate statistical significance taking glass vial as reference collection tube. Bland-Altman plots were plotted to compare between three collection tubes at baseline. Stability on storage was defined when >95% of the samples were within allowable error limit for that time point taking baseline levels as reference.

RESULTS

A mean bias of 0.18 mmol/L and mean percentage bias of 19.9% in Li levels was observed between serum from (S) than serum from (G). This difference was found to be statistically significant. However, statistically nonsignificant mean bias of 0.02 mmol/L and mean percentage bias of 3.34% in Li levels was observed between plasma from (P) and serum from (G). Time-dependant stability was observed more in glass vials as compared to vacutainers with clot activator or sodium heparin.

CONCLUSION

Serum from glass vial should be the preferred method for blood collection to determine Li levels.

摘要

目的

锂（Li）是治疗双相情感障碍的一种成熟药物。已知锂作为一种药物具有较窄的治疗指数。因此，对接受锂治疗的患者定期监测血锂至关重要。已知含促凝剂的普通试管会干扰锂的测定。本研究旨在比较含促凝剂的真空采血管中的血清、肝素钠抗凝真空采血管中的血浆与玻璃小瓶中的血清的锂测定结果。还评估了这三组试管中的锂测定结果在2°C - 8°C储存48小时的时间依赖性稳定性。

材料与方法

从100名接受锂治疗的患者采集血液，分别收集于3种不同的采血管中：含促凝剂的普通真空采血管（S）、肝素钠抗凝真空采血管（P）和玻璃小瓶（G），并通过离子选择性电极（ISE）分析仪分析锂水平。每种采血管还取二次等分样本并储存于2°C - 8°C。在12小时、24小时和48小时检查锂测定结果的时间依赖性稳定性。以玻璃小瓶作为参考采血管，采用方差分析（ANOVA）及Tukey事后检验计算统计学显著性。绘制Bland - Altman图以比较三个采血管在基线时的情况。当以基线水平为参考，>95%的样本在该时间点的允许误差范围内时，定义为储存稳定性。

结果

观察到（S）组血清的锂水平与（G）组血清相比，平均偏差为0.18 mmol/L，平均百分比偏差为19.9%。发现这种差异具有统计学显著性。然而，观察到（P）组血浆与（G）组血清的锂水平平均偏差为0.02 mmol/L，平均百分比偏差为3.34%，差异无统计学显著性。与含促凝剂的真空采血管或肝素钠相比，玻璃小瓶中观察到的时间依赖性稳定性更高。