Department of Anesthesiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
Department of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
J Matern Fetal Neonatal Med. 2022 May;35(10):1969-1977. doi: 10.1080/14767058.2020.1776250. Epub 2020 Jun 10.
To examine the impact of hemodilution on components of blood coagulation using rotational thromboelastometry (ROTEM) in term parturients.
This is a prospective, observational pilot study including 35 healthy, parturients at term (≥37 weeks) without history of bleeding or clotting disorder or on medication affecting coagulation. Venous blood samples were collected and divided into specimen tubes to generate varying degrees of hemodilution with Plasma-Lyte (0%, 20%, 25%, 30%, 35%, 40%, 45%, 55%, 60%, 65%, 70%, 75%, 80%). ROTEM was performed to assess for coagulation changes.
EXTEM (extrinsically activated assay) clotting time (CT) became prolonged at 65% hemodilution and above, and the median CT was in the coagulopathic range (>80 s) at a dilution of 80%. FIBTEM (extrinsically activated assay with platelet inhibitor) amplitude at 5 min (A5) began to diminish at 35% hemodilution, with the median A5 in the coagulopathic range (<12 mm) at 55% hemodilution. The area under the curve (AUC) for EXTEM and FIBTEM consistently declined as hemodilution increased. Greater decreases in FIBTEM AUC were seen compared to EXTEM AUC, with the ratio of FIBTEM:EXTEM AUC at each dilution demonstrating a statistically significant difference from baseline.
All thromboelastometry values demonstrated a hypocoagulable trend as hemodilution increased. However, the samples analyzed by the FIBTEM assay trended toward a coagulopathy at a lower degree of hemodilution compared to the EXTEM assay. As FIBTEM tests analyze the role of fibrinogen in hemostasis and EXTEM tests analyze the role of platelets, our findings suggest that platelets may be able to withstand higher degrees of hemodilution before impairing hemostasis compared to fibrinogen. These findings support the growing body of literature that in early stages of severe obstetric hemorrhage, the prioritization of fibrinogen replacement may be critical in preventing further coagulopathy.
使用旋转血栓弹性测定法（ROTEM）检查足月产妇血液稀释对凝血成分的影响。
这是一项前瞻性、观察性的初步研究，纳入 35 名无出血或凝血障碍病史或无影响凝血药物的健康足月产妇（≥37 周）。采集静脉血样并分成标本管，以生成不同程度的血液稀释，包括 Plasma-Lyte（0%、20%、25%、30%、35%、40%、45%、55%、60%、65%、70%、75%、80%）。进行 ROTEM 以评估凝血变化。
EXTEM（外源性激活检测）凝血时间（CT）在 65%血液稀释及以上时延长，80%稀释时 CT 处于凝血功能障碍范围（>80s）。FIBTEM（血小板抑制剂的外源性激活检测）5 分钟振幅（A5）在 35%血液稀释时开始减少，55%稀释时 A5 处于凝血功能障碍范围（<12mm）。随着血液稀释度的增加，EXTEM 和 FIBTEM 的曲线下面积（AUC）持续下降。与 EXTEM AUC 相比，FIBTEM AUC 的下降幅度更大，每个稀释度的 FIBTEM:EXTEM AUC 比值与基线相比均有统计学意义。
随着血液稀释度的增加，所有血栓弹性测定值均显示出低凝趋势。然而，与 EXTEM 检测相比，FIBTEM 检测分析的纤维蛋白原在较低程度的血液稀释时趋于出现凝血功能障碍。由于 FIBTEM 检测分析纤维蛋白原在止血中的作用，而 EXTEM 检测分析血小板的作用，我们的研究结果表明，与纤维蛋白原相比，血小板在损害止血之前可能能够耐受更高程度的血液稀释。这些发现支持越来越多的文献表明，在严重产科出血的早期阶段，优先考虑纤维蛋白原替代可能对防止进一步凝血功能障碍至关重要。
