微控制器在適化透析之應用

Application of Microcontroller on Optimal Dialysis

顏士翔(Shi-Xiang Yan)

指導教授 ： 張炎林

中原大學/工學院/醫學工程研究所/碩士(2003年)

https://doi.org/10.6840/cycu200300738

摘要

對於一些長期接受血液透析的患者而言，透析期間出現的不平衡症候群一直是他們最困擾的問題，嚴重的會威脅到他們的生活品質與生命安全。所謂不平衡症候群，是指因透析治療所引起的噁心、嘔吐、頭痛、頭暈、肌肉痙攣、低血壓與高血壓等併發症，目前學理上大多認為是由於透析期間細胞外液溶質濃度下降太快，使細胞外液與內液間的濃度差相差太大所致。
近年來，Lee與Chang採用準確性較高的雙室模式(Two-Pool Model)，提出適化透析(optimal dialysis)的新構想，透過分階段控制血液流量或透析液流量，使得透析病患可保持在較低的細胞內外液濃度差情況下進行透析治療，並已得到初步的臨床證實。本研究室一直致力於適化透析系統的開發，一套完整的血液透析治療處方軟體已於理論與臨床模擬上證實其實用性，以及血液透析機中央監視/控制系統初型都已由本研究室開發完成。
本研究是改良學長血液透析中心中央監視／控制系統的設計。以微控制器替代現行電腦控制洗腎機的功能。將病人的生理參數輸入由本研究室開發之適化透析軟體的電腦， 經軟體模擬後，計算出病人理想之血液流量或透析液流量，微控制器接收電腦端透過Print port輸出的訊號，並寫入儲存卡上之EEPEOM，儲存完後，離線，將卡片插入控制模組，微控制器將卡片內控制訊號輸出，經DAC轉換，控制洗腎機透析幫浦；此時輸出之電壓經12bit ADS7842E類比轉數位IC轉換為數位訊號，由微控制器與原數位訊號作比較，若誤差過大，則進行補償，達到適化透析的目標。
本系統儲存模組與控制模組之電路、韌體皆已完成，經測試後，血液流量輸出誤差在-7.4 ml/min內，符合洗腎機在調控一次誤差量在±10 ml/min內。

關鍵字

微控制器 ； 適化透析

並列摘要

For the patients receiving long-term hemodialysis treatment, the disequilibrium syndromes during the dialysis process, that might eventually imperil their lives, and always been the most disturbing problem. The so-called disequilibrium syndrome refers to the epiphenomenoms during the dialysis treatment, including nausea, vomiting, headache, dizziness, convulsion, hypotension or hypertension. Theoretically, the reasons for such complication can be attributed to the prompt decrease in density of extracellular fluid that solutes during dialysis, while is far below the density of intercellular fluids.
In recent years, Doc. Lee and Doc. Chang have employed a method of higher accuracy Two-Pool Model, and introduced a new concept of optimal dialysis. By controlling blood flow rate or dialysate flow rate step by step, patients receive the dialysis treatment while the density between extracellular and intercellular fluids is maintained at a lower level. This method has been obtained by preliminary clinical evidence, and our research center has been committed to the development of optimal dialysis systems. A complete set of software for blood dialysis treatment have been tested and proven effective both on theoretical and clinical simulations, and the primal prototype of dialysis machine central monitor/control system have also been optimized by our research center.
This research upgrade the original design of blood dialysis center's central monitor/control system. It replaces computer with Micro- controller for playing a role to control dialysis machine. In the beginning, inputting the patient’s physiological parameters to the software of dialysis treatment, which is designed by our laboratory. After simulating of software, it shows the patient’s ideal blood flux or dialysate flux, and the microcontroller accepts computer’s signals (outputted by print port) and writes it to EEPEOM on the storage-card. After storing, then disconnecting and inserting storage-card into controlling-module. Microcontroller will outputs signals and transforms into voltage by DAC. After digital/analog converting, control dialysis machine pumps; at this time, 12 bits DAC (ADS7842E) converts output signal voltage to digital signal. In comparison with digital signal to the original digital, while the error is huge and can’t be ignored, then proceed to compensate for error until satisfying the object of optimal dialysis.
The circuit and firmware on the storing-module and controlling-module has been finished. After test, the error on output of blood-flux is less than –7.4 ml/min. The error is acceptable on dialysis machine, which is need to be less ±10 ml/min in an adjustment.

並列關鍵字

Optimal dialysis ； Microcontroller

參考文獻

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