Clin Lab. 2023 Jul 1;69(7). doi: 10.7754/Clin.Lab.2022.221202.
Platelet transfusions are routinely administered to neonates in intensive care units when there are concerns of bleeding, including high-risk situations like Extracorporeal Membrane Oxygenation (ECMO). Most platelets in ICUs are transfused prophylactically for thrombocytopenia based solely on the platelet count. Platelet Mass Index (PMI) has been proposed as an alternative to platelet count (PC) as a transfusion trigger. The objective of this study was to determine the relationship between PMI and platelet-specific maximal clot firmness (PMCF) in Rotational thromboelastometry (ROTEM), which gives an indication of platelet contribution to clot firmness and to investigate whether PMI may be a better choice as a trigger for platelet transfusions than PC.
Retrospective review of medical records of neonates with congenital heart disease placed on ECMO support in the cardiovascular intensive care unit (CVICU) from 2015 to 2018 was conducted. Platelet count (PC), platelet mean volume (PMV), ROTEM parameters along with demographic data including gestation age, birth weight, gender and survival were collected. Mixed effects linear models with a first order autoregressive covariance structure were used to assess the associations of PMI, PC, and MPV against PMCF. In addition, generalized estimating equations with a first order auto-regressive covariance structure were used to compare odds of transfusion using PC versus PMI triggers.
A total of 92 tests on consecutive days were obtained for 12 ECMO patients (5 male, GA = 38.1 ± 1.6 weeks, BW = 3.1 ± 0.4 kgs, mean ± SD). A variation of 40.1% in PMCF was explained by platelet count (p < 0.001) while 38.5% of the variation in PMCF was explained by PMI (p < 0.001). If the platelet transfusion trigger was PC < 100 x 103 platelets/µL vs. PMI < 800. Using the PC trigger yielded significantly higher odds of transfusion compared to the PMI trigger (odds ratio = 1.31, 95% confidence interval: 1.18 - 1.45, p < 0.001).
While our study failed to demonstrate a superior correlation of PMI with PMCF than PC, our study did reveal that using PMI as transfusion trigger would result in significantly less platelet transfusions, when compared with the current practice of using PC as a trigger.
当有出血风险时，包括体外膜氧合（ECMO）等高危情况，重症监护病房（ICU）中的新生儿通常会接受血小板输注。大多数 ICU 中的血小板是根据血小板计数预防性输注用于治疗血小板减少症。血小板质量指数（PMI）已被提议作为血小板计数（PC）的替代物作为输血触发因素。本研究的目的是确定血小板质量指数（PMI）与旋转血栓弹性测定（ROTEM）中血小板特异性最大凝块硬度（PMCF）之间的关系，ROTEM 可指示血小板对凝块硬度的贡献，并研究血小板质量指数（PMI）是否可以作为比 PC 更好的血小板输注触发因素。
对 2015 年至 2018 年在心血管重症监护病房（CVICU）接受 ECMO 支持的先天性心脏病新生儿的病历进行回顾性分析。收集血小板计数（PC）、血小板平均体积（PMV）、ROTEM 参数以及胎龄、出生体重、性别和存活率等人口统计学数据。使用一阶自回归协方差结构的混合效应线性模型评估 PMI、PC 和 MPV 与 PMCF 的关联。此外，使用一阶自回归协方差结构的广义估计方程比较使用 PC 与 PMI 触发因素进行输血的可能性。
共获得 12 例 ECMO 患者连续 92 天的检测结果（5 名男性，GA=38.1±1.6 周，BW=3.1±0.4kg，平均值±标准差）。血小板计数（PC）可解释 PMCF 变化的 40.1%（p<0.001），而 PMI 可解释 PMCF 变化的 38.5%（p<0.001）。如果血小板输注的触发值为 PC<100x103/µL 与 PMI<800。使用 PC 触发值会比使用 PMI 触发值显著增加输血的可能性（比值比=1.31，95%置信区间：1.18-1.45，p<0.001）。
虽然我们的研究未能证明 PMI 与 PMCF 的相关性优于 PC，但我们的研究确实表明，与目前使用 PC 作为触发因素相比，使用 PMI 作为触发因素会导致血小板输注显著减少。
