實現可攜式低壓連續血壓參數量測裝置

Realization of a portable low-pressure continuous blood pressure measurement device

蘇琬稜(Wan-Leng Su)

指導教授 ： 徐良育

中原大學/工學院/生物醫學工程研究所/碩士(2011年)

https://doi.org/10.6840/CYCU.2011.00061

摘要

侵入性血壓量測在臨床上可供最精確的連續血壓訊號紀錄，雖然精準，但易感染，且在一般檢查及觀察的項目下，並不適宜。因此市面上不斷的開發各種非侵入式的血壓測量儀器，供給一般民眾用於簡單檢查以及居家照護，但大部分的儀器卻僅能提供某一個時間點的收縮壓與舒張壓及平均血壓三個特徵值，無法全面呈現血壓訊號的整體資訊。
因此，本研究改良連續血壓量測系統，並使之微小化。整體架構包含了：血壓校正量測系統、恆定壓力控制迴路及周邊顯示裝置。本系統主要是以C8051F320控制晶片來進行即時特徵值偵測以及訊號處理，調控恆定壓力使氣囊壓力維持在39～41 mmHg之間，以達到長時間、即時記錄連續血壓之目的。
系統實現後，本研究針對六位正常、無心血管疾病之年輕受測者，進行Valsalva Maneuver憋氣實驗，以改變受測者的血壓。同時利用本研究所實現的非侵入連續血壓量測裝置對左手進行連續血壓紀錄並利用床邊監視器（Spacelab 9036）在受測者右手分四個時段進行對照組的測量。實驗結果分憋氣前、後，利用本系統即時處理之結果與Matlab離線處理結果進行比對。。
系統測試結果顯示，本系統所量測到的連續血壓所呈現的的即時變化，符合憋氣後，脈壓(PP)振幅降低的生理現象；但與對照血壓值比較的部份，則由於測量時間是在憋氣結束後，因此所測得的PP值，並沒有明顯的降低。經由t-test統計比較本系統與Matlab測得之tau值，結果顯示兩者有明顯的差異(P<0.05)，其原因是因為Matlab程式是以浮點數計算，因此造成些微的誤差，日後需再以修正。本研究結果證明，本系統可以動態的追蹤受測者血壓的變化，在需要即時血壓資訊的環境下，此裝置可以達到預期的目的。

關鍵字

動脈血管順應性 ； 低壓連續血壓

並列摘要

In clinical application, invasive blood measurement can provide accurate blood pressure signal. However, it is not safe. And it is not suitable for routine inspection. Therefore, many non-invasive blood pressure measurement devices in the market provide users with simple method for home care. But, most of them can only provide diastolic, systolic and mean blood pressure reading, without other detail blood pressure information.
For this reason, in this study, improvements were made on the existing continuous blood pressure measurement system to make it smaller and portable. The system hardware includes blood pressure calibration, constant pressure control, and peripheral display devices. The proposed system uses micro-controller, C8051F320, to process signal and to calculate parameters in real time. It controls pump voltage in order to maintain the cuff pressure around 39 to 41 mmHg. Thus, it is possible to record continuous blood pressure signals in a long-term situation.
In this study, six normal, healthy volunteers who have no heart diseases were recruited to perform Valsalva maneuver in order to change their blood pressure. At the same time, the continuous blood pressure signal were recorded from the left hand while the conventional blood pressure reading were obtained from subjects’ right hand using a bedside monitor (model 9036, Spacelab, USA). In the result analysis, comparisons were made between the real-time results from the proposed system and results computed by Matlab at three time periods including: before, during and after breath holding. Four control measurements were obtained from volunteers’ right hand using the Spacelab monitor.
The results demonstrate that the real-time variation of the continuous blood pressure waveform obtained using the proposed system match the same physiology phenomena that PP decrease after breath holding. However, when compared with control blood pressure, there is no significant decrease in PP value. This may due to the fact that the time of measurement is after the end of breath holding. Comparing the tau values between the proposed system and Matlab, there is significant different (P<0.05). The reason of this different may be caused by the fact that the Matlab program uses floating point computation. The outcome proves that the device can trace the dynamic changes of user’s blood pressure. The device will achieve the expected purpose in a environment that requires real-time information of blood pressure.

並列關鍵字

arterial compliance. ； low-pressure continuous blood pressure

參考文獻

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