Development Of Continuous Hemodynamic Monitoring System

Hemodynamic monitoring is one of the most important monitoring contents for clinical anesthesia and ICU. It is the indispensable method for critically ill patients with cardiac functional changes and other seriously-ill patients. In the process of diagnosis and treatment for critically ill patients, continuous hemodynamic monitoring can dynamically provide the most basic, timely and objective pathological evidences, guiding the clinical practice, significantly improving the level of clinical treatment. Development and application of continuous hemodynamic monitoring technology has been fully acknowledged by medical staffs both at home and abroad.Depending on the development situation and current situation of products at home and abroad, by compared the merits and demerits in each monitoring method, this paper presented the cardiac output monitoring module which based on thermodilution and continuous thermodilution, and integrated with the two channels monitoring module of invasive blood pressure to become a system of continuous hemodynamic monitoring. The main applications, significance and importance had been described in this paper at first, introduced the current situation and mainstream products at home and abroad, expounded the principle of various hemodynamic monitoring techniques and analyzed the advantages and disadvantages of each technique. Then the design scheme of continuous hemodynamic monitoring system is proposed, and detailed analysis and development of every aspects which includes the system architecture, hardware design, the underlying driver software system design, the PC monitoring software design, application safety design, algorithm analysis method, parameter calculating and etc had been made. Finally, successfully developed a continuous hemodynamic monitor prototype. The design of the system’s hardware and software were used the modular design method and then achieved reintegration, the development of system could be divided into four aspects: first, the hardware system, host processor which utilized the 32-bit ARM microprocessors of STM32 series, ADC with 24-bit high-precision, hardware system which includes the designs of power supply module, sensor driver module, signal acquisition module, safety control module and etc; secondly, the PC monitoring system software, which was designed by using the VS2008 MFC, mainly contains data communications, monitoring information display, data file operations, the interaction between upper and lower computer and etc; thirdly, the underlying software system design includes system self-test, the peripheral circuit control, signal acquisition, data preprocessing, communication, various command response and so on; finally, the algorithm part,which comprises the calculating and optimizing method of parameters directly measured, optimization approach, and the calculation of hemodynamic parameters and oxygenation parameters.The evaluation of continuous hemodynamics monitoring system is based on relevant national industrial standards and related testing schemes had been made depend on experiment conditions. The assessment is from the following two aspects: basic performance test and clinical verification, and evaluated the combination property of system. The test data and clinical verification showed that this system had advantages of high measurement accuracy, good system stability, strong usability, and so on. All these work had laid solid foundation for enhancing the system in later stage and made it more closer to achieve the domestication of the monitoring device of continuous hemodynamics.