Department of General Surgery and Radiology, Pirogov Russian National Research Medical University, Moscow, Russian Federation.
Department of General Surgery and Radiology, Pirogov Russian National Research Medical University, Moscow, Russian Federation.
J Vasc Surg Venous Lymphat Disord. 2020 Jan;8(1):31-41. doi: 10.1016/j.jvsv.2019.06.015. Epub 2019 Sep 5.
The thrombodynamic test (TD) is a novel global test of hemostasis that allows to study the spatial-temporal characteristics of a clot formation in real time under conditions close to natural ones and demonstrates high sensitivity to detect the state of hypercoagulation. The main paraments of the test are the velocity of clot growth, clot's size, and clot density. The objective of this study was to compare the classic Caprini 2005 score and its modified version in association with the results of TD. The goal is to predict postoperative venous thromboembolism (VTE) in surgical patients undergoing surgery for colorectal cancer.
This was a prospective observational clinical study involving 80 patients (33 men and 47 women; mean age, 73.9 ± 7.2 years) who underwent major (79 cases) or minor (1 case) surgery for colorectal cancer. Patients were at high risk for postoperative VTE (ie, a mean Caprini score of 9.9 ± 2.0) and received combined prophylaxis (ie, antiembolic compression stockings and enoxaparin 40 mg once daily) until discharge. Enoxaparin was administered at a fixed time of blood sampling for the TD test. Duplex ultrasound scan was performed to detect postoperative vein thrombosis before and 5 to 7 days after surgery.
Postoperative vein thrombosis was found in 21 of 80 patients (26.3%; 95% confidence interval, 17.9%-36.8%). Regression analysis and receiver operating characteristic (ROC) curve showed that Caprini scores significantly predicted VTE (P < .0001; area under the curve [AUC] = 0.839 ± 0.045). Analysis of ROC curve coordinates showed that a cutoff point of 11 scores had a sensitivity of 76.2% and a specificity of 74.6%. The results of the TD test showed significant hypercoagulation despite enoxaparin administration in patients with VTE. Regression analysis and ROC curves demonstrated that the following TD parameters had the greatest predictability for postoperative DVT: initial velocity of clot growth (Vin) and clot size (CS) measured at 12 hours after enoxaparin administration (AUC, 0.697 ± 0.063 and AUC, 0.790 ± 0.059, respectively), as well as Vin and CS measured 24 hours after the enoxaparin injection (S = 0.847 ± 0.059 and S = 0.803 ± 0.069, respectively). The cutoff points for VTE prediction at 12 and 24 hours seemed to be a Vin of greater than 62.5 and greater than 64.5 μm/minute (normal range, 35-56 μm/minute) as well as a CS of greater than 1351.5 and greater than 1333.5 μm (normal range, 800-1200 μm), respectively. Identified thresholds for TD parameters have been integrated into Caprini scores under the item "other congenital or acquired thrombophilia." The total Caprini scores were recalculated in patients where one or all TD parameters had exceeded the cutoff followed by reanalysis of the ROC curves. The best predictability was found for Caprini scores considering the elevation of all four TD parameters (AUC, 0.924 ± 0.029) with increased cutoff to a score of 12 with a sensitivity of 85.7% and a specificity of 81.4%. The use of cutoffs for the original and modified scores could be used to calculate the number of patients that were under cutoff but developed with VTE: 10.2% and 5.9%, respectively.
Integrating TD parameters into the Caprini score increases the ability to predict postoperative VTE.
血栓动力测试（TD）是一种新的止血整体测试，允许在接近自然的条件下实时研究血凝块形成的时空特征，并表现出对高凝状态的高敏感性。该测试的主要参数是凝块生长速度、凝块大小和凝块密度。本研究的目的是比较经典的卡普里尼 2005 评分及其改良版与 TD 结果的关联。目标是预测接受结直肠癌手术的外科患者术后静脉血栓栓塞症（VTE）。
这是一项前瞻性观察性临床研究，涉及 80 名患者（33 名男性和 47 名女性；平均年龄 73.9±7.2 岁），他们接受了结直肠癌的主要（79 例）或次要（1 例）手术。患者术后 VTE 风险高（即平均卡普里尼评分 9.9±2.0），接受联合预防治疗（即抗栓塞压缩袜和依诺肝素 40mg 每日一次），直到出院。在 TD 测试时进行固定时间的采血，以进行依诺肝素给药。在手术后 5 至 7 天，使用双功超声扫描检测术后静脉血栓形成。
80 名患者中有 21 名（26.3%；95%置信区间，17.9%-36.8%）发现术后静脉血栓形成。回归分析和接收者操作特征（ROC）曲线显示卡普里尼评分显著预测 VTE（P<0.0001；曲线下面积[AUC]为 0.839±0.045）。ROC 曲线坐标分析表明，截断值为 11 分时，敏感性为 76.2%，特异性为 74.6%。TD 测试结果显示，尽管给予依诺肝素，患者仍存在明显的高凝状态。回归分析和 ROC 曲线表明，以下 TD 参数对术后 DVT 具有最大的预测能力：依诺肝素给药后 12 小时测量的初始凝块生长速度（Vin）和凝块大小（CS）（AUC 分别为 0.697±0.063 和 AUC 为 0.790±0.059），以及依诺肝素注射后 24 小时测量的 Vin 和 CS（S 分别为 0.847±0.059 和 S 为 0.803±0.069）。在 12 和 24 小时时的 VTE 预测截断值似乎为大于 62.5 和大于 64.5μm/min 的 Vin 以及大于 1351.5 和大于 1333.5μm 的 CS（正常范围为 35-56μm/min 和 800-1200μm）。确定的 TD 参数阈值已在“其他先天性或获得性血栓形成倾向”项目下纳入卡普里尼评分。在一个或所有 TD 参数超过截断值的患者中重新计算总卡普里尼评分，然后重新分析 ROC 曲线。考虑到所有四个 TD 参数升高的卡普里尼评分具有最佳的预测性（AUC，0.924±0.029），增加到 12 的截断值，敏感性为 85.7%，特异性为 81.4%。使用原始和改良评分的截止值可以用于计算处于截止值以下但发生 VTE 的患者数量：分别为 10.2%和 5.9%。
将 TD 参数纳入卡普里尼评分可提高预测术后 VTE 的能力。
