Zeroual N, Samarani G, Gallais J, Culas G, Saour M, Mourad M, Gaudard P, Colson P H
Département d'anesthésie réanimation Arnaud de Villeneuve, Centre Hospitalier Régional et Universitaire, Montpellier, France.
PhyMedExp, INSERM U1046, University of Montpellier, Montpellier, France.
Vox Sang. 2018 Feb;113(2):136-142. doi: 10.1111/vox.12610. Epub 2017 Oct 29.
Haemoglobin threshold for transfusion has been significantly decreased, but haemoglobin plasma concentration may not be sufficient to assess the need of red-blood-cell (RBC) transfusion. Central venous oxygen saturation (ScvO ) is a clue of metabolic matching between O transport and consumption, which could help to assess when transfusion is appropriate once anaemia has been diagnosed in ICU patients.
Adult patients admitted consecutively to a cardiothoracic and vascular ICU were included in a prospective, observational and single-centre study over a 6-month period (September 2014 to February 2015), provided they were transfused with RBC. Patients with active bleeding or in unstable condition were excluded. Haemoglobin and ScvO were collected through a central venous catheter before and after transfusion. In order to identify a ScvO threshold, analysis of ScvO changes after transfusion was performed.
Fifty-three patients received 100 RBC transfusions. Haemoglobin at the time of transfusion was 7·2 g/dl [6·8-7·7], while ScvO was 66·9% [60-73]. A 5% increase in ScvO after transfusion has the best specificity and positive predictive values, with a ScvO threshold of 65%. After transfusion (RBC units, 2 [1-2]), ScvO increased only in patients with ScvO ≤65%, from 58% [53-62] to 69% [64-73] (P < 0·001).
In anaemic patients, RBC transfusion induced a significant increase in ScvO , provided it was low before transfusion. A 65% cut-off value of ScvO before transfusion showed good specificity and good positive predictive value for a 5% increase after transfusion.
输血的血红蛋白阈值已显著降低，但血红蛋白血浆浓度可能不足以评估红细胞（RBC）输血需求。中心静脉血氧饱和度（ScvO₂）是氧运输与消耗之间代谢匹配的一个线索，一旦在ICU患者中诊断出贫血，它有助于评估何时进行输血是合适的。
连续入住心胸血管ICU的成年患者纳入一项为期6个月（2014年9月至2015年2月）的前瞻性、观察性单中心研究，条件是他们接受了RBC输血。排除有活动性出血或病情不稳定的患者。在输血前后通过中心静脉导管采集血红蛋白和ScvO₂。为了确定ScvO₂阈值，对输血后ScvO₂的变化进行了分析。
53例患者接受了100次RBC输血。输血时的血红蛋白为7.2 g/dl [6.8 - 7.7]，而ScvO₂为66.9% [60 - 73]。输血后ScvO₂增加5%具有最佳特异性和阳性预测值，ScvO₂阈值为65%。输血后（RBC单位，2 [1 - 2]），仅ScvO₂≤65%的患者ScvO₂升高，从58% [53 - 62]升至69% [64 - 73]（P < 0.001）。
在贫血患者中，RBC输血导致ScvO₂显著升高，前提是输血前ScvO₂较低。输血前ScvO₂的65%临界值对于输血后增加5%显示出良好的特异性和良好的阳性预测值。
