本研究旨在藉由低度壓力的量測方式實現連續血壓系統，並且針對先前之系統進行硬體的改良以及軟體功能建構，本文亦提出改進連續血壓轉換公式以達到較穩定的血壓動態變化。 測量連續血壓變化的時候，在上臂或手腕包覆壓脈袋，並將空氣灌進壓脈袋，以低度壓力(30~60mmHg)壓迫上臂的血管，受壓迫的血管中血流壓力回傳至壓脈袋與壓力感測器，壓力感測器的輸出信號傳送到兩個類比輸入通道，再透過個人電腦進行血壓參數的計算，並且即時顯示經低壓轉換所得之血壓值及心跳頻率。本系統的人機介面是由虛擬儀控程式LabVIEW所設計，並經由NI-DAQ USB-6009資料擷取卡，做數位輸出以及類比輸入的工作。 為確認本系統的準確性，本研究分別採用血壓計與心率變異儀的量測數值與連續血壓量測的結果比較。經過實際測試的數據分析，本系統所使用低度壓力量測方式與市面上的血壓計結果吻合。此外，本文利用梅爾波（Mayer waves）來觀察長時間血壓變化，而連續血壓系統量測到的低頻血壓頻譜與心率變異儀所量測的低頻的血壓變異一致，因此本研究驗證了連續血壓方法的準確性與穩定性。 本研究改進低壓連續量測系統的血壓動態追蹤功能，並且提高了系統的穩定性與精準度，實驗結果證實低壓量測方法符合非侵入式自動血壓計型式認證技術規範。 The main purpose of the research is to design a continuous blood pressure (BP) measurement system based on low pressure approach. In this study, we modify the low pressure translating formula of continuous blood pressure and improve the hardware of system to achieve the more accurate tracking capability of dynamic blood pressure. The measurement of continuous blood pressure is achieved by applying cuff on the arm or wrist of subjects. The cuff is filled with air and maintained in low pressure (30~60mmHg). The signals of cuff pressure and pulse vibration are at the output of the pressure sensor. A filtering and amplifying circuit is introduced to separate the two signals into two analog input channels of Data Acquisition Card. Thus, blood pressure and heart rate can be calculated after acquiring the data by the personal computer. The interface of the system is completed by LabVIEW. The digital output and the analog input signals are operated by utilizing National Instruments Data Acquisition Multifunction I/O Card. Moreover, Mayer waves at subjects’ wrist artery for evaluating the blood pressure variation (BPV) in low frequency is recorded. The estimated BPV is verified with the commercial heart rate variation (HRV) equipment. According to the experimental results, it proves that the accuracy and stability of the continuous blood pressure measurement systems. In this thesis, a modified dynamic blood pressure (BP) measurement system is proposed. By the experimental results, it is shown that the accuracy and the stability of proposed system could meet the requirement of Non-Invasive Automated Sphygmomanometers standard (AAMI SP10).
