台灣長年以來都有「洗腎王國」的惡名，光是2018年給付慢性腎臟病就高達513億，占健保總額將近7％。而在2019年的台灣腎病年報指出，2013-2017年透析盛行數呈逐年增加之趨勢，因此，血液透析在醫療上已經成為不可忽視的課題。透析患者在接受透析治療前需接受植入透析廔管的手術，透析廔管分為兩種，通常較常使用動靜脈廔管，將動脈與靜脈連接起來待血管成熟後刺穿。在洗腎結束後，穿刺針孔必須使用止血帶適當加壓10-15分鐘至止血後，更換敷料。為避免止血不適當造成血液流失及危險，必須注意止血所需的壓力與方法。而目前醫院的護理人員仍然使用傳統止血帶方式與自身經驗來進行止血，此方法雖然快速方便但也伴隨著非常多危險性，因為每位患者的血壓與其他生理條件不盡相同。而廔管對於洗腎病患有「生命線」之稱，不適當的壓力可能造成廔管損壞或無法有效止血。
本項研究目的為建立一套用於血液透析的適應性充氣止血帶系統，這項系統包含一套藍芽血壓計與藍芽止血帶。前者使用微控制器控制血壓模組執行量測血壓資訊，並將數據透過藍芽傳送到藍芽止血帶，數據將會在藍芽止血帶中預先寫好的回歸模型下去計算最合適的止血帶壓力，並同樣使用微控制器與控制單元對止血壓脈帶進行充氣與平衡壓力，並在用戶定義的時間結束後放壓並停止。
回歸分析實驗的部分，我們使用Terason t3000超音波都卜勒系統與壓力計收集了一些健康人的血壓資訊。實驗首先對受測者進行止血帶加壓(每次施加10mmHg)直到都卜勒超音波量測到的血流速歸零為止，並記錄與分析血流速的變化與其他資訊來建立一套回歸模型。由於此套系統是應用於洗腎病患，有別於一般手術病患的止血壓力，這套系統使用的血流量回歸模型並不會將血流完全止住，而是讓些微的血流能夠正常通過。我們將這套回歸模型定義為最佳止血壓力(OTP)。最終，我們會使用這套系統實驗最佳止血壓力的成效並評估結果。

Taiwan has long been notorious as the "Kingdom of Kidney Dialysis". It paid 51.3 billion for chronic kidney disease, accounting for nearly 7% of the total health insurance in 2018. In the 2019 Annual Report on Kidney Diseases in Taiwan, it was pointed out that the prevalence of dialysis in 2013-2017 was increasing year by year. Therefore, hemodialysis has become a medical issue that cannot be ignored. Dialysis patients need to undergo surgery to implant a dialysis fistula before receiving dialysis treatment. Dialysis fistula is divided into two types. An arteriovenous fistula is usually used to connect arteries and veins and then puncture after the blood vessels mature. After dialysis, the puncture hole must be appropriately pressurized with a tourniquet for 10-15 minutes to stop bleeding, and then the dressing should be changed. In order to avoid blood loss and danger caused by improper hemostasis, attention must be paid to the pressure and methods required for hemostasis. At present, the nursing staff in the hospital still use the traditional tourniquet method and their own experience to stop bleeding. Although this method is quick and convenient, it is also accompanied by many dangers because each patient's blood pressure is different from other physiological conditions. For people with dialysis, the fistula is known as the "lifeline". Improper pressure may damage the fistula or fail to stop bleeding effectively.
The purpose of this research is to establish an adaptive pneumatic tourniquet system for hemodialysis. This system includes a Bluetooth sphygmomanometer and a Bluetooth tourniquet. The former uses a microcontroller to control the blood pressure module to perform the measurement. The blood pressure information will send to the Bluetooth tourniquet through Bluetooth. The data will be calculated in the regression model pre-written in the Bluetooth tourniquet to calculate the most suitable tourniquet pressure. The microcontroller and control unit will also be used to inflate the tourniquet cuff, balance the pressure, and then release the pressure to the end of the system after the user-defined time is up.
For the regression analysis experiment, we used Terason t3000 ultrasonic Doppler system and pressure gauge to collect blood pressure information of some healthy people. The experiment first pressurizes the subject with a tourniquet (increase 10mmHg each time) until the blood flow velocity measured by Doppler ultrasound returns to zero and records and analyzes the changes in blood flow velocity and other information to establish a regression model. Since this system is applied to dialysis patients, it is different from the hemostatic pressure of general surgical patients. The blood flow velocity regression model used in this system does not entirely stop the blood flow but usually allows the slight blood flow to pass. We define this regression model as the optimal tourniquet pressure (OTP). In the end, we will use this system to test the effectiveness of the optimal tourniquet pressure and evaluate the results.

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