在线血容量监测评估血液透析患者血容量超负荷诊断指标研究

Diagnostic value of on-line blood volume monitoring in evaluating the blood volume of hemodialystic patients

目的探讨在线血容量监测容量指数（VI）、BVM斜率（BVMS）等指标对血液透析患者容量超负荷的诊断价值。方法选取2011年8月至2012年1月河北医科大学第四医院行维持性血液透析治疗患者49例，临床评估均达到干体重，根据透析后30min生物电阻抗测量结果分为达干体重组（A组）34例和未达干体重组（B组）15例。对B组患者逐渐下调干体重，直至再次测量生物电阻抗结果达正常人群标准时，定为c组（15例）。在透析过程中同时应用在线血容量监测（BVM）观察患者相对血容量变化（ABV）。计算超滤率（UFR）、UFR指数、BVMS、VI等指标。并应用ROC曲线分析计算UFR指数、BVMS、VI在诊断容量超负荷时的曲线下面积，寻找诊断容量超负荷的较好指标。结果除UFR指数外（P〉0．05），其余2项指标B组均低于A组，差异有统计学意义（P〈0．01）。A组与c组比较差异无统计学意义（P〉0．05）。诊断容量超负荷时的曲线下面积为：V10．81（95％C10．67～0．90），BVMS0．79（95％C10．65～0．90），UFR指数0．55（95％C10．40～0．69）。结论VI是诊断是否存在容量超负荷的较好指标，当VI低于0．22时提示水负荷较重，可进一步下调干体重。

Objective To study the diagnostic value of on-line relative blood volume（RBV） in evaluating the volume over- load of hemodialystic patients. Methods We recruited 49 patients （23 males and 26 females）with end-stage renal disease （ESRD） who were on regular maintenance hemodialysis at the blood purification.center of the fourth affiliated hospital of the Hebei Medical University from August 2011 to January 2009. They all reached the DW under the clinical standard. Those 49 patients were divided into two groups based on their post-dialytic total body water（TBW） and the ratio of the extracellular fluid volume and the TBW （ ECW/TBW% ） measured by bioelectricity impedance. Those who met the normal values were designated group A（n = 34） and the others group B（n = 15）. In group B,the DW was lowered by 0. 2 -0. 5 kg per session until the TBW%, ECW/TBW% reached the normal value, defined as group B. Meanwhile, changes in RBV were measured continuously during hemodialysis, using an on-line optical reflection method. Ultrafiltration rate （UFR） , UFR index （UFRI, Uhrafiltration rate divided by the postdialysis weight）, slopes of RBV （RBVS）, volume index （VI, RBV slope corrected for UFR and postdialysis weight）were calculated. The UFRI, RBVS and VI were compared between group A and B, and between group A and B. Using receiver operating characteristic （ ROC ） curve, the areas under curves （AUCs） of the UFRI, BVMS, VI were calculated and compared with each other. Results All indexes except the UFRI were significantly higher in group A than in group B （P 〈 0.01 ）. However, no significant difference was noted between group A and B （P 〉 0. 05）. The results of the AUC were as follows ： VI O. 81 （ 95% CI 0. 67 - 0. 90） 〉 BVMS O. 79 （95% CI 0. 65 - 0. 90） 〉 UFRI 0. 55 （95% CI 0.40 - 0. 69 ）. Conclusion On-line relative blood volume serves as a good marker to monitor volume overload with higher specificity. VI lower than 0. 22 suggests that dry weight canbe further lowered. However;the findings might require studies for validation, and their utility needs to be tested in clinical trials.