生物电阻抗系统的电极位置对膀胱尿量测量的影响

Effect of electrode location on bladder volume measurement in bioimpedance system

目的研究生物电阻抗测量系统中电极位置对膀胱尿量信号特征的影响,提高检测过程中信号的敏感度,以帮助尿潴留患者定时排尿。方法健康男性大学生8名,采用双路开关同时采集两路电极位置的信号,分别观察电极在小腹部不同位置及测量电极和刺激电极的相对距离对阻抗变化值△Z和阻抗变化率△Z/Z的影响。结果在使用生物电阻抗技术测量膀胱积尿过程中,生物电阻抗Z呈现变小的趋势,不同的刺激/测量电极位置对应的阻抗变化值△Z和变化率△Z/Z不同。结论肚脐下10cm,正负两个测量电极距肚脐中线均为3 cm的位置,正负两个刺激电极与对应正负两个测量电极间距离均为5 cm的位置为最佳的测量位置,其阻抗变化值△Z达(1.2±0.6)Ω,变化率△Z/Z达8.2%±4.9%。该位置的确定对使用生物电阻抗技术提醒尿潴留患者在恰当的时间排空膀胱具有重要的临床意义。

This paper investigates the effect of electrode position on bladder volume measurement with bioimpedance system which is helpful for the patients with urine retention to micturate. Methods The variation of bioimpedance ΔZ and gradient of bioimpedance ΔZ/Z in eight healthy male students are observed in bladder filling,when the stimulating or measuring electrodes are fixed different positions in abdomen by using a two-way switch.Results During the measurement of bladder filling,there is a decrease trend for bioimpedance Z.The variation and gradient of bioimpedance are different with the different electrode positions.Conclusions The optimal location is:1 0 cm under navel,the measuring electrodes both are 3 cm to navel’s midcourt line,and the distance between stimulating and measuring electrodes both are 5 cm.In this electrode location,the variation (ΔZ ) of bioimpedance is up to (1.2 ±0.6 ) ohm,and the gradient of <br> bioimpedance (ΔZ/Z ) is up to 8.2% ±4.9%.The location is important in clinic for warning the patients to micturate in time.