Fundamental Study on Measurement and Analysis of Biometric Data
from Abdomen and Lumbar Region for Prediction of Bowel Movement
No.2281272

Amane Hasegawa(Supervised by Prof. Masaki Kyoso)
ABSTRACT
Among those certified as requiring nursing care in Japan, there are currently approximately 3.61
million people requiring nursing care 2 or higher who need assistance with toileting, and this number
is expected to continue to increase. In a previous survey conducted by the Cabinet Office, the mostdifficult task was excretion care. If caregivers can directly know the timing of bowel movements, it
is expected that the burden of excretion care will be greatly reduced. Currently, there are previous
studies on the prediction of defecation, but they are limited to identifying the conditions before andafter defecation, and none has yet been established as a defecation prediction method. The ultimate
goal of this study is to construct a system to noninvasively detect bowel movements in daily life byusing an unprecedented abdominal measurement method, the impedance method. As a first step, weinvestigated the conditions for measuring abdominal impedance, investigated the stability ofimpedance measurement and the effects of changes in contents, and measured and analyzed
abdominal impedance to understand the intestinal contents. To examine the impedance measurement
conditions, we used an ultrasound system to observe the location of the intestines from the bodysurface and the appearance of the abdomen while eating and drinking. As a result, it was found that
there were individual differences in bowel position and that gas was generated in the stomach andintestines during eating and drinking, making it difficult to perform ultrasonic measurements. In theinvestigation of the stability of impedance measurement and the effects of content changes, thestability of absolute impedance values was confirmed in the forearm, where the tissue is more
uniform than in the abdomen, by conducting multiple comparison experiments on different days,
with the same subject and different subjects. In addition, gastric impedance measurement, which iseasier to capture changes in contents than the intestine, showed that impedance increased whendrinking water, and that changes in contents were reflected in impedance. In the abdominal
impedance measurement before and after eating and drinking, which was conducted for abdominal
impedance measurement and analysis to understand the intestines, two subjects were compared
under the same subject conditions such as before and after eating and drinking, and the r esults
showed different frequency characteristics. In the impedance measurement before and afterdefecation, it was found that the frequency characteristics of the impedance differed greatly
depending on the measurement date, even in the same subject. Therefore, it is necessary to collectdata from more subjects at different times and in different states, and to analyze a large amount ofdata in order to develop a bowel situation estimation model for predicting voiding using predictor
variables such as gender, age, and abdominal circumference. It is believed that a bowel situation
estimation model can be developed using predictive variables such as gender and age.