Department of Pathology, University of Virginia Health System, Charlottesville, VA.
Department of Pharmacy, University of Virginia Health System, Charlottesville, VA.
J Appl Lab Med. 2021 Mar 1;6(2):378-386. doi: 10.1093/jalm/jfaa084.
When monitoring heparin, anti-Xa assays are susceptible to interference from apixaban taken before admission and can result in inappropriate dose adjustments that can negatively affect patient care.
We derived a novel assay, termed corrected heparin (CH), using quantified values from a chromogenic anti-Xa assay with heparin calibrators before and after heparinase treatment to eliminate any interference from apixaban within the patient sample. We retrospectively assessed 469 specimens from 72 patients at our institution who had their unfractionated heparin infusion monitored using the CH assay because of known apixaban use. These patients were included in the study if they had detectable apixaban levels (>0.1 IU/mL by anti-Xa).
The analytical performance of the assay was evaluated, and precision was found to be 8.8% within 1 day and 13.3% over multiple days, with acceptable linearity (R2 = 0.997). Evaluation of clinical performance was compared with the partial thromboplastin time (PTT), showing a lack of correlation similar to comparisons between the PTT and anti-Xa assay (Blood Coagul Fibrinolysis 1993;4:635-8). The mean time to a therapeutic result in this cohort was 10 hours and 10 minutes. The CH assay was used to determine how long the apixaban was detected by the anti-Xa assay. The majority of patients (80%) still had measurable anti-Xa assay interference from apixaban at 24 hours after the last apixaban dose.
We have developed and evaluated an assay capable of quantifying heparin in the presence of apixaban. This assay showed acceptable performance in both analytical and clinical performance.
在监测肝素时，抗 Xa 检测法容易受到入院前使用的阿哌沙班的干扰，可能导致不适当的剂量调整，从而对患者治疗产生负面影响。
我们使用经过肝素酶处理前后的显色抗 Xa 检测法中定量值，衍生出一种新的检测方法，称为校正肝素（CH），以消除患者样本中阿哌沙班的任何干扰。我们回顾性评估了我们机构的 72 名患者的 469 份样本，这些患者因已知使用阿哌沙班而使用 CH 检测法监测未分级肝素输注。如果这些患者的阿哌沙班水平可检测（抗 Xa 检测>0.1 IU/mL），则将其纳入本研究。
评估了该检测法的分析性能，发现日内精密度为 1 天内 8.8%，多日内 13.3%，线性度可接受（R2=0.997）。与部分凝血活酶时间（PTT）的临床性能评估相比，与 PTT 与抗 Xa 检测法之间的比较相似，相关性不佳。该队列的平均治疗结果时间为 10 小时 10 分钟。使用 CH 检测法确定抗 Xa 检测法仍能检测到阿哌沙班的时间。大多数患者（80%）在最后一次阿哌沙班剂量后 24 小时仍存在可测量的抗 Xa 检测法干扰。
我们已经开发并评估了一种能够在存在阿哌沙班的情况下定量检测肝素的检测法。该检测法在分析和临床性能方面均表现出可接受的性能。
