Patil Parag, Sehgal Tushar, Goswami Priyanka, Gaur Malvika, Khan Maroof, Pandey Shivam, Datta Sudip K
Laboratory Medicine, All India Institute of Medical Sciences, New Delhi, New Delhi, IND.
Biostatistics, All India Institute of Medical Sciences, New Delhi, New Delhi, IND.
Cureus. 2022 Jan 15;14(1):e21268. doi: 10.7759/cureus.21268. eCollection 2022 Jan.
Background In this study, we aimed to determine the effects of storage time and temperature on commonly performed coagulation tests such as prothrombin time (PT), international normalized ratio (INR), and activated partial thromboplastin time (APTT) in human plasma. Methodology Whole blood samples from 100 patients were collected in a 3.2% sodium citrate vacutainer. The blood was centrifuged within two hours of collection at 2,000 g for 10 minutes, and the platelet-poor plasma (PPP) obtained was analyzed for PT, INR, and APTT tests at zero hours (baseline) and repeated at 12 hours, 24 hours, and 36 hours on a fully automated coagulation analyzer at various storage conditions (room temperature, refrigerator, and freezer). The results were categorized into two groups: group 1 comprised results with normal coagulation profile and group 2 comprised results with abnormal coagulation profile. The percentage change of the results from baseline (zero hours) for PT, INR, and APTT tests was also studied. A percentage change of more than ±10% from baseline was considered as a clinically significant change. Results In this study, a total of 95 PPP samples were evaluated. The median age of all patients was 44 years (range: 19-65 years). The male-to-female ratio was 0.9:1. The baseline PT, INR, and APTT values were 12.1 seconds, 1.06, and 26.5 seconds, respectively, in group 1, whereas the baseline PT, INR, and APTT values were 19.1 seconds, 1.80, and 36.0 seconds, respectively, in group 2. In the freezer, the samples were stable for PT, INR, and APTT tests at 12 hours, 24 hours, and 36 hours showing a change of <10% from baseline at all three time-points. In the refrigerator, the samples were stable for PT and INR tests for up to 24 hours showing a change of <10% from baseline. In comparison, the samples for the APTT test were not stable at 12 hours, 24 hours, and 36 hours showing a change of 12.1%, 15.5%, and 17.9%, respectively, from the baseline (zero hours). Finally, at room temperature, the samples deteriorated at 12 hours for all coagulation parameters (PT, INR, and APTT). Conclusions The patient plasma samples for PT, INR, and APTT tests could be safely stored for up to 36 hours in the freezer. In the refrigerator, samples for PT and INR tests could be safely stored for up to 24 hours while the samples for APTT deteriorated at 12 hours. All patient samples for PT, INR, and APTT tests deteriorated at 12 hours at room temperature.
背景 在本研究中，我们旨在确定储存时间和温度对人血浆中常用凝血试验的影响，如凝血酶原时间（PT）、国际标准化比值（INR）和活化部分凝血活酶时间（APTT）。
方法 从100名患者采集的全血样本收集于含有3.2%柠檬酸钠的真空采血管中。血液在采集后两小时内以2000g离心10分钟，所得乏血小板血浆（PPP）在零时（基线）进行PT、INR和APTT检测，并在不同储存条件（室温、冰箱和冷冻箱）下于12小时、24小时和36小时在全自动凝血分析仪上重复检测。结果分为两组：第1组为凝血谱正常的结果，第2组为凝血谱异常的结果。还研究了PT、INR和APTT检测结果相对于基线（零时）的百分比变化。相对于基线变化超过±10%被认为具有临床显著变化。
结果 在本研究中，共评估了95份PPP样本。所有患者的中位年龄为44岁（范围：19 - 65岁）。男女比例为0.9:1。第1组基线PT、INR和APTT值分别为12.1秒、1.06和26.5秒，而第2组基线PT、INR和APTT值分别为19.1秒、1.80和36.0秒。在冷冻箱中，样本在12小时、24小时和36小时的PT、INR和APTT检测中保持稳定，在所有三个时间点相对于基线的变化均<10%。在冰箱中，样本在PT和INR检测中稳定长达24小时，相对于基线的变化<10%。相比之下，APTT检测的样本在12小时、24小时和36小时不稳定，相对于基线（零时）的变化分别为12.1%、15.5%和17.9%。最后，在室温下，所有凝血参数（PT、INR和APTT）的样本在12小时时变质。
结论 用于PT、INR和APTT检测的患者血浆样本可在冷冻箱中安全储存长达36小时。在冰箱中，PT和INR检测的样本可安全储存长达24小时，而APTT检测的样本在12小时时变质。所有用于PT、INR和APTT检测的患者样本在室温下12小时时均变质。
