Blood Pressure Measurement Research Papers (original) (raw)

Young CC, Mark JB, White W, DeBree A, Vender JS, Fleming A. Clinical evaluation of continuous noninvasive blood pressure monitoring: accuracy and tracking capabilities. J Clin Monit 1995;11:245-252 ABSTRACT. A continuous, noninvasive device for blood pressure measurement using pulse transit time has been recently introduced. We compared blood pressure measurements determined using this device with simultaneous invasive blood pressure measurements in 35 patients undergoing general endotracheal anesthesia. Data were analyzed for accuracy and tracking ability of the noninvasive technique, and for frequency of unavailable pressure measurements by each method.

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- Biomedical Engineering, Blood Pressure, Calibration, Clinical

This paper presents a comparative performance analysis of various trend detection methods developed using fuzzy logic, statistical, regression, and wavelet techniques. The main contribution of this paper is the introduction of a new method that uses noise rejection fuzzy clustering to enhance the performance of trend detection methodologies. Furthermore, another contribution of this work is a comparative investigation that produced systematic guidelines for the selection of a proper trend detection method for different application requirements. Examples of representative physiological variables considered in this paper to examine the trend detection algorithms are: 1) blood pressure signals (diastolic and systolic); and 2) heartbeat rate based on RR intervals of electrocardiography signal. Furthermore, synthetic physiological data intentionally contaminated with various types of real-life noise has been generated and used to test the performance of trend detection methods and develop noise-insensitive trend-detection algorithms.

- by Ziren Lu
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- Algorithms, Biomedical Engineering, Fuzzy Logic, Time Series

Novel sensors and instrumentation are currently being investigated with the intended application of determining the concentration of hemoglobin and other optically absorbing compounds in blood using non-invasive methods. In order to measure concentration, the mass or amount of a compound must be known in addition to the volume of liquid. In principle, it may be possible to estimate hemoglobin concentration from a change in optical absorbance occurring over the cardiac cycle divided by a corresponding change in measured blood volume during the cycle measured from peripheral tissue, e.g. the finger or ear. Electrical and optical sensors were evaluated in vitro using a tissue phantom and an absorbing liquid medium. The effect of changes in optical absorption and pulse pressure on the capacitance and optical absorbance were studied.

- by Justin Phillips
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- Biochemistry, Computer Science, Materials Science, Medicine

Communications t~d'~valuerla pr~valence des complications vasculaires chez des hypertendus avec un HAP et chez des hypertendus essen• tiels suivis~l'hOpital Broussais. Entre 1994 et 1996, Ie diagnostic d'HAP a ete etabli chez 124 patients... more

- by Jean Ribstein
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- Interest, Blood Pressure, Circadian Rhythm, Ambulatory

The ability to predict episodes of acute hypotension (abnormal drop in arterial blood pressure) would be of immense benefit to the healthcare community, and is therefore a focus of research in both medical and engineering domains. This paper presents the use of Hidden Markov Models to predict the onset of acute hypotension, using blood pressure measurements over time. Our use of HMMs has been motivated by their ability to characterize sequential/temporal trends in a given time signal. This lends the ability to infer the health status based on blood pressure information collected over an interval of time, rather than just instantaneous measurements. We have tested the proposed technique on standard physiological signal datasets available online and have obtained promising results. As part of a bigger project, we see potential in the proposed technique being used in real time health monitoring systems.

- by Abhishek Singh
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- Physiology, Biomedical Engineering, Speech Acoustics, Signal Analysis

Compared with the history of national guideline development, the science attached to implementation of guidelines is relatively new. Effectiveness of a highly evidence-based guideline, such as the 8th Joint National Committee recommendations on the treatment of high blood pressure, depends on successful translation into clinical practice. Implementation relies on several steps: clear and executable guideline language, audit and feedback attached to education of practitioners charged with carrying out the guidelines, team-based care delivery, credibility of blood pressure measurement, and measures to address therapeutic inertia and medication adherence. An evolving role of the electronic health record and patient empowerment are developments that will further promote implementation of the hypertension guideline. Further research will be needed to assess the efficacy and cost effectiveness of various implementation tools and strategies.

- by Daniel Lackland
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- Communication, Medication Adherence, Electronic Health Records, California

the aim of this study is to investigate erectile response to injection administration of Epimedium brevicornum Maxim (EbM) and its power spectral analysis in rats. Adult male Sprague-Dawley (SD) rats were used in this study. Under pentobarbital sodium anesthesia, the penile Intracavernous pressure (ICP) was monitored. Intracavernous administration of doses 3000g/0.lmL of EbM extract was done. Continuous power spectral analysis of electrocardiogram (ECG), blood pressure (BP) signals .Frequency-domain analysis of the stationary RR interval, systolic pressure variation was performed to quantify the high-frequency power (HF), low-frequency power (LF)-to-HF ratio (LF/HF), and normalized LF (LF%) of Heart Rate Variability (HRV), Blood Pressure Variability (BPV). The results of this study suggest that intracavernous administration of EbM extract may elicit penile erection in terms of a significant increase in ICP in the rat. These results suggest that EbM extract may facilitate decrease sympathovagal balance or to reflect sympathetic modulations activities of the heart and activities penile erection function. But have no significant differences in BPV parameters.

- by Shuenn-Tsong Young
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- Biomedicine, Low Frequency, High Frequency, Heart rate variability

This article aims to compare alternative methods for estimating the quality of blood pressure measurements. Traditional within-subject variance estimates in mixed analysis of variance models are compared to multiple-group multitrait-multimethod models, which are a particular case of mean-and-covariancestructure conÿrmatory factor analysis models. Conÿrmatory factor analysis models belong to the family of structural equation models and were speciÿcally developed to analyse psychosociological traits measured by tests or surveys, but they have also proved suitable for evaluating the quality of blood pressure measurements. Conÿrmatory factor analysis models are less restrictive and provide more detailed information than traditional approaches, enable researchers to compute weighted averages of individual measures with optimal measurement quality, make it easier to correct the biasing e ects of measurement error on the results of substantive studies, and make the use of equivalent replicated measures unnecessary under certain conditions. Copyright ? 2001 John Wiley & Sons, Ltd.

- by Germà Coenders
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- Mathematics, Statistics, Medicine, Factor analysis

Blood pressure (BP) is one of the important vital signs that need to be monitored for personal healthcare. This paper describes the method developed by the authors to measure systolic blood pressure from pulse transit time (PTT) Pulse transit time is the time taken for the arterial pulse pressure wave to travel from the aortic valve to a peripheral site. It is usually measured from the R wave on the electrocardiogram to a photoplethysmography signal. PTT is inversely proportional to blood pressure. This method does not require an air cuff and only a minimal inconvenience of attaching electrodes and LED/photo detector sensors on a subject. Twenty three healthy subjects (age 18-60 yrs) were studied. Blood pressure measurement is carried out using pulse transit time and is compared with sphygmomanometry, the reference standard and the oscillometric based automatic BP measuring machine. The results show that the standard deviation of their differences was around 3 mmHg. The developed pu...

- by Nivedita Daimiwal
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- Bioinformatics, Medicine, Standard Deviation, Blood Pressure

This study investigated whether attitudes and
emotions towards robots predicted acceptance of a healthcare
robot in a retirement village population. Residents (n = 32) and
staff (n = 21) at a retirement village interacted with a robot for
approximately 30 minutes. Prior to meeting the robot,
participants had their heart rate and blood pressure measured.
The robot greeted the participants, assisted them in taking their
vital signs, performed a hydration reminder, told a joke, played
a music video, and asked some questions about falls and
medication management.
Participants were given two questionnaires; one before and
one after interacting with the robot. Measures included in both
questionnaires were the Robot Attitude Scale (RAS) and the
Positive and Negative Affect Schedule (PANAS). After using the
robot, participants rated the overall quality of the robot
interaction. Both residents and staff reported more favourable
attitudes (p < .05) and decreases in negative affect (p < .05)
towards the robot after meeting it, compared with before
meeting it. Pre-interaction emotions and robot attitudes,
combined with post-interaction changes in emotions and
robot attitudes, were highly predictive of participants’
robot evaluations (R = .88, p < .05). The results suggest both
pre-interaction emotions and attitudes towards robots, as well as
experience with the robot, are important areas to monitor and
address in influencing acceptance of healthcare robots in
retirement village residents and staff. The results support an
active cognition model that incorporates a feedback loop based
on re-evaluation after experience.

- by Chandimal Jayawardena
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- Negative Affect, Blood Pressure, Heart rate, Feedback loop

Background: Despite having the largest population in Africa, Nigeria has no accurate population based data to plan and evaluate eye care services. A national survey was undertaken to estimate the prevalence and determine the major causes... more

- by Jiya Mehra
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- Ophthalmology, Photography, Blindness, Service Quality

The aim of this study was to assess a wide range of health-related behaviours, beliefs concerning the importance of behaviours for health, and health knowledge, using a standardized protocol suitable for translation and administration in different countries of Europe. An inventory was developed from previous literature for the assessment of substance use, positive health practices, diet and eating habits, driving behaviour and preventive health care, beliefs concerning the importance of 25 activities for health, and knowledge about the influence of seven factors (including smoking, alcohol and diet) on major diseases. The first phase of the study involved administration of the inventory to approximately 200 male and 200 female university students aged 18-30 in 20 European countries. This report concerns data collected from 419 students in the U.K., together with analyses of short-term response stability.

- by Andrew Steptoe
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- Sociology, Anthropology, Health Behavior, Health Care

Avaliar critérios empregados para a medida da pressão arterial em artigos científicos de periódicos brasileiros. Métodos -Foram analisados 223 artigos de 18 revistas médicas nacionais, publicados entre 1989 e 1994, identificando-se, em cada um, o tipo de esfigmomanômetro utilizado, a calibração do equipamento, o tamanho da bolsa de borracha, a posição e descanso prévio do paciente, as fases que determinam a pressão sistólica e diastólica, e o número de medidas realizadas. Resultados -Não houve referência nos artigos analisados dos seguintes aspectos: tipo de esfigmomanômetro em 51%, calibração do aparelho em 82%, dimensão da bolsa de borracha em 64%, fases que determinam as pressões sistólica e diastólica em 49% e número de medidas realizadas em 52%.

- by Isa Gomes
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- Blood Pressure Measurement

There is a relation, not always linear, between the blood pressure and the pulse duration, obtained from photoplethysmography (PPG) signal. In order to estimate the blood pressure from the PPG signal, in this paper the Artificial Neural Networks (ANNs) are used. Training data were extracted from the Multiparameter Intelligent Monitoring in Intensive Care waveform database for better representation of possible pulse and pressure variation. In total there were analyzed more than 15000 heartbeats and 21 parameters were extracted from each of them that define the input vector for the ANN. The comparison between estimated and reference values shows better accuracy than the linear regression method and satisfy the American National Standards of the Association for the Advancement of Medical Instrumentation.

- by Francesco Lamonaca
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- Computer Science, Neural Networks, Artificial Neural Networks, Blood Pressure

Aims. The aim of this study was to examine whether there is any difference between BP readings with patients crossing a leg at the knee level and uncrossing during BP measurement. Background. It is clear that numerous factors influence an individual's blood pressure (BP) measurement. However, guidelines for accurately measuring BP inconsistently specify that the patient should keep feet flat on the floor. Design. Repeated measures. Method. Using a mercury-filled column sphygmomanometer, BP was measured at uncrossed leg position, crossed leg position and again at uncrossed leg position in 283 unmedicated or medicated patients. Three experienced nurses specially trained for the study performed BP measurements. Results. The results indicated that BP increased significantly with the crossed leg position. Systolic and diastolic BP significantly increased approximately 10 and 8 mmHg, respectively. Conclusion. Crossing the leg at knee results in a significant increase in BP. Relevance to clinical practice. Leg position during measurement of BP should be standardised and mentioned in publications.

- by Roger Watson
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- Psychology, Nursing, Cardiovascular, Hypertension

Aim: To test the effect of positioning the arm on the armrest of a common chair, below the officially recommended right atrial level, on the blood pressure (BP) readings in a group of outpatients. Patients and methods: A group of 69 patients (58 hypertensives; 39 males; mean ± s.d. age 54.1 ± 16.0 years) participated in the present study. BP and heart rate values obtained in each of the following two positions were compared: (1) sitting with the arms supported on the arm-rests of the chair and (2) sitting with the arms supported at the level of the mid-sternum (the approximation of the right atrial level). BP was measured simultaneously at both arms, with a mercury sphygmomanometer at the right arm and with an automatic oscillometric device at the left arm. Results: Both the systolic and diastolic BPs were sig

- by Thien Nguyen Long Nhat Thien
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- Medicine, Human, Hypertension, Blood Pressure

A more efficient newer algorithm of detecting systolic and diastolic pressure of human body along with a complete package of an effective user-friendly embedded programmable blood pressure monitoring system has been proposed in this paper to reduce the overall workload of medical personals as well as to monitor patient's condition more conveniently and accurately. Available devices for measuring blood pressure have some problems and limitations in case of both analog and digital devices. The sphygmomanometer, being analog device, is still being used widely because of its reliability and accuracy over digital ones. But it requires a skilled person to measure the blood pressure and obviously not being automated as well as time consuming. Our proposed system being a microcontroller based embedded system has the advantages of the available digital blood pressure machines along with a much improved form and has higher accuracy at the same time. This system can also be interfaced with computer through serial port/USB to publish the measured blood pressure data on the LAN or internet. The device can be programmed to determine the patient's blood pressure after each certain interval of time in a graphical form. To sense the pressure of human body, a pressure to voltage transducer is used along with a cuff in our system. During the blood pressure measurement cycle, the output voltage of the transducer is taken by the built-in ADC of microcontroller after an amplifier stage. The recorded data are then processed and analyzed using the effective software routine to determine the blood pressure of the person under test. Our proposed system is thus expected to certainly enhance the existing blood pressure monitoring system by providing accuracy, time efficiency, user-friendliness and at last but not the least the 'better way of monitoring patient's blood pressure under critical care' all together at the same time.

- by Tasnuva Faruk
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- Algorithms, Image Processing, Embedded Systems, Microcontrollers

Relationships between anger and anxiety have been examined in adults but less frequently in children. This investigation explored relationships among trait anxiety, trait anger, anger expression patterns, and blood pressure in children. The participants were 264 third-through sixth-grade children from five elementary schools who completed Jacob's Pediatric Anger and Anxiety Scale and Jacob's Pediatric Anger Expression Scale and had their blood pressure measured. Data were analyzed using descriptive and correlational statistics and hierarchical regression. Results have implications for the way in which anxiety and anger are perceived in children and the importance of teaching children to deal with emotions. D

- by Marti Rice
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- Nursing, Anger, Anxiety, Child

... Revati Shriram, Asmita Wakankar, Nivedita Daimiwal, Dipali Ramdasi Department of Instrumentation and Control Cummins College of Engineering for Women ... The authors are grateful to Dr. Madhuri Khambete and Prof AD Gaikwad for their... more

- by Geert Morren
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- Bioinformatics, Medicine, Standard Deviation, Blood Pressure

- by Geert Morren
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- Bioinformatics, Medicine, Standard Deviation, Blood Pressure

Objectives The use of low-dose amlodipine has not yet been well established in the elderly. This study therefore aimed to evaluate the efficacy and tolerability of low-dose amlodipine in elderly patients with Joint National Committee VI stage I or II hypertension. Patients and methods Sixty-five hypertensive individuals (aged 66.3±5.3 years) received amlodipine 2.5mg per day for 12 weeks before and

- by Fernando Nobre
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- Brazil, Treatment Outcome, Hypertension, Low Dose

Great significant progress has been made in the development of biomedical microdevices in recent years, and these devices are now playing an important role in diagnosis and therapy. This paper presents a review of applications of microelectromechanical systems (MEMS) devices for in vivo diagnosis and therapy, and endoscopicand catheter-based interventions. MEMS technology has enabled the further development of advanced biomedical microdevices for use in the human body by integration of sensors, actuators, and electronics into small medical devices for use in the body. In this paper, we discuss three categories of such devices: navigation systems, sensors and actuators for catheters and endoscopes, and other minimally invasive techniques. A brief introduction to principles, device structures, packaging, and related issues is presented.

- by M. Esashi
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- Surgery, Microfluidics, Biosensors, Packaging
- by Timo Tuomisto
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- Health Care, Blood Pressure, Patient Monitoring, Sleep

Two cardiovascular parameters of emerging interest suitable for estimation of non-invasive, beat-to-beat, and without cu, blood pressure parameters are pulse width (P) and pulse transit time (PTT). In this study the performance of both parameters in estimating beat-to beat systolic blood pressure (SBP) and diastolic blood pressure (DBP) is analyzed. The overall data set used in the study includes synchronous electrocardiogram signal (ECG), pulse photoplethysmography signal (PPG) and continuous blood pressure signal of 16 healthy subjects during tilt table test, which provokes signficant changes in SBP and DBP due to postural changes.

- by J. Aguiló and +1
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- Cardiovascular system, Photoplethysmography, Blood Pressure Measurement

Objective Studies have demonstrated that hypertension remains inadequately managed throughout the world, with lack of adherence to BP-lowering medication being a major factor. The aim of the present study was to evaluate if a... more

P-Health, a future health model that can be described as a 6-P's paradigm, aims to provide low cost and high quality health care via redesigning care practice and networking information systems at different levels. To realise p-Health, a multi-level health information system has to be developed for the processing, storage, transmission, acquisition and retrieval (P-STAR) of health information that spans multiple temporal and spatial scales and consists of multi-modality. This paper uses wearable devices, which have to be miniaturised, integrated, networked, digitalised, smart and standardised (MINDSS), as examples to illustrate how two or more P-STAR technologies are integrated together to implement a specific health care application under p-Health. In particular, standardisation of MINDSS devices that required a new measurement principle, such as the calibration procedure of cuff-less blood pressure measurement devices, is discussed.

- by Wenbo Gu
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- Medical Informatics, Health Informatics, Health Care, Hong Kong

A micro-controller based embedded system has been designed and developed to monitor and control the operation of various types of power supplies required for the super conducting cyclotron, from the front panel as well as from the remote terminal. The main objective of this development is to provide support for the supervisory control of the indigenous power supplies developed to energize different magnets like main magnet, trim coils etc. for the operation of the cyclotron.

- by tanushyam bhattacharjee
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- Analytical Chemistry, Mechatronics, Control Systems, Microcontrollers

Beat detection algorithms have many clinical applications including pulse oximetry, cardiac arrhythmia detection, and cardiac output monitoring. Most of these algorithms have been developed by medical device companies and are proprietary. Thus, researchers who wish to investigate pulse contour analysis must rely on manual annotations or develop their own algorithms. We designed an automatic detection algorithm for pressure signals that locates the first peak following each heart beat. This is called the percussion peak in intracranial pressure (ICP) signals and the systolic peak in arterial blood pressure (ABP) and pulse oximetry (SpO 2 ) signals. The algorithm incorporates a filter bank with variable cutoff frequencies, spectral estimates of the heart rate, rank-order nonlinear filters, and decision logic. We prospectively measured the performance of the algorithm compared to expert annotations of ICP, ABP, and SpO 2 signals acquired from pediatric intensive care unit patients. The algorithm achieved a sensitivity of 99.36% and positive predictivity of 98.43% on a dataset consisting of 42,539 beats.

- by Tran Thong
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- Algorithms, Artificial Intelligence, Cardiology, Biomedical Engineering

Human voice accents have been shown to affect people's perceptions of the speaker, but little research has looked at how synthesized voice accents affect perceptions of robots. This research investigated people's perceptions of three synthesized voice accents. Three male robot voices were generated: British (UK), American (US), and New Zealand (NZ). In study one, twenty adults listened through headphones to a recorded script repeated in the three different accents, rated the nationality, roboticness, and overall impression of each voice, and chose their preferred accent. Study two used these voices on a healthcare robot to investigate the influence of accent on user perceptions of the robot. Ninety-one individuals were randomized to one of three conditions. In each condition they interacted with a healthcare robot that assisted with blood pressure measurement but the conditions differed in the accent the robot spoke with. In study one, each accent was correctly identified. There was no difference in impression ratings of each voice, but the US accent was rated as more robotic than the NZ accent, and the UK accent was preferred to the US accent. Study two showed that people randomized to the NZ accent had more positive feelings towards the robot and rated the robot's overall performance as higher compared to the robot with the US voice. These results suggest that the employment of a less robotic voice with a local accent may positively affect user perceptions of robots.

- by Elizabeth Broadbent and +1
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- Social Robotics, New Zealand, Positive Affect, User Perception

Most of automatic blood pressure measurement devices on the market implement an oscillometric method. This paper highlights the need for standardized calibration procedures for these devices in order to reduce logistical difficulties, timeconsuming processes, and high costs involved in clinical validations. A critical overview of researchers' and manufacturers' proposals to answer this need is presented as a contribution to the IEEE P1721 project for a new standard on Objective Measurement of Systemic Arterial Blood Pressure in Humans.

We evaluated clinical implications of the white-coat effect (WCE) in cardiovascular (CV) risk stratification in the primary prevention setting of a Lipid Clinic. We compared home self blood pressure measurement (SBPM) with office blood pressure (BP) readings and BP measured by a nurse before and after the visit on consecutive subjects, free of previous CV diseases, attending at a Lipid Clinic for a first visit. Additionally, we evaluated whether and to what extent the difference between these measurements affect the 10-year cardiovascular risk calculated according to current guidelines.

- by Mario Bo and +1
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- Atherosclerosis, Cardiovascular Risk, Hypertension, Blood Pressure

We present a novel model 1 for measurement of the arterial pulse from the Superficial Temporal Artery (STA) using passive thermal Infra Red (IR) sensors. The proposed approach has a physical and physiological basis and as such is of fundamental nature. Thermal IR camera is used to capture the heat pattern from superficial arteries, and a blood vessel model is used to describe the pulsatile nature of the blood flow. A multresolution wavelet-based signal analysis approach is used to extract the arterial pulse waveform, which lends itself to various physiological measurements. We validate the results using a traditional contact vital-sign monitor as a ground truth. Eight people of different age, race and gender have been tested in our study consistent with IRB approval. The resultant arterial pulse waveforms exactly matched the ground-truth readings. The essence of our approach is the automatic detection of Region Of arterial pulse Measurement (ROM), from which the arterial pulse waveform is extracted. To the best of our knowledge, the correspondence between non-contact thermal IR imaging based measurements of the arterial pulse in the time domain and traditional contact approaches has never been reported in the literature.

The effect of dental checkups on blood pressure was investigated. In 27 normotensive patients (13 men and 14 women) aged 22 to 64 years (mean 39.75 +/- 10.5 years), a 26-hour continuous, noninvasive blood pressure registration was carried out. Of each patient at least 175 blood pressure measurements were registered during these 26 hours, giving a total amount of 4725 blood pressure measurements. A dental checkup appointment with the family dentist was included. Blood pressure values displayed the well-known diurnal variation, but the visit to the dental surgeon was not accompanied by a rise in blood pressure. There was no significant difference between the blood pressure values during the 26-hour period and those during the checkup period. During a rest period after the dental checkup, neither the systolic nor the diastolic pressure fell to any degree in relation to the 26-hour values or the visit to the surgeon.

- by L. Abraham-Inpijn
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- Anxiety, Hypertension, Questionnaires, Physical examination

Although estimation of average blood pressure is commonly done with oscillometric measurements, confidence intervals (CIs) for systolic blood pressure (SBP) and diastolic blood pressure (DBP) are not usually estimated. This paper adopts bootstrap methodologies to build CI from a small sample set of measurements, which is a situation commonly encountered in practice. Three bootstrap methodologies, namely, nonparametric percentile bootstrap, standard bootstrap, and bias-corrected and accelerated bootstrap are investigated. A two-step methodology is proposed based on pseudomeasurements using bootstrap principles to first derive the pseudomaximum amplitudes and then the pseudoenvelopes (PEs). The SBP and DBP are estimated using the new relationships between mean cuff pressure and PE and then the CIs for such estimates are obtained. In order to reduce the amount of processing, a single-step methodology that directly derives PE using bootstrap principles is also presented. Application of the proposed methodology on an experimental data set of 85 patients with five sets of measurements for each patient has yielded a narrower CI than the currently available conventional methods such as Student's t-distribution method.

- by Hilmi Dajani
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- Statistical Analysis, Estimation Theory, Blood Pressure, Bias Correction
- by Eoin O'Brien
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- Self Care, Hypertension, Europe, Blood Pressure

Patient monitor modules have various inputs for vital function measurement. We can practice many of these measurements with some students in the laboratory of biomedical engineering. However, invasive blood pressure (IBP) measurement demonstration is impossible. This paper is dealing with design and realization of a programmable invasive blood pressure simulator. This device is able to generate programmable behavior of voltage signal with correspond to blood pressure curve. The user communication interface of the device allows choosing the type of generated signal by LCD and 4 push buttons. The wide spectrums of generated signals, which correspond to physiological or pathological blood pressure curves, are stored in a user programmable memory. The output connectors of the device can be directly connected to a patient monitor IBP module input. Invasive blood pressure measurement simulation for educational purposes and calibrating the patients monitors are the general usages of the de...

- by Jan Kijonka
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- Engineering, Biomedical Engineering, Blood Pressure, Patient Monitoring

An electrocardiogram (ECG) / blood pressure (BP) telemonitor consisting of comprehensive integration of various electrical engineering concepts, devi ces, and methods was developed. This Personal Digital Assistant-based (PDAbased) system focused on integration of biopotential amplifiers, photoplethysmographic measurement of blood pressure, microcontroller devices, programming methods, wireless transmission, signal filtering and analysis, interfacing, and long term memory devices (24 hours) to develop a state-of-the-art ECG/BP telemonitor. These instrumentation modules were developed and tested to realize a complete and compact system that could be deployed to assist in telemedicine applications and heart rate variability studies. The specific objective of this device was to facilitate the long term monitoring and recording of ECG and blood pressure signals. This device was able to acquire ECG/BP waveforms, transmit them wirelessly to a PDA, save them onto a compact flash memory, and display them on the LCD screen of the PDA. It was also capable of calculating the heart rate (HR) in beats per minute , and providing systolic and diastolic blood pressure values.

- by Ricardo Parra
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- Electrical Engineering, Medicine, Microcontrollers, Heart rate variability

The objective of this study was to establish whether ambulatory blood pressure offers a better estimate of cardiovascular risk than does its clinical blood pressure counterpart in refractory hypertension. This prospective study assessed the incidence of cardiovascular events over time during an average follow-up of 49 months (range, 6 to 96). Patients were referred to specialized hypertension clinics (86 essential hypertension patients who had diastolic blood pressure Ͼ100 mm Hg during antihypertensive treatment that included three or more antihypertensive drugs, one being a diuretic). Twenty-four-hour ambulatory blood pressure monitoring (ABPM) was performed at the time of entrance. End-organ damage was monitored yearly, and the incidence of cardiovascular events was recorded. Patients were divided into tertiles of average diastolic blood pressure during activity according to the ABPM, with the lowest tertile Ͻ88 mm Hg (LT, nϭ29), the middle tertile 88 to 97 mm Hg (MT, nϭ29), and the highest tertile Ͼ97 mm Hg (HT, nϭ28). While significant differences in systolic and diastolic ambulatory blood pressures were observed among groups, no differences were observed at either the beginning or at the time of the last evaluation for office blood pressure. During the last evaluation, a progression in the end-organ damage score was observed for the HT group but not for the two other groups. Twenty-one of the patients had a new cardiovascular event; the incidence of events was significantly lower for the LT group (2.2 per 100 patient-years) than it was for the MT group (9.5 per 100 patient-years) or for the HT group (13.6 per 100 patient-years). The probability of event-free survival was also significantly different when comparing the LT group with the other two groups (LT versus MT log-rank, PϽ.04; LT versus HT log-rank, PϽ.006). The HT group was an independent risk factor for the incidence of cardiovascular events (relative risk, 6.20; 95% confidence interval, 1.38 to 28.1, PϽ.02). Higher values of ambulatory blood pressure result in a worse prognosis in patients with refractory hypertension, supporting the recommendation that ABPM is useful in stratifying the cardiovascular risk in patients with refractory hypertension. (Hypertension. 1998;31:712-718.)

- by peter gheeraert
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- Cardiovascular Risk, Prospective studies, Hypertension, Blood Pressure
- by G. Vandenhoven and +1
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- Self Care, Electrocardiography, Echocardiography, Hypertension

This research sought to evaluate the contribution of simulation to the development of a fundamental nursing skill, blood pressure measurement. Year one nursing students at UCOL, New Zealand (n ¼ 75) and the University of Huddersfield, England (n ¼ 55) completed questionnaires about their confidence/ competence levels in blood pressure measurement at the conclusion of the simulation sessions, and again after their first clinical placement. Registered nurses who worked with those students (n ¼ 22 UCOL, n ¼ 21 University of Huddersfield) also completed assessments of the students' competence with both electronic and manual blood pressure during their placement.

- by Karen Ousey
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- Nursing, England, United Kingdom, Self Efficacy

Clinic blood pressure measurements have only limited ability to determine which hypertensive patients are at greatest risk of cardiovascular events. Ambulatory blood pressure monitoring allows for noninvasive measurement of blood pressure throughout the 24-hour period. This may help to clarify discrepancies between blood pressure values obtained in and out of the clinic and confirm the presence of white-coat hypertension, broadly defined as an elevated clinic blood pressure but a normal ambulatory blood pressure. Ambulatory blood pressure values have been shown to have a better relationship to cardiovascular morbidity and mortality and end-organ damage than clinic blood pressure values. Further, patients with white-coat hypertension appear to be at greater risk of cardiovascular morbidity and end-organ damage than a normotensive population, although they are at less overall risk than a hypertensive population. Hypertensive heart disease is characterized by diastolic dysfunction, increased left ventricular mass, and coronary flow abnormalities. Left ventricular hypertrophy increases the risk of coronary heart disease, congestive heart failure, stroke, ventricular arrhythmias, and sudden death. A variety of invasive and noninvasive techniques are described herein that measure left ventricular mass, diastolic function, and coronary blood flow abnormalities. Most antihypertensive treatments promote regression of left ventricular hypertrophy and reversal of diastolic dysfunction, which may decrease symptoms of congestive heart failure and improve survival.

- by Joseph Diamond
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- Risk, Cardiovascular disease, Echocardiography, Sudden Death

Abstract-Homecare is the provision of health care services to patients in their own home. One of the main purposes of homecare telemedicine is to develop a wireless, low-cost and use-friendly system which allows patients to measure their... more

- by Khoi Nguyen
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- Health Care, Electronics, Medicine, Home Care
- by Stefano Cagnoni
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- Hypertension, Blood Pressure, Technique, Regression Analysis