Madsen Daniel E, Ingerslev Janne, Sidelmann Johannes J, Thorn Jens J, Gram Jørgen
Unit for Thrombosis Research, Institute of Public Health, University of Southern Denmark, Esbjerg, Denmark.
J Oral Maxillofac Surg. 2012 Oct;70(10):e547-52. doi: 10.1016/j.joms.2012.06.182.
The aim of this prospective study was to evaluate the predictive value of the viscoelastic properties of whole blood samples collected preoperatively in relation to intraoperative blood loss in patients subjected to orthognathic surgery.
Forty-one consecutive patients underwent simultaneous mandibular and maxillary osteotomy. Whole blood samples were collected preoperatively. The intraoperative blood loss volume was precisely estimated. The viscoelastic properties of whole blood samples were evaluated by thromboelastography (TEG), a global method that addresses the complex interplay among coagulation factors, blood platelets, and components of the fibrinolytic system. Blood platelet count, activated partial thromboplastin time, prothrombin time, plasma fibrinogen concentration, and D-dimer concentration were determined by routine methods.
Patients were separated into 2 groups according to their intraoperative bleeding volume (≤ 400 mL and >400 mL). No significant associations were observed between routine coagulation tests and intraoperative bleeding volume. The TEG results for the groups were compared. Significant associations were observed between intraoperative blood loss and the clot formation time, maximum clot firmness, and α angle, whereas bleeding volume was not related to the fibrinolytic resistance of the blood clot. An α angle exceeding 67° predicted with 95% certainty a blood loss of 400 mL or less.
We conclude that intraoperative bleeding volume in patients subjected to orthognathic surgery can be predicted by means of preoperative TEG analysis. TEG results provide optimization of patient safety and can be used for the evaluation of bleeding risk.
本前瞻性研究的目的是评估正颌手术患者术前采集的全血样本的粘弹性特性与术中失血的预测价值。
41例连续患者同时接受下颌骨和上颌骨截骨术。术前采集全血样本。精确估计术中失血量。通过血栓弹力图（TEG）评估全血样本的粘弹性特性，TEG是一种全面评估凝血因子、血小板和纤维蛋白溶解系统各成分之间复杂相互作用的方法。通过常规方法测定血小板计数、活化部分凝血活酶时间、凝血酶原时间、血浆纤维蛋白原浓度和D-二聚体浓度。
根据术中出血量（≤400 mL和>400 mL）将患者分为两组。常规凝血试验与术中出血量之间未观察到显著相关性。比较两组的TEG结果。术中失血与凝血形成时间、最大凝血强度和α角之间存在显著相关性，而出血量与血凝块的纤维蛋白溶解抗性无关。α角超过67°可95%确定地预测失血量为400 mL或更少。
我们得出结论，正颌手术患者的术中出血量可通过术前TEG分析进行预测。TEG结果可优化患者安全性，并可用于评估出血风险。
