Moore Hunter B, Moore Ernest E, Chapman Michael P, Huebner Benjamin R, Einersen Peter M, Oushy Solimon, Silliman Christopher C, Banerjee Anirban, Sauaia Angela
University of Colorado School of Medicine, Aurora, CO University of Colorado School of Public Health, Aurora, CO Denver Health Medical Center, Denver, CO Bonfils Blood Center, Denver, CO.
J Am Coll Surg. 2017 Jul;225(1):138-147. doi: 10.1016/j.jamcollsurg.2017.02.018. Epub 2017 May 15.
Coagulopathy is associated with massive transfusion in trauma, yet most clinical scores to predict this end point do not incorporate coagulation assays. Previous work has identified that shock increases circulating tissue plasminogen activator (tPA). When tPA levels saturate endogenous inhibitors, systemic hyperfibrinolysis can occur. Therefore, the addition of tPA to a patient's blood sample could stratify a patients underlying degree of shock and early coagulation changes to predict progression to massive transfusion. We hypothesized that a modified thrombelastography (TEG) assay with exogenous tPA would unmask patients' impending risk for massive transfusion.
Trauma activations were analyzed using rapid TEG and a modified TEG assay with a low and high dose of tPA. Clinical scores (shock index, assessment of blood consumption, and trauma-associated severe hemorrhage) were compared with TEG measurements to predict the need for massive transfusion using areas under the receiver operating characteristic curves.
Three hundred and twenty-four patients were analyzed, 17% required massive transfusion. Massive transfusion patients had a median shock index of 1.2, assessment of blood consumption score of 1, and trauma-associated severe hemorrhage score of 12. Rapid TEG and tPA TEG parameters were significantly different in all massive transfusion patients compared with non-massive transfusion patients (all p < 0.02). The low-dose tPA lysis at 30 minutes had the largest the area under the receiver operating characteristic curve (0.86; 95% CI 0.79 to 0.93) for prediction of massive transfusion, similar to international normalized ratio of prothrombin time of 0.86 (95% CI 0.81 to 0.91), followed by trauma-associated severe hemorrhage score (0.83; 95% CI 0.77 to 0.89). Combing trauma-associated severe hemorrhage and tPA-TEG variables results in a positive prediction of massive transfusion in 49% of patients with a 98% negative predictive value.
The tPA-TEG identifies trauma patients who require massive transfusion efficiently in a single assay that can be completed in a shorter time than other scoring systems, which has improved performance when combined with international normalized ratio. This new method is consistent with our understanding of the molecular events responsible for trauma-induced coagulopathy.
凝血功能障碍与创伤患者大量输血相关，但大多数预测这一终点的临床评分未纳入凝血检测。既往研究发现，休克会增加循环组织型纤溶酶原激活物（tPA）水平。当tPA水平超过内源性抑制剂时，可发生全身性高纤溶状态。因此，在患者血样中加入tPA可对患者潜在的休克程度和早期凝血变化进行分层，以预测是否会进展为大量输血。我们假设，采用外源性tPA的改良血栓弹力图（TEG）检测可揭示患者即将发生大量输血的风险。
使用快速TEG和采用低剂量及高剂量tPA的改良TEG检测分析创伤激活情况。将临床评分（休克指数、失血评估和创伤相关严重出血）与TEG测量结果进行比较，利用受试者操作特征曲线下面积预测大量输血的需求。
共分析了324例患者，17%的患者需要大量输血。大量输血患者的休克指数中位数为1.2，失血评估评分为1，创伤相关严重出血评分为12。与非大量输血患者相比，所有大量输血患者的快速TEG和tPA-TEG参数均有显著差异（所有p<0.02）。30分钟时低剂量tPA溶解在预测大量输血方面的受试者操作特征曲线下面积最大（0.86；95%CI 0.79至0.93），与凝血酶原时间国际标准化比值0.86（95%CI 0.81至0.91）相似，其次是创伤相关严重出血评分（0.83；95%CI 0.77至0.89）。将创伤相关严重出血和tPA-TEG变量相结合，可对49%的患者进行大量输血的阳性预测，阴性预测值为98%。
tPA-TEG检测可在单次检测中有效识别需要大量输血的创伤患者，且该检测比其他评分系统所需时间更短，与国际标准化比值联合使用时性能更佳。这种新方法与我们对创伤性凝血病相关分子事件的理解一致。
