Susantitaphong Paweena, Laowaloet Suthanit, Tiranathanagul Khajohn, Chulakadabba Adhisabandh, Katavetin Pisut, Praditpornsilpa Kearkiat, Tungsanga Kriang, Eiam-Ong Somchai
Division of Nephrology, Department of Medicine, King Chulalongkorn Memorial Hospital, Thai Red Cross and Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
Ther Apher Dial. 2013 Feb;17(1):9-15. doi: 10.1111/j.1744-9987.2012.01136.x. Epub 2012 Dec 11.
Chronic volume overload resulting from interdialytic weight gain and inadequate fluid removal plays a significant role in poorly controlled high blood pressure. Although bioimpedance has been introduced as an accurate method for assessing hydration status, the instrument is not available in general hemodialysis (HEMO) centers. This study was conducted to explore the correlation between hydration status measured by bioimpedance and blood pressure parameters in chronic HEMO patients. Multifrequency bioimpedance analysis was used to determine pre- and post-dialysis hydration status in 32 stable HEMO patients. Extracellular water/total body water (ECW/TBW) determined by sum of segments from bioimpedance analysis was used as an index of hydration status. The mean age was 57.9 ± 16.4 years. The mean dry weight and body mass index were 57.7 ± 14.5 kg and 22.3 ± 4.7 kg/m(2), respectively. Pre-dialysis ECW/TBW was significantly correlated with only pulse pressure (r = 0.5, P = 0.003) whereas post-dialysis ECW/TBW had significant correlations with pulse pressure, systolic blood pressure, and diastolic blood pressure (r = 0.6, P = 0.001, r = 0.4, P = 0.04, r = -0.4, and P = 0.02, respectively). After dialysis, the mean values of ECW/TBW, systolic blood pressure, mean arterial pressure, and pulse pressure were significantly decreased. ECW/TBW was used to classify the patients into normohydration (≤ 0.4) and overhydration (>0.4) groups. Systolic blood pressure, mean arterial pressure, and pulse pressure significantly reduced after dialysis in the normohydration group but did not significantly change in the overhydration group. Pre-dialysis pulse pressure, post-dialysis pulse pressure, and post-dialysis systolic blood pressure in the overhydration group were significantly higher than normohydration group. Due to the simplicity and cost, blood pressure parameters, especially pulse pressure, might be a simple reference for clinicians to determine hydration status in HEMO patients.
透析间期体重增加和液体清除不充分导致的慢性容量超负荷在高血压控制不佳中起重要作用。虽然生物电阻抗已被引入作为评估水合状态的准确方法，但该仪器在一般血液透析（HEMO）中心并不普及。本研究旨在探讨生物电阻抗测量的水合状态与慢性HEMO患者血压参数之间的相关性。采用多频生物电阻抗分析来确定32例稳定HEMO患者透析前和透析后的水合状态。通过生物电阻抗分析各节段总和确定的细胞外液/总体液（ECW/TBW）用作水合状态指标。平均年龄为57.9±16.4岁。平均干体重和体重指数分别为57.7±14.5kg和22.3±4.7kg/m²。透析前ECW/TBW仅与脉压显著相关（r = 0.5，P = 0.003），而透析后ECW/TBW与脉压、收缩压和舒张压均显著相关（r分别为0.6，P = 0.001；r = 0.4，P = 0.04；r = -0.4，P = 0.02）。透析后，ECW/TBW、收缩压、平均动脉压和脉压的平均值显著降低。ECW/TBW用于将患者分为正常水合（≤0.4）和水合过度（>0.4）组。正常水合组透析后收缩压、平均动脉压和脉压显著降低，而水合过度组无显著变化。水合过度组透析前脉压、透析后脉压和透析后收缩压显著高于正常水合组。由于血压参数简单且成本低，尤其是脉压，可能是临床医生确定HEMO患者水合状态的简单参考指标。
