A study on the fluid mechanical urinary bladder simulator and reproduction of human urodynamics

Abstract

Many aging people and patients have difficulties in bladder control. Its symptoms are largely urinary frequency and urinary incontinence, which can cause life-threatening illnesses. A therapeutic research for bladder nerves and surgical treatment has been studied. However, such treatments are likely to cause complications and need more reliability and safety. An urodynamic study, which is designed to monitor the relationship between flow, pressure, and volume by inserting a condom catheter into the urethra, is most commonly used for the measurement of bladder operation. Unfortunately, this method may cause inconvenience and side effects. Thus, a urinary tract-bladder-resembling experimental device was manufactured and used for the study based on experimental data. Similar research to human urinary tract-bladder dynamics is lacking. Therefore, this study intended to design mechanical urinary-bladder simulator, which resembled the urinary tract system including the bladder, ureter, and urethra. The fluid mechanical urinary tract-bladder simulator was manufactured by using a pump, hose, flow-meter, pressure sensor, rubber membrane, syringe and control software. In addition, the unique pressure-volume relationship in the bladder and urination affected by abdominal pressure could be comprehended with the use of the manufactured simulator. In this simulator, bladder pressure change and urination control were reproduced by the pump and valve by letting water flow in, while non-linear increase and reduction of pressure was reproduced by application of abdominal pressure on the elastic rubber membrane and plastic hemispherical capsule-connected syringe. The abdominal pressure added in the system can expect to reproduce other types of urinary symptoms. As a result, the fluid mechanical simulator made it possible to reproduce human urinary tract bladder urodynamics movement. This simulator will be effectively used for reliability and stability of the research for the improvement of bladder management that is currently lacking reliability and stability. It can also be utilized for the future application. The fluid mechanical simulator can be useful method to avoid other difficulties which are unpredictable conditions of the human body or seeking the approval of the IRB(Institutional review board) for bioethics. Additionally, an invasive bladder monitoring system that utilizes the simulator has been developing that will benefit patients.