Lindsay Robert M, Shulman Tanya, Prakash Suma, Nesrallah Gihad, Kiaii Mercedeh
Optimal Dialysis Research Unit, London Health Sciences Center and The University of Western Ontario, London, Ontario, Canada.
Hemodial Int. 2003 Jun 1;7(3):204-8. doi: 10.1046/j.1492-7535.2003.00041.x.
Volume overload is a factor in the hypertension of hemodialysis (HD) patients. Fluid removal is therefore integral to the hemodialysis treatment. Fluid removal by hemodialysis ultrafiltration (UF) may cause intradialytic hypotension and leg cramps. Understanding blood pressure (BP) and volume changes during UF may eliminate intradialytic hypotension and cramps. Studies (S1, S2, and S3) were carried out to determine the amount and direction of changes in body fluid compartments following UF and to determine the relationships between BP, changes in blood volume (DeltaBV), central blood volume (CBV), cardiac output (CO), peripheral vascular resistance (PVR) plus total body water (TBW), and intra- and extracellular fluid volumes (ICF, ECF) in both the whole body and body segments (arms, legs, trunk).
Indicator dilution technology (Transonic) was used for CBV, CO, and PVR; hematocrit monitoring (Crit-Line) was used for DeltaBV segmental bioimpedance (Xitron) for TBW, ICF, and ECF.
S1 (n = 21) showed UF sufficient to cause DeltaBV of -7% and lead to minor changes (same direction) in CBV and CO, and with cessation of UF, vascular refilling was preferential to CBV. S2 (n = 20) showed that predialysis HD patients are ECF-expanded (ECF/ICF ratio = 0.96, controls = 0.74 [P < 0.0001]) and BP correlates with ECF (r = 0.47, P = 0.35). UF to cause DeltaBV of -7% was associated with a decrease in ECF (P < 0.0001) and BP directly (r = 0.46, P = 0.04) plus DeltaBV indirectly (r = -0.5, P = 0.024) correlated with PVR, while CBV and CO were maintained. S3 (n = 11) showed that following UF, total-body ECF changes were correlated with leg ECF (r = 0.94) and arm ECF (r = 0.72) but not trunk ECF. Absolute ECF reduction was greatest from the legs.
Predialysis ECF influences BP and UF reduces DeltaBV and ECF, but CBV and BP are conserved by increasing PVR. ECF reduction is mainly from the legs, hence may cause cramps. Intradialytic hypotension is caused by failure of PVR response.
容量超负荷是血液透析（HD）患者高血压的一个因素。因此，液体清除是血液透析治疗的重要组成部分。通过血液透析超滤（UF）进行液体清除可能会导致透析过程中的低血压和腿部痉挛。了解超滤过程中的血压（BP）和容量变化可能会消除透析过程中的低血压和痉挛。开展了研究（S1、S2和S3）以确定超滤后体液 compartments 的变化量和方向，并确定全身及身体各部位（手臂、腿部、躯干）的血压、血容量变化（ΔBV）、中心血容量（CBV）、心输出量（CO）、外周血管阻力（PVR）加上总体水（TBW）以及细胞内和细胞外液体积（ICF、ECF）之间的关系。
使用指示剂稀释技术（Transonic）测量CBV、CO和PVR；使用血细胞比容监测（Crit-Line）测量ΔBV，使用分段生物电阻抗（Xitron）测量TBW、ICF和ECF。
S1（n = 21）显示超滤足以导致ΔBV降低7%，并使CBV和CO发生轻微变化（方向相同），并且在超滤停止后，血管再充盈优先于CBV。S2（n = 20）显示透析前HD患者的ECF扩张（ECF/ICF比值 = 0.96，对照组 = 0.74 [P < 0.0001]），并且血压与ECF相关（r = 0.47，P = 0.35）。导致ΔBV降低7%的超滤与ECF的降低相关（P < 0.0001），并且血压直接相关（r = 0.46，P = 0.04），加上ΔBV间接与PVR相关（r = -0.
