Department of Surgery, Division of Acute Care Surgery, Carolinas Medical Center, Charlotte, NC.
Department of Orthopedic Surgery, Carolinas Medical Center, Charlotte, NC.
J Am Coll Surg. 2018 Sep;227(3):321-331. doi: 10.1016/j.jamcollsurg.2018.05.005. Epub 2018 Jun 4.
The concept of hemodilution after blood loss and crystalloid infusion is a surgical maxim that remains unproven in humans. We sought to quantify the effect of hemodilution after crystalloid administration in voluntary blood donors as a model for acute hemorrhage.
A prospective, randomized control trial was conducted in conjunction with community blood drives. Donors were randomized to receive no IV fluid (noIVF), 2 liters of normal saline (NS), or 2 liters lactated Ringer's (LR) after blood donation. Blood samples were taken before donation of 500 mL of blood, immediately after donation, and after IV fluid administration. Hemoglobin (Hgb) was measured at each time point. Hemoglobin measurements between time points were compared between groups using standard statistical tests and the Bonferroni correction for multiple comparisons. Statistical significance was set at p ≤ 0.0167.
Of 165 patients consented, 157 patients completed the study. Average pre-donation Hgb was 14.3 g/dL. There was no difference in the mean Hgb levels after blood donation between the 3 groups (p > 0.05). Compared with the control group, there was a significant drop in Hgb in the crystalloid infused groups from the post-donation level to post-resuscitation (13.2 vs 12.1 vs 12.2 g/dL, p < 0.0001). A formula was created to predict hemoglobin levels from a given estimated blood loss (EBL) and volume replacement (VR): Hemodilution Hgb = (mean pre-donation Hgb - hemorrhage Hgb drop - equilibration hemoglobin drop - resuscitation Hgb drop) = Mean pre-donation Hgb - [(EBL/TBV)*l] - [(EBL/TBV)*h] - [(VR/TBV)*r], l = 5.111g/dL = blood loss coefficient, h = 6.722 g/dL = equilibration coefficient, r = 2.617g/dL = resuscitation coefficient.
This study proves the concept of hemodilution and derived a mathematical relationship between blood loss and resuscitation. These data may help to estimate response of hemoglobin levels to blood loss and fluid resuscitation in clinical practice.
失血性和晶体液输注后的血液稀释概念是一种外科手术原则，在人类中尚未得到证实。我们试图通过自愿献血者模型来量化晶体液输注后血液稀释的效果。
在社区献血活动中进行了一项前瞻性、随机对照试验。献血者随机分为不接受静脉补液（noIVF）、接受 2 升生理盐水（NS）或 2 升乳酸林格氏液（LR）。在捐献 500 毫升血液之前、捐献后立即和静脉补液后采集血液样本。在每个时间点测量血红蛋白（Hgb）。使用标准统计检验和 Bonferroni 校正多重比较比较组间的血红蛋白测量值之间的差异。统计学意义设定为 p≤0.0167。
在 165 名同意的患者中，有 157 名患者完成了研究。平均献血前 Hgb 为 14.3g/dL。3 组之间献血后的平均 Hgb 水平无差异（p>0.05）。与对照组相比，晶体液输注组从捐献后水平到复苏后的 Hgb 显著下降（13.2 vs 12.1 vs 12.2 g/dL，p<0.0001）。创建了一个公式来预测给定估计失血量（EBL）和体积置换（VR）的血红蛋白水平：血液稀释 Hgb=（平均献血前 Hgb-出血 Hgb 下降-平衡血红蛋白下降-复苏 Hgb 下降）=平均献血前 Hgb-[(EBL/TBV)*l]-[(EBL/TBV)*h]-[(VR/TBV)*r]，l=5.111g/dL=失血系数，h=6.722g/dL=平衡系数，r=2.617g/dL=复苏系数。
本研究证明了血液稀释的概念，并得出了失血与复苏之间的数学关系。这些数据可能有助于在临床实践中估计血红蛋白水平对失血和液体复苏的反应。
