Covariation and Temporal Stability of Peripheral and Brachial Blood Pressure Responses to Mental and Static Stress

Abstract Peripheral blood pressure measurement (Finapres technique) is a promising development in activation research. This paper tests and compares the temporal stability and covariation of peripheral and brachial blood pressure responses. Forty healthy subjects were tested four times at intervals of 1 day, 1 week, and 1 month. The tasks employed were two mental tasks (mental arithmetic and a Color Word Test) and a static (fingergrip) task. Recorded physiological parameters were peripheral and brachial systolic (SBP) and diastolic blood pressure (DBP). Mean peripheral SBP was about 20 mmHg higher than brachial SBP, but the difference between the DBP measures was negligible. Correlations between peripheral and corresponding brachial BP resting levels were low, with coefficients below 0.30. The correlations between peripheral and brachial SBP and DBP were higher for reactivity (change) scores (0.46-0.82) than for resting scores. Several types of inter- and intraindividual covariation were calculated to provide a deeper understanding of the relationship between the physiological parameters with respect to their dynamics. Temporal stability of peripheral BP level scores was lower (0.37-0.57) than for brachial BP (0.59-0.77), but the stability of the change scores was similar for both BP techniques. The results show that it is important to distinguish between several aspects of the mutual relationship between peripheral and brachial BP measures. Peripheral BP measurements are not suited to assess the BP level of a subject, but they are very useful to assess cardiovascular reactivity.

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Combined deep CNN–LSTM network-based multitasking learning architecture for noninvasive continuous blood pressure estimation using difference in ECG-PPG features

Scientific Reports ◽

10.1038/s41598-021-92997-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Da Un Jeong ◽

Ki Moo Lim

Keyword(s):

Blood Pressure ◽

Blood Pressure Measurement ◽

Patient Specific ◽

Peak Time ◽

Simultaneous Prediction ◽

Deep Cnn ◽

Pressure Estimation ◽

The Difference ◽

Blood Pressure Estimation ◽

Continuous Blood Pressure

AbstractThe pulse arrival time (PAT), the difference between the R-peak time of electrocardiogram (ECG) signal and the systolic peak of photoplethysmography (PPG) signal, is an indicator that enables noninvasive and continuous blood pressure estimation. However, it is difficult to accurately measure PAT from ECG and PPG signals because they have inconsistent shapes owing to patient-specific physical characteristics, pathological conditions, and movements. Accordingly, complex preprocessing is required to estimate blood pressure based on PAT. In this paper, as an alternative solution, we propose a noninvasive continuous algorithm using the difference between ECG and PPG as a new feature that can include PAT information. The proposed algorithm is a deep CNN–LSTM-based multitasking machine learning model that outputs simultaneous prediction results of systolic (SBP) and diastolic blood pressures (DBP). We used a total of 48 patients on the PhysioNet website by splitting them into 38 patients for training and 10 patients for testing. The prediction accuracies of SBP and DBP were 0.0 ± 1.6 mmHg and 0.2 ± 1.3 mmHg, respectively. Even though the proposed model was assessed with only 10 patients, this result was satisfied with three guidelines, which are the BHS, AAMI, and IEEE standards for blood pressure measurement devices.

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Measurement of digital blood pressure after local cooling

Journal of Applied Physiology ◽

10.1152/jappl.1977.43.5.907 ◽

1977 ◽

Vol 43 (5) ◽

pp. 907-910 ◽

Cited By ~ 129

Author(s):

S. L. Nielsen ◽

N. A. Lassen

Keyword(s):

Blood Pressure ◽

Blood Pressure Measurement ◽

Proximal Phalanx ◽

Systolic Pressure ◽

Threshold Temperature ◽

Local Cooling ◽

The Difference ◽

Arterial Tone ◽

Percent Decrease ◽

Finger Pressure

A double-inlet plastic cuff was designed for local cooling and systolic blood pressure measurement on the middle phalanx of the fingers. With a tourniquet on the proximal phalanx of one finger, cooling for 5 min made the digital artery temperature equal the skin temperature. The difference between the systolic pressure in a control finger and in the cooled finger give the reopening pressure in the digital arteries. At 30, 25, 20, 15, and 10 degrees C, respectively the percent decrease of the finger pressure was 0.2 (0.2), 1.5 (2.5), 8.5 (3.7), 11.4 (3.4), and 15.3 (3.1) in normal young women. In patients with primary or secondary Raynaud's phenomenon, the arterial tone showed an abrupt increase that most often led to complete closure of the digital arteries. The pathological response was expressed as an increased threshold temperature or a well-defined closing temperature that showed only small variations during standardized conditions.

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Influence on Calculated Blood Pressure of Measurement Posture for the Development of Wearable Vital Sign Sensors

Journal of Sensors ◽

10.1155/2017/8916596 ◽

2017 ◽

Vol 2017 ◽

pp. 1-10 ◽

Cited By ~ 6

Author(s):

Shouhei Koyama ◽

Hiroaki Ishizawa ◽

Akio Sakaguchi ◽

Satoshi Hosoya ◽

Takashi Kawamura

Keyword(s):

Blood Pressure ◽

Calibration Curve ◽

Pressure Measurement ◽

Pulse Wave ◽

Blood Pressure Measurement ◽

Wave Signal ◽

Fbg Sensor ◽

Pressure Calculation ◽

Measurement Height ◽

The Difference

We studied a wearable blood pressure sensor using a fiber Bragg grating (FBG) sensor, which is a highly accurate strain sensor. This sensor is installed at the pulsation point of the human body to measure the pulse wave signal. A calibration curve is built that calculates the blood pressure by multivariate analysis using the pulse wave signal and a reference blood pressure measurement. However, if the measurement height of the FBG sensor is different from the reference measurement height, an error is included in the reference blood pressure. We verified the accuracy of the blood pressure calculation with respect to the measurement height difference and the posture of the subject. As the difference between the measurement height of the FBG sensor and the reference blood pressure measurement increased, the accuracy of the blood pressure calculation decreased. When the measurement height was identical and only posture was changed, good accuracy was achieved. In addition, when calibration curves were built using data measured in multiple postures, the blood pressure of each posture could be calculated from a single calibration curve. This will allow miniaturization of the necessary electronics of the sensor system, which is important for a wearable sensor.

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Is Ankle–Brachial Blood Pressure Measurement of Clinical Utility for Asymptomatic Elderly?

Journal of Clinical Epidemiology ◽

10.1016/s0895-4356(01)00374-2 ◽

2001 ◽

Vol 54 (10) ◽

pp. 971-972 ◽

Cited By ~ 3

Author(s):

Lewis H. Kuller

Keyword(s):

Blood Pressure ◽

Pressure Measurement ◽

Clinical Utility ◽

Blood Pressure Measurement ◽

Brachial Blood Pressure

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Blood pressure variations and low blood pressure values at home after hospital discharge in older hypertensives

European Journal of Preventive Cardiology ◽

10.1177/1741826711403067 ◽

2011 ◽

Vol 19 (3) ◽

pp. 460-466

Author(s):

Marco Astengo ◽

Martina Bonetto ◽

Gianluca Isaia ◽

Monica Comba ◽

Gianfranco Fonte ◽

...

Keyword(s):

Blood Pressure ◽

Hospital Discharge ◽

Terminal Illness ◽

Blood Pressure Measurement ◽

University Teaching ◽

Antihypertensive Regimen ◽

Low Blood Pressure ◽

Study Population ◽

The Difference ◽

At Home

Background: Blood pressure (BP) variations occurring after hospital discharge in a population of older hypertensives have not been previously investigated. Design: elderly (≥65 years) hypertensives admitted to the geriatric acute ward of a university-teaching hospital were enrolled in this prospective observational study. Methods: Exclusion criteria were terminal illness, discharge to institution, and changes in antihypertensive regimen. BP was recorded in the emergency room, at ward admission, daily during hospital stay, and at discharge. Home self blood pressure measurement was performed after discharge. Results: The study population included 106 patients. There was a significant decrease in systolic BP (SBP) and diastolic BP (DBP) throughout the study time points. SBP and DBP decreased after discharge (from 135.1 ± 15.0 to 131.5 ± 16.1 mmHg and from 77.2 ± 8.4 to 71.6 ± 8.7 mmHg, respectively), the difference being significant only for DBP ( p = 0.000). We further observed higher prevalence of critically low BP values (SBP <120 mmHg and DBP <70 mmHg) at home (23.6% and 48.1%, respectively) compared to discharge (8.5% and 9.4%, p = 0.006 and p = 0.000, respectively). Conclusions: We observed a decrease in BP values, and particularly DBP values, after hospital discharge, in a sample of older hypertensives. Critically low BP values were observed at home in a high proportion of subjects, suggesting wise use of antihypertensive therapy at discharge and early monitoring of BP values at home.

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Automated Versus Manual Blood Pressure Measurement: A Randomized Crossover Trial in the Emergency Department of a Tertiary Care Hospital in Karachi, Pakistan: Are Third World Countries Ready for the Change?

Open Access Macedonian Journal of Medical Sciences ◽

10.3889/oamjms.2016.076 ◽

2016 ◽

Vol 4 (3) ◽

pp. 404-409 ◽

Cited By ~ 3

Author(s):

Kanaan Mansoor ◽

Saba Shahnawaz ◽

Mariam Rasool ◽

Huwad Chaudhry ◽

Gul Ahuja ◽

...

Keyword(s):

Blood Pressure ◽

Pressure Measurement ◽

Blood Pressure Measurement ◽

P Value ◽

Care Hospital ◽

Pressure Measurements ◽

The Mean ◽

The Difference ◽

Manual Blood Pressure ◽

Mercury Sphygmomanometer

BACKGROUND: Hypertension has proven to be a strong liability with 13.5% of all mortality worldwide being attributed to elevated blood pressures in 2001. An accurate blood pressure measurement lies at the crux of an appropriate diagnosis. Despite the mercury sphygmomanometer being the gold standard, the ongoing deliberation as to whether mercury sphygmomanometers should be replaced with the automated oscillometric devices stems from the risk mercury poses to the environment.AIM: This study was performed to check the validity of automated oscillometric blood pressure measurements as compared to the manual blood pressure measurements in Karachi, Pakistan.MATERIAL AND METHODS: Blood pressure was recorded in 200 individuals aged 15 and above using both, an automated oscillometric blood pressure device (Dinamap Procare 100) and a manual mercury sphygmomanometer concomitantly. Two nurses were assigned to each patient and the device, arm for taking the reading and nurses were randomly determined. SPSS version 20 was used for analysis. Mean and standard deviation of the systolic and diastolic measurements from each modality were compared to each other and P values of 0.05 or less were considered to be significant. Validation criteria of British Hypertension Society (BHS) and the US Association for the Advancement of Medical Instrumentation (AAMI) were used. RESULTS: Two hundred patients were included. The mean of the difference of systolic was 8.54 Â± 9.38 while the mean of the difference of diastolic was 4.21 Â± 7.88. Patients were further divided into three groups of different systolic blood pressure <= 120, > 120 to = 150 and > 150, their means were 6.27 Â± 8.39 (p-value 0.175), 8.91 Â± 8.96 (p-value 0.004) and 10.98 Â± 10.49 (p-value 0.001) respectively. In our study 89 patients were previously diagnosed with hypertension; their difference of mean systolic was 9.43 Â± 9.89 (p-value 0.000) and difference of mean diastolic was 4.26 Â± 7.35 (p-value 0.000).CONCLUSIONS: Systolic readings from a previously validated device are not reliable when used in the ER and they show a higher degree of incongruency and inaccuracy when they are used outside validation settings. Also, readings from the right arm tend to be more precise.

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Meditation Practice Improves Short-Term Changes in Heart Rate Variability

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17062128 ◽

2020 ◽

Vol 17 (6) ◽

pp. 2128 ◽

Cited By ~ 1

Author(s):

Kang-Ming Chang ◽

Miao-Tien Wu Chueh ◽

Yi-Jung Lai

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Heart Rate Variability ◽

Physiological Parameters ◽

The Other ◽

Meditation Practice ◽

Short Term ◽

Face To Face ◽

Before And After ◽

The Difference

Background: It is well known that meditation improves the physical and psychological condition of its practitioners. This study investigated the heart rate variability response of meditation practitioners in two Chan master teaching environments, namely face-to-face and video classes. Methods: Experimental sessions were conducted, one featuring face-to-face classes and the other featuring video classes. The difference in participants’ physiological parameters (blood pressure and heart rate variability) between the two experimental sessions was determined. In the first session, physiological parameters were recorded twice, before and after one teaching course, and the second session took place one month after the first. The first and second sessions had 45 and 27 participants, respectively. Those involved in the first experiment had no experience with meditation, whereas participants in the second experiment had practiced meditation for an average of 9 years (range = 1 to 27 years). Both experiments were conducted once a week, with each session lasting 1.5 h. Results: For both experiments, both heart rate and heart rate variability by age significantly decreased after one teaching course. Conclusions: Chan meditation practitioners benefit from receiving both face-to-face and video class teaching from a Chan master.

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An analysis of blood pressure measurement in a primary care hospital in Swaziland

African Journal of Primary Health Care & Family Medicine ◽

10.4102/phcfm.v6i1.590 ◽

2014 ◽

Vol 6 (1) ◽

Cited By ~ 3

Author(s):

Ganizani Mlawanda ◽

Michael Pather ◽

Srini Govender

Keyword(s):

Blood Pressure ◽

Blood Pressure Measurement ◽

Good Clinical Practice ◽

Clinical Decision ◽

Care Hospital ◽

Correct Treatment ◽

Primary Care Hospital ◽

The Mean ◽

The Difference ◽

The Impact

Background: Measurement of blood pressure (BP) is done poorly because of both human and machine errors.Aim: To assess the difference between BP recorded in a pragmatic way and that recorded using standard guidelines; to assess differences between wrist- and mercury sphygmomanometerbased readings; and to assess the impact on clinical decision-making.Setting: Royal Swaziland Sugar Corporation Mhlume hospital, Swaziland.Method: After obtaining consent, BP was measured in a pragmatic way by a nurse practitioner who made treatment decisions. Thereafter, patients had their BP re-assessed using standard guidelines by mercury (gold standard) and wrist sphygmomanometer.Results: The prevalence of hypertension was 25%. The mean systolic BP was 143 mmHg (pragmatic) and 133 mmHg (standard) using a mercury sphygmomanometer; and 140 mmHg for standard BP assessed using wrist device. The mean diastolic BP was 90 mmHg, 87 mmHg and 91 mmHg for pragmatic, standard mercury and wrist, respectively. Bland Altman analyses showed that pragmatic and standard BP measurements were different and could not be interchanged clinically.Treatment decisions between those based on pragmatic BP and standard BP agreed in 83.3% of cases, whilst 16.7% of participants had their treatment outcomes misclassified. A total of 19.5% of patients were started erroneously on anti-hypertensive therapy based on pragmatic BP.Conclusion: Clinicians need to revert to basic good clinical practice and measure BP more accurately in order to avoid unnecessary additional costs and morbidity associated within correct treatment resulting from disease misclassification. Contrary to existing research,wrist devices need to be used with caution.

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Who’s the boss: determining the control pathways of cardiovascular and cellular immune responses to acute stress

AJP Advances in Physiology Education ◽

10.1152/advan.00087.2017 ◽

2018 ◽

Vol 42 (2) ◽

pp. 374-379

Author(s):

Kate M. Edwards ◽

Nathan B. Morris

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Immune Cells ◽

Stress Responses ◽

Immune Cell ◽

Acute Stress ◽

Mental Arithmetic ◽

Cold Pressor ◽

Autonomic Response ◽

Blood Pressure Responses

Acute stress responses are known to include increases in heart rate and blood pressure, as well as increases in the number of circulating immune cells, all of which are governed by the autonomic nervous system. This laboratory practical measures cardiovascular and circulating immune cell responses to a passive (cold pressor) and active (mental arithmetic) acute stress task in student participants. The results allow them to examine the different patterns of autonomic response they elicit (approximated by heart rate and blood pressure responses), and knowledge of these responses can then be used to infer the governing autonomic aspect of the increases in circulating immune cells from the results. This activity can be either adapted from teacher-led methods to inquiry, asking students to design the details of the acute stress tasks, or developed by asking students to design a follow-up experiment that could be used to provide direct evidence for their conclusions. Data collected provide a platform for teaching data analysis and interpretation, as well as critical thinking.

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