Andrijauskas Audrius, Andrijauskas Povilas, Dilijonas Darius, Jovaiša Tomas, Marozas Vaidotas, Stankevičius Edgaras, Kerroum Axel, Čincikas Darius, Švedienė Saulė, Kvederas Giedrius, Porvaneckas Narūnas, Svensen Christer
Clinic of Anesthesiology and Intensive Care, Institute of Clinical Medicine, Faculty of Medicine, Vilnius University, Vilnius, Lithuania.
II Department of Anesthesiology and Intensive Care, Vilnius University Hospital Santaros Klinikos, Vilnius, Lithuania.
Front Med Technol. 2025 Jul 21;7:1619238. doi: 10.3389/fmedt.2025.1619238. eCollection 2025.
This study evaluates the primary hypothesis of red cell mass (RCM) dependent amplitude of homeostatically acceptable limits of fluctuation in plasma dilution by exploring the correlation between RCM-specific equilibrated hematocrit (EQ_Hct) and amplitude of plasma dilution during perioperative mini Volume Loading Test (mVLT).
We retrospectively analyzed data from our previous RCTs, including 1,651 invasive arterial plasma dilution (aPD), 1,645 noninvasive "capillary" plasma dilution (cPD) and 236 estimates of EQ_Hct from 236 perioperative mVLT sessions. The cPD was estimated using noninvasive hemoglobin (SpHb, Masimo Radical 7, Irvine, CA) measurement. Fixed number of crystalloid boluses was used in 36 and 48 elective total knee arthroplasty (TKA) patients, and individualized number of boluses in 34 total hip arthroplasty (THA) patients for whom the number of boluses depended on the advices by our prototype automated clinical decision support system (ACDSS).
The primary hypothesis was confirmed-aPD decreased as EQ_Hct decreased when EQ_Hct <40%, and a very weak positive correlation was found between EQ_Hct and absolute aPD (Spearman's correlation coefficient 0.1025, < 0.001). It was also confirmed when non-invasive data sets were used. A very weak negative correlation between HctEQ values and absolute cPD values (Spearman's correlation coefficient 0.0640, 0.0149).
This study points to the feasibility of Photoplethysmography (PPG) based estimates of hemoglobin concentration for continuous noninvasive monitoring of fluid accumulation and detecting imminent edema using the Homeostatic Blood States (HBS) theory and transcapillary reflux model. The ACDSS-guided fluid loading has a potential to minimise unnecessary fluid accumulation. Further research is needed to explore and improve these techniques.
本研究通过探讨围手术期小容量负荷试验（mVLT）期间红细胞量（RCM）特异性平衡血细胞比容（EQ_Hct）与血浆稀释幅度之间的相关性，评估血浆稀释中波动的内稳态可接受极限幅度对红细胞量的依赖性这一主要假设。
我们回顾性分析了之前随机对照试验的数据，包括1651例有创动脉血浆稀释（aPD）、1645例无创“毛细血管”血浆稀释（cPD）以及236例围手术期mVLT的EQ_Hct估计值。使用无创血红蛋白（SpHb，Masimo Radical 7，加利福尼亚州欧文市）测量来估计cPD。在36例和48例择期全膝关节置换术（TKA）患者中使用固定数量的晶体推注，在34例全髋关节置换术（THA）患者中使用个体化推注数量，推注数量取决于我们的原型自动临床决策支持系统（ACDSS）的建议。
主要假设得到证实——当EQ_Hct<40%时，aPD随着EQ_Hct的降低而降低，并且在EQ_Hct与绝对aPD之间发现非常弱的正相关（斯皮尔曼相关系数0.1025，P<0.001）。当使用无创数据集时也得到了证实。HctEQ值与绝对cPD值之间存在非常弱的负相关（斯皮尔曼相关系数0.0640，P = 0.0149）。
本研究指出基于光电容积脉搏波描记法（PPG）估计血红蛋白浓度，利用内稳态血液状态（HBS）理论和跨毛细血管反流模型对液体蓄积进行连续无创监测以及检测即将发生的水肿的可行性。ACDSS指导的液体负荷有潜力将不必要的液体蓄积降至最低。需要进一步研究来探索和改进这些技术。
