因為高血壓疾病對於人體後續造成的危害，以及其不易被發現的特性，連續偵測血壓對現代人的疾病預防和診斷具有重要的臨床價值。然而，傳統的血壓測量儀器由於其舒適度差、攜帶性差且無法進行連續偵測的問題，研發出一種可連續偵測且改善傳統血壓計問題的設備是必要的，因此本文提出了一個基於FBG的連續血壓量測系統。
本研究利用雙FBG的低成本架構，透過量測光功率的改變，而取得人體的脈搏波形。將波形中的脈波傳遞時間(PTT)數據提取出，透過PTT對袖帶式電子血壓計所量測到的參考血壓做擬合，得出估算血壓的模型，此估計模型是利用19名受試者的數據去建立的，並且透過兩名高血壓受試者的數據對血壓估計模型進行調整，另外還對8位受試者進行臨床實驗，其中包含一位高血壓患者，以測試本實驗架構的準確度，最後再分別加入Pt和Dt兩個參數進行微調，進一步降低擬合結果的誤差。結果顯示，與袖帶式電子血壓計相比，量測的收縮壓(SBP)及舒張壓(DBP)其最終誤差分別為2.20mmHg和2.10mmHg，這樣的誤差在我國經濟部標準檢驗局所規定之無創血壓測量設備的臨床實驗規範誤差內，表明本實驗架構具有良好的準確性。

The continuous monitoring of blood pressure is of significant clinical value for disease prevention and diagnosis, considering the potential damage, such as cardiovascular diseases, caused by hypertension and its often undetectable nature. However, traditional blood pressure measurement devices suffer from discomfort, poor portability, and the inability to provide continuous monitoring. Therefore, this study proposes a continuous blood pressure measurement system based on Fiber Bragg Grating (FBG) technology.

In this research, a low-cost dual-FBG architecture is employed to capture the pulse waveform of the human body by measuring changes in optical power. The Pulse Transit Time (PTT) , ejection time and diastolic time, extracted from the waveform are used in a blood pressure estimation model by fitting it to the reference blood pressure obtained from an electronic sphygmomanometer. The estimation model is developed using data from 19 subjects, with adjustments made using data from two hypertensive patients. Clinical experiments were conducted on eight subjects, including one with hypertension, to assess the accuracy of the proposed framework.

The results demonstrate that compared to the electronic sphygmomanometer, the measured Systolic Blood Pressure (SBP) and Diastolic Blood Pressure (DBP) exhibit errors of 2.20 mmHg and 2.10 mmHg, respectively. These errors fall within the clinical experiment specifications for non-invasive blood pressure measurement devices, as prescribed by the Bureau of Standards, Metrology, and Inspection of the Ministry of Economic Affairs in our country, indicating the high accuracy of the proposed framework.

[1] Vasan RS, Larson MG, Leip EP, et al., “Impact of high-normal blood pressure on the risk of cardiovascular disease,” The New England Journal of Medicine, vol. 345, no. 18, pp. 1291-1297, Nov. 2001.

[2] Kannel WB, "Blood pressure as a cardiovascular risk factor: prevention and treatment." JAMA, vol. 275, no. 20, pp. 1571-1576, May 1996.

[3] Pickering TG, White WB, American Society of Hypertension Writing Group, "When and how to use self (home) and ambulatory blood pressure monitoring." J Am Soc Hypertens, vol. 2, no. 3, pp. 119-124, May-Jun 2008.

[4] Ohkubo T, Imai Y, Tsuji I, et al., "Prediction of stroke by ambulatory blood pressure monitoring versus screening blood pressure measurements in a general population: the Ohasama study." J Hypertens, vol. 18, no. 7, pp. 847-854, Jul 2000.

[5] Ohkubo T, Asayama K, Imai Y, "The value of self-measured home blood pressure in predicting stroke." Expert Rev Neurother, vol. 6, no. 2, pp. 163-173, Feb 2006.

[6] Lee SS, Kim CS, Jeong YS, et al., "Measurement of blood pressure using an arterial pulsimeter equipped with a Hall device." Sensors, vol. 11, no. 2, pp. 1784-1793, Feb 2011.

[7] Fierro G, Silveira F, Armentano R, "Central blood pressure monitoring method oriented to wearable devices." Health Technol, vol. 6, no. 3, pp. 197-204, Sep 2016.

[8] Sharath U, Anitha H, Mithun N, et al., "Blood pressure evaluation using sphygmomanometry assisted by arterial pulse waveform detection by fiber Bragg grating pulse device." J Biomed Opt, vol. 18, no. 6, pp. 067010-067010, Jun 2013.

[9] Jia D, Liang J, Zhang X, et al., "A fiber Bragg grating sensor for radial artery pulse waveform measurement." IEEE Trans Biomed Eng, vol. 65, no. 4, pp. 839-846, Apr 2018.

[10] Lee SS, Kim CS, Kim HC, et al., "Estimated blood pressure algorithm for a wrist-wearable pulsimeter using Hall device." J Korean Phys Soc, vol. 58, pp. 349-352, Jan 2011.

[11] Miyauchi Y, Koyama S, Ishizawa H, "Basic experiment of blood-pressure measurement which uses FBG sensors." In: 2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC). IEEE, 2013.

[12] Li L, Wei J, Zhou L, et al., "Continuous and accurate blood pressure monitoring based on wearable optical fiber wristband." IEEE Sensors J, vol. 21, no. 3, pp. 3049-3057, Feb 2021.

[13] Kreuzer M, "Strain measurement with fiber Bragg grating sensors." HBM, Darmstadt, S2338-1.0 e 12 , 2006.
[14] 孙杉杉, 张建忠, 蔡恒达, "小型化光纤光栅解调系统设计及寻峰算法的模拟评测." 应用光学学报, vol. 41, no. 3, pp. 618-625, Mar 2021.

[15] 王立康, "寬頻摻鉺光纖放大器之基本原理." 科儀新知, vol. 151, pp. 30-38, 2006.

[16] 林育德. "脈波信號與PPG信號特徵之相關性研究." 中醫藥年報, 2013.

[17] Peter L, Noury N, Cerny M, "A review of methods for non-invasive and continuous blood pressure monitoring: Pulse transit time method is promising?." IRBM, vol. 35, no. 5, pp. 271-282, Oct 2014.

[18] Kao YH, Huang YC, Lo HC, et al., "Optimizing a new cuffless blood pressure sensor via a solid–fluid-electric finite element model with consideration of varied mis-positionings." Microsyst Technol, vol. 22, pp. 1437-1447, May 2016.

[19] Peter L, Noury N, Cerny M, "A review of methods for non-invasive and continuous blood pressure monitoring: Pulse transit time method is promising?." IRBM, vol. 35, no. 5, pp. 271-282, Oct 2014.

[20] Shriram R, Sivaprakasam M, Bhargava K, et al., "Continuous cuffless blood pressure monitoring based on PTT." In: 2010 International Conference on Bioinformatics and Biomedical Technology. IEEE, 2010.

[21] Teng XF, Zhang YT, "An evaluation of a PTT-based method for noninvasive and cuffless estimation of arterial blood pressure." In: 2006 International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE, 2006.

[22] Di Palma P, Bolino F, D'Emilia G, et al., "Force sensor based on FBG embedded in silicone rubber." IEEE Sensors J, vol. 23, no. 2, pp. 1172-1178, Jan 2022.

[23] Awodeyi AE, Alty SR, Ghavami M, "Median filter approach for removal of baseline wander in photoplethysmography signals." In: 2013 European Modelling Symposium. IEEE, 2013.

[24] Xiang HY, Xu JX, Xie X, et al., "Calibration of pulse wave transit time method in blood pressure measurement based on the korotkoff sound delay time." In: World Congress on Medical Physics and Biomedical Engineering May 26-31, 2012, Beijing, China. Springer Berlin Heidelberg, 2013.

[25] Hughes DJ, Haynes D, Swallow M, et al., “Measurements of Young's modulus of elasticity of the canine aorta with ultrasound,” Ultrason Imaging, vol. 1, no. 4, pp. 356-367, Oct 1979.

[26] Proença J, Ferreira J, Roque A, et al., "Is pulse transit time a good indicator of blood pressure changes during short physical exercise in a young population?." In: 2010 Annual International Conference of the IEEE Engineering in Medicine and Biology. IEEE, 2010.

[27] Bramwell JC, Hill AV, "The velocity of pulse wave in man, " Proc R Soc B Biol Sci, vol. 93, no. 652, pp. 298-306, Apr 1922.
[28] Kao YH, Wu YS, Tsai CC, et al., “Towards maximizing the sensing accuracy of a cuffless, optical blood pressure sensor using a high-order front-end filter,” Microsyst Technol, vol. 24, no. 11, pp. 4621-4630, Nov 2018.

[29] Vlachopoulos C, O'Rourke M, Nichols WW, "McDonald's blood flow in arteries: theoretical, experimental and clinical principles." CRC Press, 2011.

[30] Shcherbina A, Mattsson CM, Waggott D, et al., "Accuracy in wrist-worn, sensor-based measurements of heart rate and energy expenditure in a diverse cohort." J Pers Med, vol. 7, no. 2, p. 3, Jun 2017.

[31] Stergiou GS, Alpert BS, Mieke S, et al., “Validation protocols for blood pressure measuring devices in the 21st century,” J Clin Hypertens, vol. 20, no. 7, pp. 1096–1099, Jul 2018.

[32] American National Standard for Electronic or Automated Sphygmomanometers, ANSI/AAMI SP 10 2002, Arlington, VA, USA: Association for the Advancement of Medical Instrumentation, 2002.

[33] O’Brien E, Atkins N, Stergiou G, et al., “European Society of Hypertension International Protocol revision 2010 for the validation of blood pressure measuring devices in adults,” Blood Press Monit, vol. 15, no. 1, pp. 23–38, Feb 2010.

[34] O'Brien E, Mee F, Atkins N, et al., “The British Hypertension Society protocol for the evaluation of automated and semi-automated blood pressure measuring devices with special reference to ambulatory systems,” J Hypertens, vol. 8, no. 7, pp. 607–619, Jul 1990.

[35] Pierdomenico SD, Lapenna D, Di Tommaso R, et al., "Prognostic value of different indices of blood pressure variability in hypertensive patients." Am J Hypertens, vol. 22, no. 8, pp. 842-847, Aug 2009.