Saw Jacqueline, Kereiakes Dean J, Mahaffey Kenneth W, Applegate Robert J, Braden Gregory A, Brent Bruce N, Brodie Bruce R, Groce James B, Levine Glenn N, Leya Fred, Moliterno David J
Department of Cardiovascular Medicine, The Cleveland Clinic Foundation, Cleveland, OH, USA.
Thromb Res. 2003;112(5-6):301-6. doi: 10.1016/j.thromres.2004.01.006.
Measurement of enoxaparin's anticoagulant activity has been limited to specialized coagulation laboratories and has been impractical for areas needing rapid results, such as during coronary angioplasty. A new point-of-care device, Rapidpoint ENOX, was recently developed to measure clotting times with enoxaparin use.
To correlate ENOX times with anti-Xa levels among patients receiving enoxaparin.
A total of 166 patients receiving enoxaparin for the prevention of deep venous thrombosis or as treatment during acute coronary syndromes or angioplasty were prospectively studied. Citrated and non-citrated whole-blood (CWB and NCWB) samples were obtained at baseline and peak enoxaparin activity. ENOX times were measured with whole-blood, and the Stachrom anti-Xa assay was performed on the plasma from the remainder of the samples. The Pearson correlation coefficient was used to assess the relationship between these two assays.
There was a strong linear correlation between the ENOX times and the anti-Xa activities for both CWB (r=0.89, p<0.001) and NCWB (r=0.82, p<0.001) when considering all 332 samples (baseline and peak). When baseline samples were excluded, the correlation remained strong for CWB ENOX times and anti-Xa levels (r=0.84, p<0.001), but was only moderate for NCWB (r=0.73, p<0.001). A CWB ENOX time of </=160 s corresponded to anti-Xa level of </=0.5 IU/ml in 95% (188/197) of patients. A CWB ENOX time >/=200 s corresponded to anti-Xa levels >/=0.8 IU/ml in 96% (93/96) of patients.
Rapidpoint ENOX times correlate strongly to anti-Xa activities measured by the Stachrom Heparin Assays for citrated whole-blood samples. This novel test can be used for rapid bedside measurements of enoxaparin anticoagulant activity.
依诺肝素抗凝活性的检测一直局限于专业的凝血实验室，对于需要快速出结果的情况（如冠状动脉血管成形术期间）并不实用。最近研发了一种即时检验设备Rapidpoint ENOX，用于检测使用依诺肝素时的凝血时间。
在接受依诺肝素治疗的患者中，将ENOX时间与抗Xa水平进行相关性分析。
前瞻性研究了166例接受依诺肝素预防深静脉血栓形成或作为急性冠状动脉综合征或血管成形术治疗用药的患者。在基线和依诺肝素活性峰值时采集枸橼酸化全血（CWB）和非枸橼酸化全血（NCWB）样本。用全血检测ENOX时间，对其余样本的血浆进行Stachrom抗Xa检测。采用Pearson相关系数评估这两种检测方法之间的关系。
在考虑所有332个样本（基线和峰值）时，CWB（r = 0.89，p < 0.001）和NCWB（r = 0.82，p < 0.001）的ENOX时间与抗Xa活性之间均存在强线性相关性。排除基线样本后，CWB的ENOX时间与抗Xa水平之间的相关性仍然很强（r = 0.84，p < 0.001），但NCWB的相关性仅为中等（r = 0.73，p < 0.001）。95%（188/197）的患者CWB的ENOX时间≤160秒对应抗Xa水平≤0.5 IU/ml。96%（93/96）的患者CWB的ENOX时间≥200秒对应抗Xa水平≥0.8 IU/ml。
对于枸橼酸化全血样本，Rapidpoint ENOX时间与通过Stachrom肝素检测法测得的抗Xa活性密切相关。这种新型检测方法可用于床边快速检测依诺肝素的抗凝活性。
