血壓數值能夠反映人體心臟與血管的相關疾病，可以做為評估心血管狀況的參考指標。目前血壓量測方法如聽診法或是電子血壓計的振盪法，皆會用到壓脈帶對手臂充放氣，如此會讓使用者感到不舒服且無法作連續的血壓量測，所以本論文希望以脈波到達時間(pulse arrival time，PAT)做為血壓量測的方法，自行開發一套血壓量測裝置。
此裝置使用的MAX86150生物感測器，可以同時量測心電圖 (ECG)和光體積變化描述波形 (PPG)。本論文開發了ECG的R波和PPG波峰偵測演算法去計算PAT。在10個人的實驗中，每個人量測運動前2次的血壓和運動後2次的血壓。結果發現，利用聽診法量測到的收縮壓數值和PAT的相關性平均為0.76，顯示只有使用PAT參數去推估血壓，可能無法得到準確的血壓數值。
此外，在本論文也探討使用手指PPG訊號與壓脈帶充放氣的關係，當壓脈帶內部的壓力大於收縮壓時，手指上的PPG訊號就會消失；而壓脈帶放氣時，手指的PPG訊號會逐漸出現，因此藉由PPG訊號來判斷收縮壓的壓力值為何，再與聽診法得到的收縮壓比對後，其平均誤差與標準差為0.18±12.62毫米汞柱。雖然此結果未能達到AAMI標準的5±8毫米汞柱，但是未來可以再繼續利用本裝置去改良更準確的演算法。

Blood pressure (BP) is one of fundamental reference parameters in cardiovascular assessment, and is highly related to heart diseases and artery diseases. For now, BP measuring method such as auscultatory or oscillometric method will use cuff to pressurized human arm, this will make user uncomfortable and cannot measure BP continuously. In this thesis, we develop a BP measuring device through pulse arrival time (PAT).
The device is using MAX86150 biosensor to measure Electrocardiogram (ECG) and Photoplethysmography (PPG) simultaneously. In this thesis, We develop a algorithm of ECG R wave and PPG peak detection to calculate PAT. The experiment with 10 subjects, each subject will measure BP twice before and after running. The result shows that the average correlation coefficient between PAT and systolic BP (SBP) measured by auscultatory method is equal to 0.76, it means that only a parameter of PAT to estimate BP may not get the accuracy value.
Besides, in this thesis , there is a discussion about the relationship of finger’s PPG signal and cuff’s inflation and deflation. Using PPG signal to decide SBP through PPG signal will diappear during cuff’s inflation and it will reappear during cuff’s deflation. The proposed method compared with the SBP value measured by auscultatory method, has a result of 0.18±12.62 mmHg, cannot fit in AAMI standard. Thus, we will keep using selfmade device to imporve a more accuracy algorithm.

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