Pappachan Liby G, Williams Aparna, Sebastian Tunny, Korula Grace, Singh Georgene
Department of Anesthesiology, Christian Medical College, Vellore, Tamil Nadu, India.
J Anaesthesiol Clin Pharmacol. 2019 Jan-Mar;35(1):99-105. doi: 10.4103/joacp.JOACP_304_17.
The aim of the study was to observe the trends in central venous oxygen saturation (ScvO), lactate, and ST segment changes with change in hemoglobin in patients undergoing acute blood loss during surgery and to assess their role as blood transfusion trigger.
Seventy-seven consecutive patients undergoing craniotomy at a tertiary care institution were recruited for this study after obtaining written, informed consent. After establishing standard monitoring, anesthesia was induced with standard anesthetic protocol. Hemodynamic parameters such as heart rate, blood pressure (mean, systolic, diastolic), pulse pressure variation (PPV), and physiological parameters such as lactate, ScvO, ST segment changes were checked at baseline, before and after blood transfusion and at the end of the procedure.
Comparison of the mean and standard deviation for the hemodynamic parameters was performed between the transfused and nontransfused patient groups. Pearson correlation test was done to assess the correlation between the covariates. Receiver operating characteristic (ROC) curve was constructed for the ScvO variable, which was used as a transfusion trigger and the cutoff value at 100% sensitivity and 75% specificity was constructed. Linear regression analysis was done between the change in hemoglobin and the change in ScvO and change in hemoglobin and change in the ST segment.
There was a statistically significant positive correlation between the change in ScvO and change in hemoglobin during acute blood loss with a regression coefficient of 0.8 and also between change in ST segment and hemoglobin with a regression coefficient of -0.132. No significant change was observed with lactate. The ROC showed a ScvO cutoff of 64.5% with a 100% sensitivity and 75% specificity with area under curve of 0.896 for blood transfusion requirement.
We conclude that ScvO and ST change may be considered as physiological transfusion triggers in patients requiring blood transfusion in the intraoperative period.
本研究旨在观察手术中急性失血患者的中心静脉血氧饱和度（ScvO）、乳酸水平及ST段变化随血红蛋白变化的趋势，并评估它们作为输血触发指标的作用。
在一家三级医疗机构，经书面知情同意后，连续纳入77例接受开颅手术的患者进行本研究。建立标准监测后，采用标准麻醉方案诱导麻醉。在基线、输血前后及手术结束时检查血流动力学参数，如心率、血压（平均压、收缩压、舒张压）、脉压变异（PPV），以及生理参数，如乳酸、ScvO、ST段变化。
对输血组和未输血组患者的血流动力学参数均值和标准差进行比较。采用Pearson相关检验评估协变量之间的相关性。构建ScvO变量的受试者工作特征（ROC）曲线，将其用作输血触发指标，并确定100%敏感性和75%特异性时的截断值。对血红蛋白变化与ScvO变化以及血红蛋白变化与ST段变化进行线性回归分析。
急性失血期间，ScvO变化与血红蛋白变化之间存在统计学显著正相关，回归系数为0.8；ST段变化与血红蛋白之间也存在显著相关性，回归系数为-0.132。乳酸水平未见显著变化。ROC曲线显示，输血需求的ScvO截断值为64.5%，敏感性为100%，特异性为75%，曲线下面积为0.896。
我们得出结论，对于术中需要输血的患者，ScvO和ST段变化可被视为生理性输血触发指标。
