Blood Pressure Measurement Devices Research Articles

Assessment of appropriate utilization of out-of-office diagnostic tools for the diagnosis of hypertension

ABSTRACT Background: Out-of-office blood pressure (BP) measurement devices, such as ambulatory BP monitoring (ABPM) and home BP monitoring (HBPM), enhance the accuracy and reliability of BP readings, detecting white-coat and masked hypertension. The American Heart Association (AHA) advises confirming hypertension diagnoses with ABPM to prevent overdiagnosis, emphasizing the importance of precise out-of-office diagnostic tools. This study aimed to 1) explore the prevalence of ABPM and HBPM use prior to hypertension diagnosis; 2) assess the adherence to AHA recommendations regarding ABPM utilization; and 3) investigate the association between patient characteristics and out-of-office BP monitoring practices. Methods: A retrospective cross-sectional study analyzed a random sample of adult patients newly diagnosed with essential hypertension at a tertiary hospital primary care center in Riyadh, Saudi Arabia, between 2016 and 2022. Results: This study evaluated the use of ABPM and HBPM in a sample of 268 newly diagnosed hypertensive patients, with a mean age of 49.17 ± 12.69 years. Although ABPM orders were placed for 57.8% of patients, only 48.5% completed the procedure. Notably, 42.2% of hypertension diagnoses were solely based on ABPM, while 7.1% and 1.1% utilized HBPM alone or in combination with ABPM, respectively. This analysis revealed a lower utilization of ABPM among older adults, individuals with diabetes or chronic kidney disease, and married patients (P < 0.05). However, this association with marital status, diabetes, and chronic kidney disease was no longer statistically significant in a fully adjusted model (P > 0.05). Conclusion: Out-of-office BP monitoring, particularly ABPM, was underutilized in newly diagnosed hypertensive patients, especially in older age groups and patients with specific comorbidities, who may benefit the most from this method. These results underscore the need for increasing physician knowledge and compliance with the existing guidelines.

Accurate and 30-plus days reliable cuffless blood pressure measurements with 9-minutes personal photoplethysmograph data and mixed deduction learning

Cuffless blood pressure (BP) measurements have long been anticipated, and the PPG (Photoplethysmography)-only method is the most promising one since already embedded in many wearable devices. To further meet the clinical accuracy requirements, PPG-only BP predictions with personalized modeling for overcoming personal deviations have been widely studied, but all required tens to hundreds of minutes of personal PPG measurements for training. Moreover, their accurate test periods without calibration practice were not reported. In this work, we collected records of PPG data from our recruited subjects in real-life scenarios instead of relying on the openly available MIMIC dataset obtained from intensive care unit (ICU) patients. Since our objective is commercial application and a substantial reduction in training data, we tailored our model training to closely mimic real-world usage. To achieve this, we developed a training approach that only requires 9-minutes of personal PPG signal recordings and mixed with other PPG data from our recruited 364 subjects. The modeling is conducted with two-channel paired inputs to the convolutional neural network (CNN)-based model, which we called Mixed Deduction Learning (MDL). The test results of 88 samples from 15 subjects, under testing period up to 30-plus days without extra calibration, revealed that MDL meets most of the standards of AAMI, BHS, and IEEE 1708–2014 (for static test only) for BP measurement devices, which indicates MDL’s long-term stability and consistency. Furthermore, we found that the model with two-channel inputs presents a trend of improving performance as the pool of mixed training data increased, while the conventional one-channel input revealed degraded performance. The outperformance of MDL is attributed to many significant features remained in the first CNN layer even when mixing personal 9-minutes data with the other 364 subjects. Consequently, PPG-only with MDL introduces a new avenue for overcoming challenges in training due to personal physiological variations. Given our consideration of real-life usage, this technology can be seamlessly translated to commercial applications.

P066 HOW BLOOD PRESSURE DEVICES ARE OBTAINED FOR HOME BLOOD PRESSURE MEASUREMENT: A MIXED-METHODS STUDY AMONG AUSTRALIA ADULTS

Background and Objective. Only 20% of automated blood pressure (BP) devices available for purchase are validated. However, how consumers obtain devices for home BP measurement and whether their devices are validated remains unknown, which was the aim of this study. Methods. Surveys (n=225) and interviews (n=27) among adults who measure BP at home in Australia (June-December 2023). Survey questions included how the BP device was obtained, device details to determine validation status, and considerations in choosing a device. Interviews explored how and why BP devices were obtained in detail. Results. Most participants (n=216, 96%) used an upper-arm cuff device, of which 52% (n=118) were validated. Of 9 participants that used wrist cuff devices, 67% (n=6) were validated. Most participants purchased (n=176, 91%) their BP device, predominantly from pharmacy (n=126, 72%; 50% validated), followed by online (n=36, 16%; 52% validated). Validated BP devices were on average $38.53 AUD more expensive than non-validated devices (p<0.001). Although accuracy was the most important consideration when choosing a BP device (n=112, 50%), few interview participants cited device validation status as a consideration. “I just assumed that they were all accurate”. Most interview participants avoided cheaper BP devices, believing these were less accurate, and they were willing to “make an investment” in their BP device due to the importance of getting an accurate BP measurement. Interview participants rarely received recommendations from their GP about which BP device to use and reported pharmacy staff provided retail support based on in-store device availability rather than information about accuracy. Conclusion. This study found only 50% of devices used by consumers for home BP measurement have been validated. Devices that are validated are more expensive, but critically, consumers are willing to make an investment in an accurate BP device. However, little guidance is provided to support consumers when selecting a BP device. These findings demonstrate the need for credible information and resources that support consumers to obtain validated BP devices.

O30 AVAILABILITY OF PROPERLY VALIDATED AUTOMATED BLOOD PRESSURE MEASURING DEVICES FOR CHILDREN: STRIDE BP SYSTEMATIC REVIEW

Background and Objective: Properly validated automated upper-arm cuff blood pressure (BP) measuring devices are currently recommended for office, home, and ambulatory BP measurement. However, the validation of BP devices in children presents additional challenges, necessitating separate studies. This study assessed the evidence on accurate automated BP devices in children. Methods: STRIDE BP (www.stridebp.org) performs periodic systematic PubMed searches to identify validation studies of automated cuff BP monitors. Validation studies including children (3-12 years) conducted using an established protocol, including the AAMI/ESH/ISO Universal Standard (ISO 81060-2:2018), ANSI/AAMI/ISO 2013/2009, ESH-IP 2010/2002, AAMI 2002/1992/1987, and BHS 1993/1990, were identified from the STRIDE BP database. Results: Of 569 validation studies included in the STRIDE BP database, 47 (33 devices) were identified including children. Among them, STRIDE BP rejected 29 studies of which 18 were reported as “device pass” in the published paper. Among studies rejected by STRIDE BP but published as “pass”, main reasons for rejection were violations in the BP measurement procedure (sequence, number, repeats) (50%), inadequate reference device or cuffs for reference and test device (16.6%), inadequate sample size (22.2%), and single observer for reference BP (22.2%). Eventually 18 studies in children (38.3%) fulfilled all the validation protocol requirements, and 16 devices (10 available on the market) met the validation requirements and can be recommended for use in children. When additional ‘equivalent’ devices were considered (devices lacking validation studies but with differences from validated devices not affecting the measurement accuracy), 21 devices were found to be accurate, with 13 of them available on the market (Table). Conclusions: This analysis highlight a serious shortage of properly validated BP devices for children available in the market, with published validation studies often having major methodological issues. There is an urgent call to manufacturers and investigators to develop and properly validate more BP devices for children. TABLE. Validated devices for office, home, and ambulatory BP measurement in children.

O32 AVAILABILITY OF PROPERLY VALIDATED BLOOD PRESSURE MEASURING DEVICES FOR PREGNANT WOMEN: STRIDE BP SYSTEMATIC REVIEW

Background and Objective: Validated automated upper-arm cuff blood pressure (BP) measuring devices are currently recommended for BP measurement. However, a validated BP device in the general population may be inaccurate in pregnant women. Thus, separate validation studies are required in pregnant women with normal BP, hypertension, and preeclampsia. This study assessed the published evidence on BP devices in pregnancy. Methods: STRIDE BP (www.stridebp.org) performs periodic systematic PubMed searches to identify validation studies of automated cuff BP monitors. Validation studies in pregnancy conducted using an established protocol, including the AAMI/ESH/ISO Universal Standard (ISO 81060-2:2018), ANSI/AAMI/ISO 2013/2009, ESH-IP 2010/2002, AAMI 2002/1992/1987, and BHS 1993/1990, were identified. Results: Of 569 validation studies included in the STRIDE BP database, 63 (35 devices) were identified including pregnant women. Among them, STRIDE BP rejected 45 studies, of which 25 were reported as “device pass” in the published validation paper. Among the studies rejected by STRIDE BP but published as “pass”, the main reasons for rejection were violations in the BP measurement protocol (44%), inadequate reference device or cuffs for reference and test device (36%), no data in women with hypertension and/or preeclampsia (36%), single observer for reference BP measurement (28%), and inappropriate data analysis (20%). Eventually 18 studies in pregnant women (28.6%) fulfilled the protocol requirements, and 16 devices (8 of them available on the market) can be recommended for clinical use in pregnancy. When additional ‘equivalent’ devices were considered (devices lacking validation studies but with differences from validated devices not affecting the BP measurement accuracy), 37 devices were found to be accurate in pregnancy, with 27 of them available on the market (Table). Conclusions: This analysis showed a shortage of properly validated BP devices for pregnant women available in the market, with published validation often having major methodological issues. There is an urgent need to develop and properly validate more BP devices in pregnancy. TABLE. Validated devices for office, home, and ambulatory BP measurement in pregnant women.

P153 NATIONAL SURVEY OF ARGENTINE DOCTORS ON HYPERTENSION

Background and Objective: Hypertension (HTN) is the leading cardiovascular risk factor, yet its control remains low. Identifying factors influencing diagnosis, potential clinical inertia, and the measuring devices used is crucial. Objective: This study aims to understand factors in medical practice affecting HTN knowledge and control, and to assess the availability and use of blood pressure (BP) measurement devices. Methods: This observational, cross-sectional study is based on a 25-question self-administered survey by the Argentine Society of Hypertension (SAHA) and the Argentine Society of Medicine (SAM), targeting doctors treating HTN patients in Argentina. This report focuses on BP measurement. Results: A total of 1,042 responses were received, with women comprising 45.8% (n:471). Responses came from 430 cardiologists (41.7%), 380 internists (36.8%), 68 HTN specialists (6.6%), 54 primary care physicians (5.2%), and 100 from other specialties (9.7%). An own validated automatic arm BP monitor was used by 44.5%, a manual aneroid by 36.5%, an institution's validated automatic arm monitor by 10.9%, and a fixed wall aneroid by 8.2%. BP was measured in all patients by 89% of respondents, sometimes by 8.5%, and only if the patient was hypertensive by 1.7%. Ambulatory blood pressure monitoring (ABPM) was always requested before treatment by 25.2%, sporadically by 34%, never by 4.1%, and only for BP between 130/85 mmHg and 159/99 mmHg by 36.7%. The 24-hour ABPM values for initiating pharmacological treatment were >140/90 mmHg (40.9%), >135/85 mmHg (39%), and >130/80 mmHg (20.1%). Conclusions: Discrepancies exist in HTN patient care. Only 20% of doctors start pharmacological treatment at 24-hour ABPM values above 130/80 mmHg. Enhancing education and information could improve HTN control strategies.

Abstract P404: Using Target: BP™ Initiative Resources and Awards To Improve Evidence-Based Practice Adoption And Blood Pressure Control

Target: BP™ is a national initiative created by the American Heart Association and the American Medical Association in 2017 in response to the high prevalence of uncontrolled blood pressure (BP). Committed to advancing health equity, Target: BP supports health care organizations to improve blood pressure control by leveraging AHA guidelines and scientific statements and the AMA MAP ™ framework; assists health care organizations in their journeys to improve and sustain BP control with professional education and resources; and recognizes health care organizations annually with achievement awards. Target: BP recognizes organizations that commit to improvement, adopt evidence-based BP activities, and achieve BP control rates ≥70 percent, currently defined as SBP<140 and DBP<90 mmHg in CMS Controlling High Blood Pressure #236. Evidence-based BP activities include 1) calibrating BP measurement devices, 2) checking to see if devices are validated, 3) training and, 4) testing care team members in BP measurement every 6-12 months, 5) using a protocol to measure and confirm BP measurements, and 6) posting a positioning graphic (job aid) next to every place where BP is measured. Since adding evidence-based activity award criteria, self-attested achievement levels have improved from 2021 to 2023 for device calibration from 47.9% to 65.3%, for team training from 67.6% to 85.5%, for team testing from 67.0% to 86.2%, for measurement protocol use from 83.3% to 94.4%, and for job-aid posting from 54.8% to 69.6%. For each activity, Target: BP provides no-cost education and resources to help achieve the criteria. Overall participation has grown from 330 to 1806 organizations since 2017, now caring for 8.6 million patients with hypertension. In 2023, 866 organizations reported BP control rates ≥70 percent and 1489 reported the adoption of ≥4 of 6 evidence-based BP activities. Future expansion of the evidenced-based activity criteria will address treatment intensification, lifestyle risk factors, self-measured blood pressure monitoring, and equitable health outcomes. In a 2023 survey of participating organizations, 85.2% of 230 respondents reported “improving patient outcomes” as their primary reason for participating in Target: BP. Among respondents, 95.7% agree or strongly agree that expanded criteria will help to focus QI priorities. Award incentives appear to play a positive role in encouraging organizations to adopt evidence-based practices and improve blood pressure control.

May Measurement Month 2021: an analysis of blood pressure screening results from Paraguay.

The aim of this study was to highlight the importance of measuring blood pressure (BP) to identify new, known, and treated individuals with hypertension and to raise awareness in the general population about the importance of good BP control. In Paraguay, 3663 individuals aged ≥18 years of both sexes were recruited from May to November 2021 as part of the May Measurement Month (MMM) campaign, which was initiated by the International Society of Hypertension in 2017. Volunteers of 18 regional health teams applied the questionnaire provided by the MMM 2021 organization throughout the country. Due to COVID-19 constraints, the majority of the questionnaires (52.2%) were administered in health centres of the Ministry of Health and concluded with three BP and pulse readings using OMRON-automated BP measurement devices. Hypertension was defined as a systolic BP ≥ 140 mmHg or as a diastolic BP ≥ 90 mmHg or taking antihypertensive medication. We found that 57.4% of screenees were hypertensive and 72.9% of these (82.3% of women and 59.4% of men) had known hypertension. Of patients with hypertension, 70.1% were on antihypertensive medication, and 40.9% had controlled BP (<140/90 mmHg). Among hypertensives detected, 79.7% of women were on antihypertensive medication and 44.1% had controlled BP, while 56.4% of men were on treatment and 34.3% had controlled BP. In summary, we found high levels of hypertension with high rates of awareness and treatment particularly among women, although control rates were low particularly among men. This may be because most screening was conducted predominately in hospital settings.

Continuous blood pressure prediction system using Conv-LSTM network on hybrid latent features of photoplethysmogram (PPG) and electrocardiogram (ECG) signals

Continuous blood pressure (BP) monitoring is essential for managing cardiovascular disease. However, existing devices often require expert handling, highlighting the need for alternative methods to simplify the process. Researchers have developed various methods using physiological signals to address this issue. Yet, many of these methods either fall short in accuracy according to the BHS, AAMI, and IEEE standards for BP measurement devices or suffer from low computational efficiency due to the complexity of their models. To solve this problem, we developed a BP prediction system that merges extracted features of PPG and ECG from two pulses of both signals using convolutional and LSTM layers, followed by incorporating the R-to-R interval durations as additional features for predicting systolic (SBP) and diastolic (DBP) blood pressure. Our findings indicate that the prediction accuracies for SBP and DBP were 5.306 ± 7.248 mmHg with a 0.877 correlation coefficient and 3.296 ± 4.764 mmHg with a 0.918 correlation coefficient, respectively. We found that our proposed model achieved a robust performance on the MIMIC III dataset with a minimum architectural design and high-level accuracy compared to existing methods. Thus, our method not only meets the passing category for BHS, AAMI, and IEEE guidelines but also stands out as the most rapidly accurate deep-learning-based BP measurement device currently available.

The rat telemetry assay and venous catheter access buttons for use in cardiovascular safety pharmacology assessments – Surgical methods, refinements and colony maintenance

IntroductionRat telemetry is the assay of choice to assess the potential effects of novel drug candidates on cardiovascular parameters during early drug discovery. Telemetry device implantation can be combined with venous catheter and access button implantation when intravenous administration of the drug substance is required. MethodsRats (Sprague Dawley or Han Wistar) were implanted with telemetry devices for arterial blood pressure measurement using either direct aortic catheterisation (n = 131) or aortic catheterisation via the femoral artery (n = 17). Bipolar leads for ECG recording were also implanted in some of the animals (n = 102). Femoral vein catheters and access buttons were implanted as a separate surgery after the initial telemetry implantation (n = 43). Results128 animals (86%) were implanted successfully with telemetry devices without any notable surgical or post-surgical problems. When considering the 2 different catheterisation methods separately, the success rate of the direct aortic approach was 88% compared to 76% with the aortic placement via the femoral artery. Lameness was the most common post-surgical problem. Blood loss during surgery and ischaemic patches on the tail were also observed at a low incidence with the direct aortic approach. Catheter pull-out occurred in some rats before the first signal check reducing the overall success rate for blood pressure measurement using the direct aortic approach to 85%. A 95% success rate was observed for catheter and access button implantation. DiscussionA high success rate is possible when implanting telemetry devices in rats with and without venous catheters and access buttons. We have attempted to provide solutions to problems and describe refinements to the procedure which may further improve surgical outcomes.

COMPARISON OF CALIBRATION METHODS IN THE PRECISION OF A RING-TYPE CUFFLESS BLOOD PRESSURE MEASUREMENT DEVICE

Objective: This study aimed to compare the efficacy of two calibration methods for a ring-type cuffless blood pressure (BP) measurement device, CART-I Plus, to assess if regular calibration with a traditional brachial arm cuff device enhances its precision. Design and method: The study involved 40 patients, with 28 completing the study. Participants underwent calibration in three different positions (sitting, standing, supine). Prior to the initial calibration, they were seated quietly for 3–5 minutes. Calibration was executed using a conventional brachial arm cuff device on the same arm. In each position, calibration was performed twice, separated by a minimum interval of one minute. A rest period exceeding two minutes was allowed between position changes for stabilization. BP estimates from the CART-I Plus, derived from photoplethysmography signals, were then compared with corresponding conventional 24-hour ambulatory BP monitoring (ABPM) measurements. Results: The mean differences between the CART-I Plus and ABPM, when calibrated using the sitting position alone (twice), were -2.12±8.53/2.36±7.82 mmHg (awake/sleep SBP) and -4.11±7.73/0.27±7.99 mmHg (awake/sleep DBP), respectively. When calibration included all three positions (six total calibrations), the mean differences remained similar; -2.14±8.95/2.17±8.53 mmHg (awake/sleep SBP) and -4.10±7.91/0.25±7.73 mmHg (awake/sleep DBP) (p &gt; 0.5). Neither the standing nor the supine position, nor a combination of sitting and supine positions, significantly improved precision. In both standing and supine positions, the devices demonstrated a strong correlation for systolic blood pressure (SBP) (r=0.86 and r=0.90, respectively) and diastolic blood pressure (DBP) (r=0.90 for both), with all correlations being statistically significant (p &lt; 0.001). Conclusions: Provided that patient stabilization is adequately ensured, and precise brachial BP measurements are taken by medical personnel, a single sitting position calibration appears to be sufficient. The addition of dynamic three-point calibration involving standing and supine positions did not significantly enhance precision.

HOME BLOOD PRESURE MEASUREMENT IN RURAL SUB-SAHARAN AFRICA

Objective: Self-home blood pressure (BP) measurement has been reported to be superior to office BP measurements (attended or unattended) in diagnosing hypertension. However, it is not readily available in rural sub-Saharan Africa (SSA) due to the cost of the measurement devices and the literacy it requires to correctly measure and record BP. Consequently, the diagnostic performance of self-home BP measurement in rural sub-Saharan Africa remains unclear. Trained community health workers (CHWs) with home BP measurement devices may improve the availability and use of these devices by providing and training community members to use them Design and method: We are conducting a cross-sectional study to determine the diagnostic performance of self-home BP measurement in identifying individuals with hypertension in rural Kenya and The Gambia. A random age-stratified random sample of 1250 participants aged 30 years and above from the Kilifi Health and Demographic Surveillance System and the Kiang West Demographic Surveillance System are being enrolled into the study. Trained CHWs avail the measurement devices to enrolled participants and train them to measure and record their BP for seven consecutive days. Primary data of BP measurements are then downloaded from the measurement devices. Additionally, participants undergo ambulatory BP monitoring (reference standard). Results: Recruitment is ongoing. We have enrolled and completed BP measurements for 154 participants, all from the Kenya study site (12% of the total sample). Of these 106 (69%) are female with an average age of 57 years (standard deviation 15 years). Based on home and ambulatory BP respectively, 49 (32%) and 66 (43%) of included participants are hypertensive. Of the included participants, 26 (17%) have masked hypertension and were not detected by home BP while 9(6%) are normotensive but considered hypertensive based on home BP. The preliminary sensitivity and specificity of self-home BP measurement is 0.61 (0.49, 0.72) and 0.90 (0.81, 0.95) respectively while its diagnostic odds ratio (DOR) is 13.5 (likelihood ratio positive 5.93 (3.10, 11.34)). Further analyses will be conducted when recruitment is complete. Conclusions: Self-home BP measurement has modest diagnostic utility in the general population in rural SSA.

Strategies for increasing effective coverage of hypertension services in health care facilities: a scoping review

Purpose: To identify supporting and inhibiting factors for effective coverage of hypertension services, as well as recommendations for improvement efforts that can be made. Methods: A scoping review consists of five steps: Identification of research questions, identification of relevant research articles, study selection, data collection, and data synthesis. Results: 19 articles met the research objectives. Supporting factors include information systems, electronic-based pharmaceutical services, self-management, health insurance, quality improvement cycles, support for professionals, patients’ interventions, and digital technology. Inhibiting factors include low health insurance coverage, inaccurate equipment, inappropriate diagnosis and treatment, lack of screening coverage, difficulty in access, and differences in policies and procedures between regions. Recommendations for improvement include changes to service systems, the use of defined hypertension thresholds, ensuring blood pressure measurement devices are functioning properly, and the implementation of consistent policies, systems, and processes throughout the healthcare system, including between regions. Conclusion: There are various opportunities for improvement, both in utilizing existing supportive factors and reducing inhibiting factors, as well as in implementing various improvement recommendations, especially those that proved effective in published research.

Validation of the RBP-9801 oscillometric blood pressure monitor in the general population according to the association for the Advancement of Medical Instrumentation/European Society of Hypertension/ International Organization for Standardization Universal Standard.

The aim of this study was to evaluate the accuracy of the single upper-arm cuff oscillometric blood pressure (BP) monitor RBP-9801 developed for office and home BP measurement in the general population according to the Association for the Advancement of Medical Instrumentation/European Society of Hypertension/International Organization for Standardization (AAMI/ESH/ISO) Universal Standard (ISO 81060-2:2018). Subjects were recruited to fulfil the age, gender, BP and cuff distribution criteria of the AAMI/ESH/ISO Universal Standard in general population using the same arm sequential BP measurement method. A total of 105 subjects were recruited and 85 were analyzed. For validation criterion 1, the mean±SD of the differences between the test device and reference BP readings was 2.3±6.4/3.1±5.8mmHg (systolic/diastolic). For criterion 2, the SD of the mean BP differences between the test device and reference BP per subject was 5.24/5.03mmHg (systolic/diastolic). The conclusion is that the RBP-9801 oscillometric device for office and home BP measurement fulfilled all the requirements of the AAMI/ESH/ISO Universal Standard (ISO 81060-2:2018) in the general population and can be recommended for clinic and self-use at home.

Comparisons of an automated oscillometric device with a hybrid manual auscultatory device for the Korea National Health and Nutrition Examination Survey.

This study evaluated an oscillometric device (OD), Microlife WatchBP Office AFIB, and a hybrid manual auscultatory device (AD), Greenlight 300TM, to determine a suitable blood pressure (BP) measurement device for the Korea National Health and Nutrition Examination Survey in a mercury-free context. Adhering to the 2018 Universal Standard's suggested consensus, the study involved 800 subjects (mean age 51.2±17.5 years; 44.3% male), who underwent triplicate BP measurements following 5 min of rest in a randomized order (OD-first: 398 participants; AD-first: 402 participants). BP difference was calculated as OD value minus AD value, with results stratified by measurement sequence. The overall BP difference and tolerable error probability were -1.1±6.5/-2.6±4.9mmHg and 89.2%/92.5% for systolic/diastolic BP (SBP/DBP), respectively. Lin's concordance correlation coefficient was 0.907/0.844 for SBP/DBP (OD-first/AD-first: 0.925/0.892 for SBP, 0.842/0.845 for DBP). The overall agreement for hypertension (BP ≥ 140 and/or 90mmHg) was 0.71 (p<0.0001), and the OD underestimated the overall hypertension prevalence by 5.1%. Analysis of the AD-first data revealed a lower level of agreement compared to the OD-first data; however, the observed blood pressure difference adhered to Criterion 1 of the 2018 Universal Standard. Microlife met the Criterion 1 of 2018 Universal Standard but underestimated the prevalence of hypertension. The BP discrepancy increased with higher BP levels, male sex, and smaller AC. With increasing age, the discrepancy decreased for SBP and increased for DBP.

Blood Pressure Measurement Device Accuracy Evaluation: Statistical Considerations with an Implementation in R

Inaccuracies from devices for non-invasive blood pressure measurements have been well reported with clinical consequences. International standards, such as ISO 81060-2 and the seminal AAMI/ANSI SP10, define protocols and acceptance criteria for these devices. Prior to applying these standards, a sample size of N &gt;= 85 is mandatory, that is, the number of distinct subcjects used to calculate device inaccuracies. Often, it is not possible to gather such a large sample. Many studies apply these standards with a smaller sample. The objective of the paper is to introduce a methodology that broadens the method first developed by the AAMI Sphygmomanometer Committee for accepting a blood pressure measurement device. We study changes in the acceptance region for various sample sizes using the sampling distribution for proportions and introduce a methodology for estimating the exact probability of the acceptance of a device. This enables the comparison of the accuracies of existing device development techniques even if they were studied with a smaller sample size. The study is useful in assisting BP measurement device manufacturers. To assist clinicians, we present a newly developed “bpAcc” package in R to evaluate acceptance statistics for various sample sizes.

'Legacy publication of a 2009 validation of the Riester Big Ben Square Desk aneroid device for blood pressure measurement according to the European Society of Hypertension International Protocol for validation of blood pressure measuring devices in adults (2002)'.

To report a validation of the Riester Big Ben Square Desk Aneroid Sphygmomanometer according to the international protocol developed by the Working Group on Blood Pressure Monitoring of the European Society of Hypertension 2002 (ESH-IP 2002) in the interest of transparency. This legacy publication is intended to assure users that the device satisfied the requirements in place at that time. Performance of the device was assessed by participants' age, sex, arm circumference and entry SBP/DBP. Validation was performed in 33 participants. The sphygmomanometer was assessed according to the ESH-IP, which defines zones of accuracy compared to the mercury standard as ≤5, ≤10, ≤15 mmHg or more. The mean (± SD) age was 50.5 ± 13.0 years, range 29-71 years, entry SBP 142.6 ± 23.7 mmHg, entry DBP 89.0 ± 17.8 mmHg. The device passed all the requirements listed and the validation protocol. The Riester Big Ben Square Desk aneroid sphygmomanometer slightly underestimated the observer-measured SBP, yet slightly overestimated DBP. The observer-device disagreement was -0.8 ± 6.4 mmHg SBP and +0.6 ± 4.0 mmHg DBP. These data show that the Riester Big Ben Square Desk aneroid sphygmomanometer fulfilled the ESH-IP 2002 requirements for the validation of BP monitors. It was on this basis that the British and Irish Hypertension Society recommended it for clinical use in the adult population.

Comparison of Thames Medical CAT+ Doppler and SunTech Vet 20 oscillometric devices for non-invasive blood pressure measurement in conscious cats.

A comparative assessment of systolic blood pressure (BP) measurement agreement and precision in two commonly used non-invasive BP devices was carried out in conscious cats. Systolic BP measurements were obtained from 50 conscious cats as part of their clinical investigations. All measurements were taken by the same operator and were performed according to the American College of Veterinary Internal Medicine (ACVIM) consensus guidelines. The same cuff location and cuff size were used for paired measurements. The order of device use was randomised, and an arousal score was assigned during each procedure. Precision was assessed using standard deviation and coefficient of variance comparisons. Agreement was assessed using graphical and statistical comparisons of derived 'delta mean' and 'mean of means' data. A total of 50 cats aged between 3 months and 15 years were enrolled (29 domestic shorthair, seven domestic longhair, three British Shorthair, two Ragdoll, two Sphynx, two Persian, one Siamese, one Burmese, one Russian Blue, one Maine Coon and one Oriental) with a body weight in the range of 1.2-6.2 kg. BP measurements were in the range of 95-179 mmHg. Oscillometric measurements were associated with lower arousal scores. The Doppler device demonstrated superior repeatability precision. Body weight, sex, cuff size, cuff location, arousal score and the order in which the devices were used had no significant effect on precision or agreement. Correlation between the two devices was 0.0837 and agreement was considered clinically acceptable (<10 mmHg) in 32/50 (64%) cats. Of the 18 cats with suboptimal agreement, the oscillometric mean BP was higher in 14 (78%) cats. Based on this study sample, suboptimal agreement between paired CAT+ Doppler and SunTech Vet20 oscillometric BP measurements in 36% of conscious cats suggests that these devices should not be used interchangeably. Compared with Doppler, oscillometric measurements were consistently higher, particularly at higher blood pressures. Further studies are required to assess which device has superior accuracy in conscious cats.

Ability of a 24-h ambulatory cuffless blood pressure monitoring device to track blood pressure changes in clinical practice.

There is an increasing number of cuffless blood pressure (BP) measurement (BPM) devices. Despite promising results when comparing single measurements, the ability of these devices to track changes in BP levels over 24 h related to an initial calibration BP (CalibBP) is unknown. Our aim was to analyse this ability in a cuffless device using pulse transit time. We prospectively enrolled 166 participants for simultaneously performed cuffless (Somnotouch-NIBP) and cuff-based (Spacelabs 90217A/IEM Mobil-O-graph) 24 h BPM. As CalibBP for the cuffless device, first cuff-based BP was used. As surrogate for changes in BP levels after the CalibBP, we used the difference between the CalibBP and mean 24 h, awake and asleep BP measured by the two devices. In addition, we analysed the relationship between the difference of the CalibBP and the cuff-based BPM versus the difference between the cuff-based and the cuffless BPM devices. Mean(SD) difference between the CalibBP and mean 24hBP by the cuff-based or cuffless BP device were 7.4 (13.2) versus 1.8 (8.3) mmHg for systolic ( P < 0.0001) and 6.6 (6.8) versus 1.6 (5.8) mmHg for diastolic ( P < 0.0001). A near linear relationship was seen among the difference between the CalibBP and the cuff-based BPM values and the difference between the cuff-based and cuffless BPM device. Our data indicate a lower ability of the cuffless BPM device to track changes of BP levels after CalibBP. In addition, cuffless device accuracy was associated with the changes in BP levels after the initial CalibBP - the larger the BP level change, the larger the difference between the devices. https://www.clinicaltrials.gov ; Unique identifier: NCT03054688; NCT03975582.

Feasibility and Effectiveness of a Ring-Type Blood Pressure Measurement Device Compared With 24-Hour Ambulatory Blood Pressure Monitoring Device.

This study aimed to evaluate the applicability and precision of a ring-type cuffless blood pressure (BP) measurement device, CART-I Plus, compared to conventional 24-hour ambulatory BP monitoring (ABPM). Forty patients were recruited, and 33 participants were included in the final analysis. Each participant wore both CART-I Plus and ABPM devices on the same arm for approximately 24 hours. BP estimation from CART-I Plus, derived from photoplethysmography (PPG) signals, were compared with the corresponding ABPM measurements. The CART-I Plus recorded systolic blood pressure (SBP)/diastolic blood pressure (DBP) values of 131.4±14.1/81.1±12.0, 132.7±13.9/81.9±11.9, and 128.7±14.6/79.3±12.2 mmHg for 24-hour, daytime, and nighttime periods respectively, compared to ABPM values of 129.7±11.7/84.4±11.2, 131.9±11.6/86.3±11.1, and 124.5±13.6/80.0±12.2 mmHg. Mean differences in SBP/DBP between the two devices were 1.74±6.69/-3.24±6.51 mmHg, 0.75±7.44/-4.41±7.42 mmHg, and 4.15±6.15/-0.67±5.23 mmHg for 24-hour, daytime, and nighttime periods respectively. Strong correlations were also observed between the devices, with r=0.725 and r=0.750 for transitions in SBP and DBP from daytime to nighttime, respectively (both p<0.001). The CART-I Plus device, with its unique ring-type design, shows promising accuracy in BP estimation and offers a potential avenue for continuous BP monitoring in clinical practice. ClinicalTrials.gov Identifier: NCT06084065.