Continuous ambulatory electrocardiography among workers exposed to methylmethacrylate

Summary Methylmethacrylate (MMA), a widely used monomer in the manufacture of acrylic polymers, has been reported to cause cardiac troubles in industrial workers. The effects of MMA on the heart was assessed by continuous ambulatory electrocardiographic records. The study was performed in 22 occupationally exposed workers and in 18 healthy controls. Our study did not support the hypothesis that MMA is responsible for cardiomyodystrophy. However, supraventricular and ventricular ectopic beats were significantly more frequent among exposed workers versus controls (P < 0.01). Moreover, repolarization changes such as large T waves were noted only in exposed workers (eight cases against none in the control group). Although there was no clear connection between MMA exposure and the recorded cardiac changes in the exposed group, the role of MMA cannot be totally excluded.     

地尔硫静脉滴注治疗冠心病心绞痛

目的：观察地尔硫Ｚｈｕｏ注射液静脉滴注治疗冠心病心绞痛的疗效。方法：８６例心绞痛患者分为两组，其中治疗组４６例，用地尔硫Ｚｈｕｏ５０ｍｇ加入５％葡萄糖液２５０ｍｌ中静滴，１次／ｄ，连续１０ｄ；对照组４０例用丹参液１６ｍｌ加入５％葡萄糖液２５０ｍｌ中静滴，１次／ｄ，连续１０ｄ。结果：治疗组症状控制总有效率９８％，患者心电图改善率６１％，明显高于对照组的３７％和２８％，地尔硫Ｚｈｕｏ改善心功能效果明显     

服用抗精神病药物的老年人与成年人心电图比较

目的：观察老年与成年精神病人服用抗精神病药物后的心电图（ＥＣＧ）改变。方法：８４例老年精神病病人（男性３５，女性４９例，年龄６３±ｓ３ａ）与１００例成年精神病病人（男性５０例，女性５０例，年龄４０±１０ａ），服用抗精神病药物前及服２ｍｏ以上的首次ＥＣＧ资料进行比较。抗精神病药包括吩噻嗪类、丁酰苯类及三环类抗抑郁剂和抗躁狂药等。结果：８４例老年病人中ＥＣＧ异常６３例（７５％），１００例成年人中ＥＣＧ异常４６例（４６％）（Ｐ＜０．０５）。结论：由于老年人服抗精神病药后易发生ＥＣＧ异常，因此开始剂量宜低，增量要小，严密监测心脏功能。     

Design and development of a digital stethoscope encapsulation for simultaneous acquisition of phonocardiography and electrocardiography signals: the SmartHeart case study

Abstract

The stethoscope is a major symbol of modern medicine. It is used for diagnosis of different conditions and enables physicians to listen to internal body sounds. Electrocardiography was only introduced in medicine in the beginning of the twentieth century. Today measuring heart’s electrical activity is also fundamental cardiac diseases diagnosis. Although performed with independent devices, requiring physician and patient presence in the same physical space, in combination they enhance cardiovascular assessment. In this paper, a digital stethoscope encapsulation was designed, adding new functionality to this advanced medical device. Today wired and wireless communications enable different medical devices to share data and information, over long distances. Using low-cost hardware technologies, the encapsulation will add the ability to acquire and transmit via Bluetooth the Electrocardiographic activity, determined in the same cardiac focus and synchronised with the Phonocardiographic sound recordings. Several encapsulation concepts were developed and prototyped using 3D printing. They were easily fitted to the digital stethoscope and tested in a hospital environment for ergonomics, acoustic and electric signals acquisition. The best concept was chosen with the help of a physician’s opinion and the final prototype performance was very satisfactory.     

Prevalence and prognostic significance of cardiac arrhythmias detected by ambulatory electrocardiography in subjects 85 years of age

24 hour ambulatory electrocardiography was performed in a representativegroup of people born in 1897. Out of 73 people included in thestudy, 22 were without known heart disease, 15 had definiteischaemic heart disease (IHD) and 36 symptoms of possible cardiacorigin. An R-R interval in excess of 2000 ms was seen in only3 subjects and Wenckebach A-V block in only one. One subjectwithout a history of syncope had a nocturnal episode of completeA-V block with an escape interval of 8000 ms. The most strikingdifference between healthy subjects and patients with IHD wasthe higher number of patients with more than 1000 ventricularpremature beats (VPBs) per 24 hour and ventricular coupletscompared with the number of healthy subjects with such findings.At follow-up two years later 11% had died, with the highestmortality in patients with IHD (33%), and out of 8 patientswith IHD who had more than 1000 VPBs per 24 hour, 4 (50%) haddied compared with only one (14%) of those with less than 1000VPBs. Our results seem to indicate that more than 1000 VPBsper 24 hour is a very unusual finding in healthy 85 year oldindividuals. When it occurs in very old people, it is usuallyin connection with IHD, and in this setting it signifies a poorprognosis.     

计算机辅助的心血管信号检测和处理系统的研究

【目的】研制一个计算机辅助的心血管信号检测和处理系统。【方法】本系统的硬件设计采用奔腾 Ⅱ / 2 33多媒体微机系统 ,多路模 /数转换器和心电电极、心音传感器、脉搏波传感器及由运算放大器等构成相关的放大器及滤波器。本系统采用可视化编程环境构建系统结构和功能模块设计的方法 ,基于多媒体技术和小波变换原理 ,在 32位Windows平台下 ,利用可视化编程语言VisualC 6 0和多媒体著作工具Authorware等进行系统的软件设计。【结果】本系统能完成心电、心音、脉搏波信号检测和处理 ,并将结果以图、文、声并茂的形式显示、打印或播放 ,还具有病案管理和心音听诊多媒体计算机辅助教学功能。【结论】它是一个新型的多功能心血管信号检测和处理系统。     

基于体表生理信号的呼吸功能监测仪研制

目的：研制一款基于体表心电、膈肌电和胸阻抗信号的呼吸功能监测仪原理样机,可在家庭、医疗急救等场合实现对呼吸功能的持续监测。方法：以STM32F411VET6单片机开发系统为平台,用一对Ag/AgCl电极作为高频激励信号的输出和心电、胸阻抗信号的检测电极,另一对Ag/AgCl电极作为膈肌电信号检测电极,两对电极同时检测心电、膈肌电和胸阻抗信号。系统硬件主要包括心电信号检测电路、胸阻抗信号检测电路、膈肌电信号检测电路、恒流源激励电路以及微控制器。系统采用12 V可充电锂电池供电,模拟信号通过单片机A/D转换成数字信号,通过SDIO接口存储于SD卡。在完成样机制作和性能测试之后,采集13例因呼吸功能障碍实施机械通气患者和13例健康成年人的信号,计算15个与呼吸功能相关的参数,比较机械通气患者与健康对照组参数之间的差异,验证了呼吸功能监测仪的可靠性。结果：样机采集信号的信噪比>10 dB、共模抑制比>80 dB,样机漏电流<30μA。机械通气患者的吸气时间、呼气时间、潮气量、胸阻抗峰峰值、胸阻抗1 s变化量、膈肌电低频功率、膈肌电高频功率、高频比低频、膈肌放电面积、膈肌放电时...     

Monitoring normal and aberrant electrocardiographic activity from an endotracheal tube: Comparison of the surface,esophageal, and tracheal electrocardiograms

Introduction. We designed an endotracheal (ET) tube with orthogonally spaced ECG cuff electrodes. This ET tube was evaluated in dogs and sheep to determine (1) whether ECGs recorded from our tube were sufficient to make accurate clinical decisions concerning heart rate and rhythm; and (2) whether metallic cuff electrodes in direct contact with the trachea could induce mucosal burn injury during episodes of defibrillation.Methods. Using experimental animals, we obtained ECGs from their tracheae and compared our findings with ECGs obtained from surface and esophageal electrodes. The electrical activity of the heart was modified by increasing the depth of anesthesia, occluding the left coronary artery, and administering beta-adrenergic drugs. Before the dogs were euthanized, they were subjected to episodes of transthoracic and intrathoracic defibrillation at energy levels of 200 to 400 J. A postmortem pathological examination of the trachea was performed to determine the incidence of mucosal burn injury.Results. Tracheal electrocardiography provided valid information on heart-rate monitoring and certain morphology profiles. The R-R, PR, QRS, and QT intervals measured from the trachea had a correlation of 1.0, 0.96, 0.83, and 0.98, respectively, when compared with the same intervals obtained from surface electrodes. Two tracheae subjected to intrathoracic defibrillation at >300 J revealed evidence of minor burn injury. Some localized epithelium loss was displayed in all tracheae; we attributed this to tracheal intubation.Conclusion. Tracheal electrocardiography may be useful in trauma patients who require intubation where injury precludes placement of chest ECG electrodes.     

Monitoring during paediatric cardiac anaesthesia

Monitoring of paediatric anaesthesia has become increasingly more complex in recent years and this is particulary true of cardiac anaesthesia. The purpose of this review is to give a comprehensive update of published material related to both routine and specialized cardiac monitoring. Routine monitoring can be particularly affected by the alterations of cardiac rhythm, blood flow, cardiac output and oxygenation which result from the congenital heart abnormalities themselves, the type of surgery undertaken and the effects of cardiopulmonary bypass. The use of specialized monitoring is becoming more widespread, particularly in the areas of cerebral function, mixed venous oxygenation, cardiac output measurement and coagulation. In the last five years, with the development of smaller probes, a great deal has been published on transoesophageal echocardiography. The use of the current monitors of cerebral function still remains controversial despite the need for a monitor of adequate brain perfusion, reflecting the need for a great deal of further research in this area. This review will concentrate on particular areas which have seen the most profound changes and on monitoring that may form the standards of tomorrow. Finally, amongst all the technology, it should not be forgotten that the most important clinical monitor is the bedside clinical monitoring of the physicians themselves. Depuis quelques années, le monitorage de l’anesthésie pédiatrique devient déplus en plus complexe et tout particulièrement en anesthésie cardiaque. L’objectif de ce travail consiste à passer en revue la littérature actuelle qui traite du monitorage usuel et spécialisé. Le monitorage usuel peut être influencé par les modifications de la fréquence cardiaque, du courant sanguin, du débit cardiaque et de l’oxygénation provoqués par les anomalies cardiaques congénitales, du type de chirurgie et des retentissements de la circulation extracorporelle. L’utilisation du monitorage spécialisé est de plus en plus répandu et concerne particulièrement la circulation cérébrale, l’oxygénation du sang veineux mêlé, la mesure du débit cardiaque et la coagulation. Au cours des cinq dernières années, le développement de sondes plus petites a généré de nombreuses publications sur l’échocardiographie transoesophagienne. L’utilisation des moniteurs actuels de la fonction cérébrale demeure sujet à controverse bien qu ’un moniteur de perfusion cérébrale adéquat demeure toujours aussi essentiel, confirmant ainsi le besoin de recherches supplémentaires sur ce sujet. Ce survol se portera spécialement sur les champs d’activités qui ont connu les changements les plus profonds et sur le monitorage qui établira les standards du futur. Finalement, au milieu de cette technologie, il ne faut jamais oublier que le moniteur clinique le plus important se trouve au chevet du malade en la personne du médecin.     

181例大面积烧伤患者心电图分析

对武汉市第三医院烧伤科１９９３年～１９９７年１８１例住院的大面积烧伤患者早期心电图结果进行回顾分析。心电图正常者５３例（２９．３％）,心电图异常者１２８例（７０．７％）,其中以窦性心动过速居多,占８７例（６７％）,心肌受损或ＳＴ－Ｔ异常改变６５例（５１％）。心电图异常者病死率（５３％）比心电图正常者病死率（１１％）显著增高,提示：大面积烧伤患者早期心电图异常改变、尤其是有心肌损害或ＳＴ－Ｔ异常改变患者预后较差