Department of Anesthesia, Critical Care and Pain Medicine, Division of General Anesthesia and Intensive Care Medicine, Medical University of Vienna, 1090, Vienna, Austria.
Department of Statistics und Operations Research, University of Vienna, 1090, Vienna, Austria.
Pediatr Res. 2021 Aug;90(2):452-458. doi: 10.1038/s41390-020-01310-8. Epub 2020 Dec 18.
Thrombelastometry, allowing timely assessment of global hemostatic function, is increasingly used to guide hemostatic interventions in bleeding patients. Reference values are available for adults and children, including infants but not neonates immediately after birth.
Neonates were grouped as preterm (30 + 0 to 36 + 6 weeks/days) and term (37 + 0 to 39 + 6 weeks/days). Blood samples were drawn from the umbilical cord immediately after cesarean section and analyzed by thrombelastometry. Reference ranges were determined for the extrinsic and intrinsic coagulation pathways, fibrin polymerization, and hyperfibrinolysis detection.
All extrinsically activated test parameters, but maximum lysis (P = 0.139) differed significantly between both groups (P ≤ 0.001). Maximum clot firmness in the fibrin polymerization test was comparable (P = 0.141). All intrinsically activated test parameters other than coagulation time (P = 0.537) and maximum lysis (P = 0.888) differed significantly (P < 0.001), and so did all aprotinin-related test parameters (P ≤ 0.001) but maximum lysis (P = 0.851).
This is the first study to identify reference ranges for thrombelastometry in preterm and term neonates immediately after birth. We also report differences in clot initiation and clot strength in neonates born <37 versus ≤40 weeks of gestation, mirroring developmental hemostasis.
Impact: This prospective observational study is the first to present reference ranges in preterm and term infants for all types of commercially available tests of thrombelastometry, notably also including the fibrin polymerization test.
Viscoelastic coagulation assays such as thrombelastometry have become integral to the management of perioperative bleeding by present-day standards. Reference values are available for adults, children, and infants but not for neonates. Key message: Clot initiation and formation was faster and clot strength higher in the term than in the preterm group. Parameters of thrombelastometry obtained from cord blood do not apply interchangeably to preterm and term neonates.
血栓弹力描记术能够及时评估整体止血功能，正越来越多地用于指导出血患者的止血干预。目前已有成人和儿童的参考值，包括出生后立即的婴儿，但不包括新生儿。
新生儿分为早产儿（30+0 至 36+6 周/天）和足月儿（37+0 至 39+6 周/天）。剖宫产术后立即从脐静脉取血，通过血栓弹力描记术进行分析。确定了外源性和内源性凝血途径、纤维蛋白聚合和纤维蛋白溶解检测的参考范围。
所有外源性激活的测试参数，除最大纤溶（P=0.139）外，两组间差异均有统计学意义（P≤0.001）。纤维蛋白聚合试验中最大凝块硬度无差异（P=0.141）。内源性激活的所有测试参数，除凝血时间（P=0.537）和最大纤溶（P=0.888）外，差异均有统计学意义（P<0.001），以及所有抑肽酶相关的测试参数（P≤0.001）但最大纤溶（P=0.851）。
这是第一项研究，确定了出生后立即的早产儿和足月儿的血栓弹力描记术参考范围。我们还报告了胎龄<37 周与≤40 周的新生儿之间的凝块起始和凝块强度差异，反映了发育性止血。
这项前瞻性观察研究是第一项为所有类型的商业血栓弹力描记术提供参考范围的早产儿和足月儿研究，特别是还包括纤维蛋白聚合试验。
目前，弹性凝血检测如血栓弹力描记术已成为围手术期出血管理的重要组成部分。已有成人、儿童和婴儿的参考值，但没有新生儿的参考值。主要发现：与早产儿相比，足月儿的凝块起始和形成更快，凝块强度更高。脐带血中获得的血栓弹力描记术参数不能相互替代早产儿和足月儿。
