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Canadian Journal of Veterinary Research... Oct 2018The objective of this study was to characterize arterial blood pressure (BP) measurements obtained by using 2 indirect methods, oscillometry and Doppler ultrasonic...
The objective of this study was to characterize arterial blood pressure (BP) measurements obtained by using 2 indirect methods, oscillometry and Doppler ultrasonic sphygmomanometry, in conscious goats. Agreement between systolic BP yielded by these 2 methods was then assessed. Sixty female dairy goats aged from 1.5 to 11.8 y (median: 5.5 y) were examined in a standing position with a cuff placed on the tail. All goats had a severe arthritic form of caprine arthritis-encephalitis. Three to 5 repeated measurements of each BP type were averaged for each goat and considered as a final measurement. With oscillometry, systolic blood pressure (O-SBP), diastolic blood pressure, and mean blood pressure, as well as heart rate (HR) were measured, while only systolic blood pressure was measured with Doppler (D-SBP). The O-SBP did not correlate with D-SBP [correlation coefficient = 0.24, = 0.067]; the mean difference (± standard deviation) was 24.5 ± 26.3 mmHg and limits of agreement were from -27.2 mmHg [95% confidence interval (CI): -39.0, -15.4 mmHg] to 76.1 mmHg (95% CI: 64.3, 87.9 mmHg). No significant linear correlation was found between any BPs and HR ( -0.10 to 0.22) or age ( -0.26 to 0.07) of the goats. The study showed that, while BP could be measured in conscious goats using both oscillometry and Doppler ultrasonic sphygmomanometry, the results obtained were so inconsistent that these methods could not be used interchangeably.
Topics: Animals; Blood Pressure; Blood Pressure Determination; Female; Goats; Heart Rate; Oscillometry; Sphygmomanometers; Ultrasonography, Doppler
PubMed: 30363283
DOI: No ID Found -
Pulmonology 2018Tracheal stenosis is a rare and challenging disease. Bronchoscopy is the gold standard for diagnosis and assessment but brings inherent risks. Spirometry is commonly... (Comparative Study)
Comparative Study
INTRODUCTION AND OBJECTIVES
Tracheal stenosis is a rare and challenging disease. Bronchoscopy is the gold standard for diagnosis and assessment but brings inherent risks. Spirometry is commonly used to access obstructions but is not always feasible due to patient related factors. We therefore considered impulse oscillometry (IOS) as a non-invasive method to quantify airway obstruction and its potential use for diagnosis and follow-up of tracheal stenosis.
MATERIALS AND METHODS
Patients with confirmed tracheal stenosis were recruited between January 1st, 2015 and December 31st, 2016. Before bronchoscopy, all subjects underwent IOS and spirometry; for patients submitted to interventional bronchoscopy the same techniques were also performed after the procedure. We assessed the correlation between IOS measurements and airway narrowing as well as between IOS and spirometry values.
RESULTS
Twenty-one patients were included. Tracheal narrowing was inversely correlated with X5% (r -0.442, p 0.045) and positively correlated with FEV1/PEF (r 0.467, p 0.033). The stenosis length was inversely correlated with PEF and PEF% (r -0.729, p=0.001 and r -0.707, p=0.002, respectively). There was a strong correlation between spirometric and IOS values. We did not find any significant differences between pre- and post-intervention IOS values for patients assessed after interventional bronchoscopy.
CONCLUSIONS
Our study showed a weak correlation between X5% and tracheal narrowing making it unclear whether IOS can be used for physiological assessment of patients with tracheal stenosis. Stenosis length correlated with PEF making it a potential predictor of successful surgical approach. The correlation between IOS and spirometric values makes IOS a potential alternative in patients with suspected tracheal stenosis who are not able to perform spirometry. Larger scale studies should clarify the role of IOS in this pathology.
Topics: Adolescent; Adult; Aged; Bronchoscopy; Female; Humans; Male; Middle Aged; Oscillometry; Respiratory Function Tests; Spirometry; Tracheal Stenosis; Young Adult
PubMed: 29627402
DOI: 10.1016/j.pulmoe.2017.12.006 -
The Netherlands Journal of Medicine Oct 2003Devices measuring blood pressure oscillometrically at the wrist are becoming more and more popular. These devices are small, easy to handle and can measure blood... (Review)
Review
Devices measuring blood pressure oscillometrically at the wrist are becoming more and more popular. These devices are small, easy to handle and can measure blood pressure without the need to undress. However, few of the wrist devices have been validated properly, i.e. according to internationally accepted protocols. In this article current literature on wrist blood pressure measuring devices is presented. The importance of positioning the wrist at heart level for accurate measurements is stressed.
Topics: Automation; Blood Pressure Determination; Equipment Failure Analysis; Humans; Hypertension; Oscillometry; Self Care; Sphygmomanometers; Wrist
PubMed: 14708908
DOI: No ID Found -
The Canadian Veterinary Journal = La... Apr 2020Arterial blood pressure is a common parameter evaluated in conscious and anesthetized veterinary species. Non-invasive blood pressure measurement techniques, such as... (Review)
Review
Arterial blood pressure is a common parameter evaluated in conscious and anesthetized veterinary species. Non-invasive blood pressure measurement techniques, such as Doppler ultrasonic flow detector and oscillometry, are attractive in certain animals due to their availability and ease of use. The greatest limitation to non-invasive blood pressure monitoring can be its inaccuracy, particularly in hypotensive or hypertensive patients and in certain species. Part 1 of this 2-part review summarizes the current techniques available to non-invasively measure arterial blood pressure in animals and discusses validation of non-invasive devices. Part 2 summarizes the veterinary literature that evaluates the use of non-invasive blood pressure measurement techniques in conscious and anesthetized species and develops general conclusions for proper use and interpretation of data from non-invasive blood pressure devices.
Topics: Animals; Arterial Pressure; Blood Pressure; Blood Pressure Determination; Hypotension; Oscillometry
PubMed: 32255821
DOI: No ID Found -
Anaesthesiology Intensive Therapy 2022Mean arterial pressure (MAP) is a key haemodynamic variable monitored in critically ill patients. The advantages of oscillometric noninvasive blood pressure (NIBP)... (Meta-Analysis)
Meta-Analysis Review
Mean arterial pressure (MAP) is a key haemodynamic variable monitored in critically ill patients. The advantages of oscillometric noninvasive blood pressure (NIBP) measurement are its easy and fast methodology; however, the accuracy and the precision of this measurement in critically ill patients is constantly debated. We performed a systematic review and meta-analysis of observational studies comparing oscillometric NIBP methods with invasive arterial pressure (IAP) measurements. We included studies of adult critically ill patients, which evaluated MAP in the same patient by both NIBP and IAP at any site. We included only studies comparing simultaneous measurements of arterial pressure by NIBP and IAP, reporting their results using mean difference and SD of agreement. The main outcome was to define the bias of the MAP measured by NIBP over the IAP measurement. The quality of the studies was analysed by the QUADAS 2 tool. Seven studies and 1593 patients were included in the main analysis. The oscillometric NIBP method had a mean value of -1.50 mmHg when compared with IAP (95% CI: -3.34 to 0.35; I2 = 96% for random effects model, P < 0.01). The limits of agreement for MAP varied between -14.6 mmHg and +40.3 mmHg. NIBP had an adequate accuracy regarding MAP measurements by oscillometry. Limits of agreement may thus narrow the clinical applicability in scenarios in which there is a need for a more precise management of blood pressure.
Topics: Adult; Humans; Blood Pressure; Blood Pressure Determination; Oscillometry; Critical Illness; Arterial Pressure
PubMed: 36734453
DOI: 10.5114/ait.2022.123120 -
Science Translational Medicine Mar 2018High blood pressure (BP) is a major cardiovascular risk factor that is treatable, yet hypertension awareness and control rates are low. Ubiquitous BP monitoring... (Randomized Controlled Trial)
Randomized Controlled Trial
High blood pressure (BP) is a major cardiovascular risk factor that is treatable, yet hypertension awareness and control rates are low. Ubiquitous BP monitoring technology could improve hypertension management, but existing devices require an inflatable cuff and are not compatible with such anytime, anywhere measurement of BP. We extended the oscillometric principle, which is used by most automatic cuff devices, to develop a cuff-less BP monitoring device using a smartphone. As the user presses her/his finger against the smartphone, the external pressure of the underlying artery is steadily increased while the phone measures the applied pressure and resulting variable-amplitude blood volume oscillations. A smartphone application provides visual feedback to guide the amount of pressure applied over time via the finger pressing and computes systolic and diastolic BP from the measurements. We prospectively tested the smartphone-based device for real-time BP monitoring in human subjects to evaluate usability ( = 30) and accuracy against a standard automatic cuff-based device ( = 32). We likewise tested a finger cuff device, which uses the volume-clamp method of BP detection. About 90% of the users learned the finger actuation required by the smartphone-based device after one or two practice trials. The device yielded bias and precision errors of 3.3 and 8.8 mmHg for systolic BP and -5.6 and 7.7 mmHg for diastolic BP over a 40 to 50 mmHg range of BP. These errors were comparable to the finger cuff device. Cuff-less and calibration-free monitoring of systolic and diastolic BP may be feasible via a smartphone.
Topics: Adult; Blood Pressure; Blood Pressure Determination; Female; Humans; Male; Middle Aged; Oscillometry; Smartphone
PubMed: 29515001
DOI: 10.1126/scitranslmed.aap8674 -
Blood Pressure Monitoring Jun 2019In longitudinal research studies with follow-up examinations, the devices used to measure phenotypes may change over time. When a device change occurs, the two devices... (Comparative Study)
Comparative Study
BACKGROUND
In longitudinal research studies with follow-up examinations, the devices used to measure phenotypes may change over time. When a device change occurs, the two devices should be calibrated to each other to ensure that measurements are comparable. This paper details the Jackson Heart Study (JHS) blood pressure (BP) comparability study.
PARTICIPANTS AND METHODS
During its second clinic exam (2005-2008), the JHS switched from a random-zero sphygmomanometer (RZS) BP measurement device to an oscillometric device (OD). During this exam, BP measurements from both an RZS and an OD were taken simultaneously in 2117 participants for the purpose of calibration. Five methods for calibrating systolic BP (SBP) and diastolic BP (DBP) were considered: ignoring the change, ordinary least squares regression, adding the average difference, Deming regression, and robust regression.
RESULTS
Using the RZS and OD, the mean (SD) SBP was 125.5 (19.2) and 126.5 (19.9), respectively, and the mean (SD) DBP was 76.4 (10.6) and 74.0 (11.0), respectively. The correlation between RZS and the OD was 0.90 for SBP and 0.80 for DBP. The prevalence of high BP and hypertension and associations with albuminuria were similar when applying each of the five calibration methods. Robust regression was chosen for calibration, giving the following equations:(Equation is included in full-text article.)These equations had a higher R statistic than using calibration equations from the Coronary Artery Risk Development in Young Adults Study and the Heinz Nixdorf Recall Study.
CONCLUSIONS
The JHS BP data have been calibrated using the above equations for use in future analyses.
Topics: Adult; Albuminuria; Blood Pressure; Blood Pressure Determination; Calibration; Female; Humans; Hypertension; Longitudinal Studies; Male; Middle Aged; Oscillometry; Prevalence; Sphygmomanometers; Young Adult
PubMed: 30998553
DOI: 10.1097/MBP.0000000000000379 -
Scientific Reports Aug 2019Impedance, or oscillometry, measurements of the respiratory system can generate information about the function of the respiratory system not possible with traditional...
Impedance, or oscillometry, measurements of the respiratory system can generate information about the function of the respiratory system not possible with traditional spirometry. There are currently several instruments on the market using different perturbations. We have compared a new respiratory oscillometry instrument, the tremoflo, with Impulse Oscillometry (IOS). Patients with a physician's diagnosis of chronic obstructive lung disease (COPD) and healthy subjects were recruited. They underwent assessment of respiratory function with oscillometry using the IOS and tremoflo devices and the resulting impedance data from the two methods were compared. The two devices were also tested against a reference respiratory phantom with variable resistances. Whereas both devices detected impairments in the patients' lung function commensurate with small airways pathology, the tremoflo appeared to be more sensitive than the IOS. We found systematic differences between the two instruments especially for reactance measurements where the area over the reactance curve (AX) was significantly lower with the IOS compared with the tremoflo (p < 0.001). Moreover, the agreement between the two devices was reduced with increasing severity of the disease as determined with a Bland-Altman test. Testing both instruments against a respiratory phantom unit confirmed that the resistance measured by the tremoflo compares closely with the known resistance of test loads, whereas the IOS' resistance correlated with a test load of 0.19, kPa.s.L at higher loads it deviated significantly from the known resistance (p < 0.0028). We conclude that the absolute values measured with the two devices may not be directly comparable and suggest that differences in the calibration procedures might account for the differences.
Topics: Adult; Female; Humans; Male; Middle Aged; Oscillometry; Pulmonary Disease, Chronic Obstructive; Respiratory Function Tests
PubMed: 31406190
DOI: 10.1038/s41598-019-48039-x -
Journal of Feline Medicine and Surgery Mar 2024Systemic arterial hypertension is a common occurrence and can have serious adverse consequences in cats. Therefore, measuring blood pressure is very important. There are...
OBJECTIVES
Systemic arterial hypertension is a common occurrence and can have serious adverse consequences in cats. Therefore, measuring blood pressure is very important. There are many indirect blood pressure measurement devices available. This study compared Doppler, oscillometric (petMAP Graphic II, SunTech Vet20, the Cardell Insight-X0000) and high-definition oscillometry devices for the non-invasive measurement of blood pressure in conscious cats.
METHODS
In this prospective study, blood pressure was measured in 32 cats using the different devices according to the recommendations of the American College of Veterinary Internal Medicine Consensus Statement. Blood pressures (systolic blood pressure [SBP], diastolic blood pressure [DBP], mean arterial pressure [MAP]), time to complete measurements, number of attempts needed, coefficient of variation (CV) between the blood pressure measurements of the different devices, ease of completing measurements and apparent stress level of the cat were assessed.
RESULTS
There was a significant difference between devices in the time taken to obtain blood pressure readings and the number of attempts necessary to obtain six reliable measurements. The CV of the Doppler device was significantly smaller than that of the rest of the devices, but there were no other differences between the devices. The mean SBP, DBP and MAP measured by the petMAP device were significantly higher than the measurements from the other devices. The perceived ease of measurement was not significantly different between the various machines. The perceived level of stress of measurement with the Doppler device was significantly higher compared with the other devices but did not lead to an increased SBP.
CONCLUSIONS AND RELEVANCE
Using a Doppler device to measure blood pressure in conscious cats is fast, relatively easy and gives reliable results. A disadvantage is that the Doppler device can only measure SBP, while oscillometric devices also provide DBP and MAP. However, in veterinary medicine, systolic hypertension is considered the most relevant.
Topics: Cats; Animals; Blood Pressure; Ultrasonics; Oscillometry; Prospective Studies; Blood Pressure Determination
PubMed: 38546192
DOI: 10.1177/1098612X241231471 -
Philosophical Transactions of the Royal... May 2005The architecture of the brain is characterized by a modular organization repeated across a hierarchy of spatial scales-neurons, minicolumns, cortical columns, functional... (Review)
Review
The architecture of the brain is characterized by a modular organization repeated across a hierarchy of spatial scales-neurons, minicolumns, cortical columns, functional brain regions, and so on. It is important to consider that the processes governing neural dynamics at any given scale are not only determined by the behaviour of other neural structures at that scale, but also by the emergent behaviour of smaller scales, and the constraining influence of activity at larger scales. In this paper, we introduce a theoretical framework for neural systems in which the dynamics are nested within a multiscale architecture. In essence, the dynamics at each scale are determined by a coupled ensemble of nonlinear oscillators, which embody the principle scale-specific neurobiological processes. The dynamics at larger scales are 'slaved' to the emergent behaviour of smaller scales through a coupling function that depends on a multiscale wavelet decomposition. The approach is first explicated mathematically. Numerical examples are then given to illustrate phenomena such as between-scale bifurcations, and how synchronization in small-scale structures influences the dynamics in larger structures in an intuitive manner that cannot be captured by existing modelling approaches. A framework for relating the dynamical behaviour of the system to measured observables is presented and further extensions to capture wave phenomena and mode coupling are suggested.
Topics: Brain; Brain Mapping; Data Interpretation, Statistical; Humans; Models, Neurological; Nonlinear Dynamics; Oscillometry; Time Factors
PubMed: 16087448
DOI: 10.1098/rstb.2005.1643