便携式睡眠呼吸暂停低通气监测仪的研制
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摘要
阻塞性睡眠呼吸暂停综合征是一种严重威胁人类健康的常见多发病,只是近30年来才逐渐被人们关注。是一种由于某些原因而导致上呼吸道阻塞,睡眠时有呼吸暂停,伴有缺氧、鼾声、白天嗜睡等症状的一种较复杂的疾病。它不仅影响人们的睡眠质量,还会引起高血压、心脑血管疾病等疾病,对人的健康危害极大。目前,医学上对阻塞性睡眠呼吸暂停综合征的预防、诊断和治疗受到了广泛的重视,因此研制一种便携式睡眠监测仪在临床上具有重要的意义。
本文基于光电容积法和朗伯-比尔定律,提出了脉率和血氧饱和度的算法,设计并实现了一种低功耗、体积小、价格便宜、适合家庭使用的睡眠呼吸暂停低通气监测仪。硬件设计上,通过NELLCOR指夹透射式血氧探头和相关驱动电路来采集人体脉搏波信号；通过HONEYWELL呼吸传感器提取鼻呼吸压力信号；设计并实现了人机交互式接口、时钟模块、存储模块、USB数据通信模块等。在软件设计上,在IAR平台上采用C430和汇编的混合编程完成底层驱动程序,实现了数据的采集、预处理、显示、存储和传输,实现了脉率和血氧饱和度的检测算法,同时,采用Visual C++作为开发平台,设计并实现了测试仪配套的PC机端软件系统,实现了生理参数的实时显示与健康评估。
通过系统测试表明,该监测仪各功能模块运行良好,整体功能完备,能有效提取脉搏波和呼吸信号,算出脉率和血氧饱和度,并结合呼吸信号,对人体睡眠状况进行评估。
Obstructive sleep apnea syndrome(OSAS) is a serious threat to human health,which attracted widespread concern in the past 30 years. OSAS is sleep-breathing disorder characterized by a set of episodes of total and/or partial cessation of respiratory airflow while patient is asleep, also coupled with low oxygen saturation, snore and somnolence during the daytime. OSAS not only affects people's sleep quality, but also can lead to hypertension, cardiovascular diseases, etc. It becomes more and more important in the prevention, diagnosis and treatment of OSAS presently. Consequently, There is important significance in clinical to develop a portable sleep detecting device.
Based on the method of photoelectric plethysmography and the Beer-Lambert Law, the algorithm of pulse frequence and oxygen saturation was present, the portable sleep detecting device characterized by low power dissipation, small size, cheap and suitable for family use was developed. In the part of hardware design,photoplethysmogram was detected with NELLCOR probe and relevant driver circuit; nasal respiratory wave was detected with HONEYWELL respiratory pressure sensor; In the part of software design, the driver is written with the C language on the platform of IAR. The fuction of data gathering, preprocedding, display, save and comminication was realized. The patient monitoring and diagnosis system was designed on the platform of VC++ 6.0, which can display the detected data and generate diagnosis result report.
The system testing and clinical experiment was established, the sleep detecting device work well, which can detect photoplethysmogram and respiratory wave effectively, work out the pulse frequency and oxygen saturation, generate diagnosis report of sleep finally.
本文基于光电容积法和朗伯-比尔定律,提出了脉率和血氧饱和度的算法,设计并实现了一种低功耗、体积小、价格便宜、适合家庭使用的睡眠呼吸暂停低通气监测仪。硬件设计上,通过NELLCOR指夹透射式血氧探头和相关驱动电路来采集人体脉搏波信号；通过HONEYWELL呼吸传感器提取鼻呼吸压力信号；设计并实现了人机交互式接口、时钟模块、存储模块、USB数据通信模块等。在软件设计上,在IAR平台上采用C430和汇编的混合编程完成底层驱动程序,实现了数据的采集、预处理、显示、存储和传输,实现了脉率和血氧饱和度的检测算法,同时,采用Visual C++作为开发平台,设计并实现了测试仪配套的PC机端软件系统,实现了生理参数的实时显示与健康评估。
通过系统测试表明,该监测仪各功能模块运行良好,整体功能完备,能有效提取脉搏波和呼吸信号,算出脉率和血氧饱和度,并结合呼吸信号,对人体睡眠状况进行评估。
Obstructive sleep apnea syndrome(OSAS) is a serious threat to human health,which attracted widespread concern in the past 30 years. OSAS is sleep-breathing disorder characterized by a set of episodes of total and/or partial cessation of respiratory airflow while patient is asleep, also coupled with low oxygen saturation, snore and somnolence during the daytime. OSAS not only affects people's sleep quality, but also can lead to hypertension, cardiovascular diseases, etc. It becomes more and more important in the prevention, diagnosis and treatment of OSAS presently. Consequently, There is important significance in clinical to develop a portable sleep detecting device.
Based on the method of photoelectric plethysmography and the Beer-Lambert Law, the algorithm of pulse frequence and oxygen saturation was present, the portable sleep detecting device characterized by low power dissipation, small size, cheap and suitable for family use was developed. In the part of hardware design,photoplethysmogram was detected with NELLCOR probe and relevant driver circuit; nasal respiratory wave was detected with HONEYWELL respiratory pressure sensor; In the part of software design, the driver is written with the C language on the platform of IAR. The fuction of data gathering, preprocedding, display, save and comminication was realized. The patient monitoring and diagnosis system was designed on the platform of VC++ 6.0, which can display the detected data and generate diagnosis result report.
The system testing and clinical experiment was established, the sleep detecting device work well, which can detect photoplethysmogram and respiratory wave effectively, work out the pulse frequency and oxygen saturation, generate diagnosis report of sleep finally.
引文
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[2]Balakrishnan G, Burli D, Burk R J et al. Comparison of a sleep quality index between normal and obstructive sleep apnea patients[C]. Medicine and Biology 27th Annual Conference.2005:1154-1157.
[3]Bar A, Pillar G, Dvir I et al. A comparison of evaluation of a portable device based on peripheral arterial tone for unattended home sleep studies[J]. Chest.2003, 123:695-703.
[4]Estivill A, Bov A, Garca-Borreguero J, et al. Consensus on drug treatment, definition and diagnosis for insomnia[J]. Clin Drug Invest.2003, (23):351-385.
[5]李明娴,黄席珍.睡眠呼吸暂停综合征的家庭监测[J].中国老那些杂志,20(3)：129-131.
[6]杨跃平,高建武,邵雪辉.睡眠呼吸暂停综合征及检测方法[J].张家口医学院学报,2003,20(3)：59-61
[7]吴海锋,许锋,陈建华等.热释电式睡眠呼吸暂停监测[J].红外技术,2004,26(4)：31-33.
[8]赵忠新.睡眠医学发展史[J].中国现代神经疾病杂志.2006,6(1)：6-10
[9]韩芳.睡眠医学—一门新兴的边缘交叉学科[J].医学研究杂,2006,35(12)：5-7.
[10]张熙.睡眠医学是当前亟待发展的学科[J].中华老年心脑血管病杂志,2005,7(5)：289-291
[11]何权瀛.目前我国睡眠呼吸医学面临的一些困难和问题[J].中国呼吸与危重监护杂志,2007,6(2)：81
[12]刘艳骄.国际睡眠医学的发展趋势及我们的对策[J].中国中医药.2005,4(3)：54-55.
[13]强朝晖(译).睡商—清醒的头脑来自健康的睡眠[M].2009：17-19.
[14]齐志勇,张治平,呼和牧仁等.多导睡眠仪(PSG)在阻塞性睡眠呼吸暂停低通气综合征(OSAHS)中的临床应用价值[J].当代医学(学术版),2007,(6)：6-8.
[15]Flemons W W. Obstructive sleep apnea[J]. The New England Journal of Medicine.2002,347(7):498-504
[16]王丽,韩芳.睡眠呼吸暂停低通气综合症的诊断及鉴别诊断[J].中华全科医师杂志,2005,4(4)：204-206.
[17]张宁.无创血氧饱和度监测系统及其关键技术研究[D].中国：第一军医大学, 2004.5:1.
[18]韩芳,陈尔璋,魏海琳等.夜间血氧饱和度监测对睡眠呼吸暂停综合征的诊断价值[J].中华结核和呼吸杂志,1999,22(6)：332-334
[19]何金昌,李永祥,焦水平等.单纯血氧饱和度监测对睡眠呼吸暂停综合征的初筛诊断价值[M],临床内科杂志,2006,(3)：210
[20]王春艳,李静,韩旭等.动态血氧饱和度监测在睡眠呼吸暂停低通气综合征诊断中的应用[J].2006,23(10)：698-700
[21]Inci Cilesiz, Mursel Aksoy. Fundamentals of biomedical engineering. Project Pulse oximetry,2005.12:1-20.
[22]陈和,黄智伟.无损伤血氧饱和度测量系统研究[J].南华大学学报(理工版),2002,16(2)：41-44.
[23]Lee J, Jung W, Kang I. Design of filter to reject motion artifact of pulse oximetry[J]. Computer Stnadards & Interafees,2004,26 (3):241-249.
[24]高遵伯.基于DSP的脉搏血氧饱和度测量仪的研制[D].中国：国防科学技术大学,2002.1.
[25]Ahmed M, Patel P Nirav, Rosen I. Portable Monitors in the Diagnosis of Obstructive Sleep Apnea[J]. Chest,2007,132(5):1672-1677
[26]刘光达,郭维,朱平等.基于容积波分析的血氧饱和度测量系统[J].激光与红外,2009,39(2)：169-172.
[27]黄建新,刘怀.监护用脉搏式血氧饱和度检测模块的研制[B].南京师范大学学报.2006,6(1)：17-21.
[28]郝连旺,宋涛.呼吸信号检测方法的研究[J].微纳电子技术,2007,44(7)：12-16.
[29]Sen I, Kahya P Y. A multi-channel device for respiratory sound data acquisition and transient detection[C]. Acquisition and Transient Detection,2005.9:6658-6661.
[30]Lee M E, Kim H N, Trand T N, et al. Respiratory rate detection algorithms by photoplethysmography signal processing[C].30th Annual International IEEE EMBS Conference,2008.8:1140-1144.
[31]Gollee H, Chen W. Real-time detection of respiratory activity using an inertial measrement unit[C]. Proceedings of the 29th annual international conference of the IEEE EMBS.2007.8:2230-2234.
[32]席涛,杨国胜,汤池.呼吸信号检测技术的研究进展[J].医疗卫生装备,2004,25(12)：26-29.
[33]Ayappa I, Norman R G, Suryadevaram, et al. Compaison of limited monitoring using a nasal-cannula flow signal to full polysomnography in sleep-disordered breathing[J]. Sleep,2004,27(6):1171-1179.
[34]Teichtahl H, Cunnington D, Cherry G, et al. Scoring polysomnography respiratory events:the utility of nasal pressure and oro-nasal thermal sensor recordings [J]. Sleep Med,2003,4(5):419-425. 4:419-425.
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