Abbey J C, Close L
J Microw Power. 1983 Sep;18(3):305-9. doi: 10.1080/16070658.1983.11689335.
A tetrapolar 75-kHz, 0.2-mA constant-current electrical impedance measuring system was used to monitor urinary volume change over 12 four-hour sessions in 20 male and 20 female normal human subjects. Two spot voltage electrodes (E) and two spot current electrodes (I) were applied 5 cm above the symphysis pubis at 15 cm interelectrode distances, 7.5 cm bilaterally from the midline. Five measurements of impedance and skin temperature were made at 15-minute intervals over 4 hours. Specific gravity, impedance change, and volume were recorded with each voided specimen. Suprailiac and infrascapular skinfolds, and circumference at iliac crests were measured. The subjects drank 175 ml of fluids per hour during the testing session. Subjects remained in the supine position during measurements. They walked to the lavatory to void. Bladder fullness is defined as the urge to void. Results include: (1) a poor negative correlation between specific gravity of urine and impedance (r2 = 0.1240, p less than or equal to 0.01); (2) baseline impedance was dependent upon individual subject characteristics: in males skin area, skinfold thickness, and suprailiac circumference; in females skinfold thicknesses and time since last menstrual period; (3) impedance decreased with urinary bladder filling and increased upon voiding (p less than or equal to 10(-10)); (4) the cumulative sum test (CUSUM) predicted time to void in 78.9% of voids (p less than or equal to 0.05) and no void (when voiding did not occur) in 66.8% of no voids (p less than or equal to 0.05). Overall accuracy of the CUSUM test was 74.6% (p less than or equal to 0.05).
采用一种四极75千赫、0.2毫安恒流电阻抗测量系统，对20名男性和20名女性正常受试者进行了12次为时4小时的尿液量变化监测。在耻骨联合上方5厘米处、电极间距15厘米、距中线两侧各7.5厘米处，施加两个点状电压电极（E）和两个点状电流电极（I）。在4小时内，每隔15分钟进行5次阻抗和皮肤温度测量。每次排尿标本均记录比重、阻抗变化和尿量。测量了髂上和肩胛下皮肤褶厚度以及髂嵴周长。测试期间受试者每小时饮用175毫升液体。测量时受试者保持仰卧位。他们走到厕所排尿。膀胱充盈定义为有排尿冲动。结果包括：（1）尿比重与阻抗之间呈弱负相关（r2 = 0.1240，p≤0.01）；（2）基线阻抗取决于个体受试者特征：男性为皮肤面积、皮肤褶厚度和髂上周长；女性为皮肤褶厚度和上次月经后的时间；（3）阻抗随膀胱充盈而降低，排尿时增加（p≤10-10）；（4）累积和检验（CUSUM）在78.9%的排尿情况中预测了排尿时间（p≤0.05），在66.8%的无排尿情况（即未发生排尿时）中预测了无排尿（p≤0.05）。CUSUM检验的总体准确率为74.6%（p≤0.05）。
