Inverse Relationship between Cardio-Ankle Vascular Index and Body Mass Index in Healthy Children.

OBJECTIVE: To establish reference scores for cardio-ankle vascular index (CAVI), a noninvasive measure of vascular function, which reflects the stiffness of arteries, in healthy children, to test for racial and ethnic differences, and to compare CAVI scores between overweight and normal weight children. STUDY DESIGN: Subjects included 292 children aged 10-18 years: 100 non-Hispanic whites, 89 non-Hispanic blacks, and 103 Hispanics. Subjects were grouped as normal weight (body mass index [BMI] <85th percentile for age) and overweight (BMI >85th percentile for age). Blood pressure (BP) and CAVI scores were measured in all subjects. RESULTS: After controlling for age, sex, and BMI, normal weight black males had a higher CAVI score (indicating stiffer arteries) in comparison with Hispanic males and white males (5.53 ± 0.15 vs 5.13 ± 0.15 vs 5.02 ± 0.15, P = .04). BMI had an inverse association on the CAVI score (r = -0.335, P < .0001). In multivariable analysis, BMI and average CAVI scores were significant predictors of each other (R(2) = 0.37, P < .0001, R(2) = 0.21, P < .0001). There was no significant correlation between CAVI scores and resting BP values, confirming that CAVI scores were independent of concurrent BP values. CONCLUSIONS: Significant differences in vascular function exist among ethnic groups of children. Overweight children had lower CAVI scores, suggestive of vascular adaptation to obesity in early life. CAVI, by providing a noninvasive measure of vascular health, may help identify children at increased risk for cardiovascular disease.

Validation of the A&D UM-212BLE monitor according to ISO 81060-2, 2018: a device with clinically important programmability.

OBJECTIVE: The objective of this report was to describe the validation of the A&D UM-212BLE automated oscillometric sphygmomanometer to the ISO 81060-2, 2018 protocol. The device is specifically designed for enhanced office and out-of-office programmability. METHODS: A combined pediatric ( n = 35) and adult ( n = 50) population was studied at Clinmark LLC in Louisville, Colorado, USA. Same-arm sequential testing was performed following the ISO 81060-2, 2018 requirements. Five cuffs were tested with a total arm circumference range from 12 to 50 cm. Reference readings were done by two blinded observers performing simultaneous auscultation. RESULTS: For validation of Criterion 1 the mean ± SD (mmHg) of the device minus the reference differences were 3.94 ± 6.89 for SBP and 2.09 ± 6.68 for DBP. Both passed the Standard limits for Criterion 2; the systolic(S)SD achieved was 5.56 (5.70 permitted) and the diastolic(D)SD was 6.01 (6.62 permitted). All other Standard requirements were met. CONCLUSIONS: The UM-212BLE passed all requirements. The features that make this device clinically superior include settings for automated office BP, variable pressure inflation, dual measurement modes (oscillometry, auscultation), the wide range of cuffs tested, automated irregular heartbeat detection, and full validation in a pediatric population. The inclusion of all of these features makes the UM-212BLE a highly attractive device for both office and out-of-office BP estimation.

Comparison of outcomes for routine versus American Heart Association-recommended technique for blood pressure measurement (CORRECT BP): a randomised cohort study.

Background: Optimal clinical care, diagnosis and treatment requires accurate blood pressure (BP) values. The primary objective was to compare BP readings taken while adhering to American Heart Association (AHA) guidelines to those typical of routine clinical care. Specifically studied: the combined effect of feet flat on the floor, back supported, and arm supported with cuff at heart level, while adhering to other guideline recommendations. Methods: In this prospective, randomised, three-group cohort study, a modified cross-over design was applied in a primary care outpatient office setting in Columbus (OH, USA). Eligible participants were adults (aged ≥18 years) with an arm circumference of ≥18 cm and ≤42 cm who did not have a renal dialysis shunt or a previous or current diagnosis of atrial fibrillation. 150 recruited volunteers meeting the inclusion criteria were randomly randomised into the three groups. Group methodologies were BP readings taken on a fixed-height exam table followed by readings taken in an exam chair with adjustable positioning options (Group A), readings taken in the reverse order, chair then table (Group B), and both sets of readings in the exam chair (Group C). A rest period occurred before each set of readings. Group C was included for the purpose of obtaining an independent estimate of the order effect. The order in which the two types of readings (table vs chair) were taken was randomised. The primary outcome was the difference between the mean of three BP readings taken on the table and the mean of three readings taken in the chair. Findings: Between September and October, 2022, 150 participants were enrolled in the study; all 150 of whom completed testing: 48 in Group A, 49 in Group B, 53 in Group C. The mean systolic/diastolic BP (SBP/DBP) of readings taken on the table (Group A first readings, Group B second readings) were 7.0/4.5 mmHg higher than those taken in the chair (Group A second readings, Group B first readings); both statistically significant, p < 0.0001. These findings show that AHA-recommended positioning-feet flat on the floor, back supported, arm supported with the BP cuff at heart level-results in substantially lower BP values than improper positioning. The mean SBP/DBP of the first set of readings taken on the chair were 1.6/0.6 mmHg higher than for the second set of readings (Group C, included to estimate order effect). Interpretation: The observed benefit of proper positioning is sufficient to change the BP classification of several million patients from having hypertension to not having hypertension and therefore avoiding medication and/or intense follow-up. Funding: Midmark Corporation, Versailles, Ohio, USA.

Validation of the Aktiia blood pressure cuff for clinical use according to the ANSI/AAMI/ISO 81060-2:2013 protocol.

OBJECTIVE: Assess the accuracy and precision of the Aktiia initialization oscillometric upper-arm cuff device (Aktiia SA, Neuchâtel, Switzerland) for home blood pressure (BP) monitoring in the general population according to the American National Standards Institute / Association for the Advancement of Medical Instrumentation/International Organization for Standardization (ANSI/AAMI/ISO) 81060-2:2013 standard. METHODS: Three trained observers validated BP measurements performed using the Aktiia cuff versus BP measurements performed using a standard mercury sphygmomanometer. Two ISO 81060-2 criteria were used to validate the Aktiia cuff. Criterion 1 evaluated, for both SBP and DBP, whether the mean error between BP readings performed by the Aktiia cuff and auscultation was ≤±5 mmHg, and whether the SD of the error was ≤8 mmHg. Criterion 2 assessed whether, for the SBP and DBP of each individual subject, the SD of the averaged paired determinations per subject of the Aktiia cuff and of the auscultation met the criteria listed in the table of Averaged Subject Data Acceptance. RESULTS: Mean differences between the Aktiia cuff and the standard mercury sphygmomanometer (criterion 1) were 1.3 ± 7.11 mmHg for SBP and -0.2 ± 5.46 mmHg for DBP. The SD of the averaged paired differences per subject (criterion 2) was 6.55 mmHg for SBP and 5.15 mmHg for DBP. CONCLUSION: Aktiia initialization cuff complies with the requirements of the ANSI/AAMI/ISO guidelines and can be safely recommended for BP measurements in the adult population.

Statistical considerations for testing automated sphygmomanometers in special patient populations.

The International Standards Organization 81060-2:2018 is the current global Standard for the validation of automated sphygmomanometers. It specifies the requirements for clinical studies on the general population, as well as additional requirements for special populations, which might have physiologic characteristics that affect the accuracy of blood pressure measurements. This paper summarizes the statistical methodology behind the sample size required to test automated sphygmomanometers in these special populations and specifically addresses the pregnant patient population.

Contrast-enhanced sonography of malignant pediatric abdominal and pelvic solid tumors: preliminary safety and feasibility data.

BACKGROUND: Little information exists regarding pediatric contrast-enhanced US. OBJECTIVE: To assess the safety and feasibility of contrast-enhanced US of pediatric abdominal and pelvic tumors. MATERIALS AND METHODS: This prospective study included eight boys and five girls (mean age, 10.8 years) with abdominal or pelvic tumors. Cohorts of three subjects underwent US with perflutren contrast agent at escalating dose levels. Neurological and funduscopic examination, electrocardiography and continuous pulse oximetry were performed before and after contrast administration. Three radiologists independently scored six imaging parameters on pre- and postcontrast sonography. Inter-reviewer agreement was measured by the Kappa statistic. RESULTS: No neurological, retinal, electrocardiographical or pulse oximetry changes were attributable to the contrast agent. Two subjects reported minor, transient symptoms. Postcontrast US parameter scores improved slightly in 8 of 12 subjects. Postcontrast ultrasound inter-reviewer agreement improved slightly for detection of tumor margins (precontrast = 0.20, postcontrast = 0.26), local tumor invasion (precontrast = -0.01, postcontrast = 0.10) and adenopathy (precontrast = 0.35, postcontrast = 0.44). CONCLUSIONS: Although our sample size is small, perflutren contrast agents appear to be safe and well tolerated in children. Contrast-enhanced sonography of pediatric abdominal and pelvic tumors is feasible, but larger studies are needed to define their safety and efficacy in children.

Validation of the A&D UA-651 Plus/UA-651SL Plus automated sphygmomanometer according to the ISO 81060-2, 2018 and ISO 81060-2 Amendment 1, 2020, which resulted in the currently pending Amendment to Amendment 1.

In 2020 the ANSI/AAMI/ISO published Amendment 1 to the 81060-2 Standard. The purpose was to try to address issues relating to the distribution of subjects with respect to limb size ranges. It also required a new plot showing the limb circumferences on the x-axis and the device minus reference errors on the y-axis (Alpert plot). The study reported here showed inadequacies of the Amendment if significantly overlapping cuffs were to be tested. The innovative approach led to the testing of 135 subjects. Requirements for blood pressure (BP), arm circumference, and gender were fulfilled. The standard same arm sequential protocol was used. Criterion 1 calculations gave a mean ± standard deviation (SD) device minus manual BP values of 0.22 ± 7.90 mmHg for systolic BP and -0.68 ± 7.36 mmHg for diastolic BP. The maximum allowed mean value for either measurement is 5.0 mmHg. The SD values for Criterion 2 were 6.03 mmHg for systolic BP (maximum allowed 6.95) and 6.47 mmHg for diastolic BP (maximum allowed 6.90). All results passed the Standard requirements. This study demonstrated inadequacies of Amendment 1 and led to the development of an Amendment 2, still in the process of finalization. The new Amendment corrects the issues with significantly overlapping cuffs and "wide-range" cuffs. The A&D UA-651 Plus/UA-651SL Plus BP monitors and the five cuffs not only passed the requirements of 81060-2:2018 and Amendment 1 but also a revised and more rigorous protocol with more subjects involved. These devices and cuffs can be used with confidence.

Validation of the STEP deflation algorithm of the Midmark IQvitals Zone Vital Signs Monitor: part of a novel clinical ecosystem.

OBJECTIVES: Assess the accuracy of the Midmark IQvitals Zone Vital Signs Monitor STEP deflation algorithm according to the ANSI/AAMI/ISO 81060-2 Standard. METHODS: A total of 85 subjects completed the testing protocol. All standard requirements for gender, blood pressure (BP) values, and arm circumferences were met. Manual auscultation was performed by testers blinded to the device; the manual BP values were compared to the device readings. RESULTS: The Standard Criterion 1 data analyses showed mean ± SD device minus manual BP values of 1.22 ± 6.3 mmHg for SBP and -1.67 ± 6.09 mmHg for DBP. The SD values for criterion 2 were 5.06 mmHg (SBP) and 4.98 mmHg (DBP). CONCLUSIONS: The device passed all Standard requirements. The Midmark IQvitals Zone device has features to improve accuracy and reduce or eliminate transcription errors and inaccuracy from improper patient positioning.

Evaluating the impact of motion artifact on noninvasive blood pressure devices.

Most automated sphygmomanometers use oscillometric algorithms. Motion, either patient-based or environmental, will affect the ability of a device to record an accurate blood pressure (BP). Members of the Association for the Advancement of Medical Instrumentation (AAMI) Sphygmomanometer Committee have been studying this problem for more than a decade. The AAMI TIR44 was the first publication to address the challenges of motion tolerance. The concepts described in TIR44 have led to the development of a draft of ISO 81060-4, a new standard for testing devices for which the manufacturer wishes to claim motion tolerance. The current ISO 81060-2 addresses both stress testing and 24-hour ambulatory BP monitoring. Recent publications have reported on testing of devices in response to voluntary and involuntary patient motion. The ISO 81060-4 will address testing in the presence of patient transport by ground, fixed-wing, and rotary (helicopter) ambulances. The protocol will utilize noise profiles recorded under those three conditions. The profiles will be digitally stored on a library with free access. The proposed testing will be performed using patient simulators introducing the noise library files into known BP oscillometric envelopes. The specifications of the data capture and playback devices are specified, as is the evaluation statistical testing. The authors expect that the final draft will be published in 2020.

Accuracy testing of a new optical device for noninvasive estimation of systolic and diastolic blood pressure compared to intra-arterial measurements.

OBJECTIVE: The objective of this study was to compare the systolic (S) and diastolic (D) blood pressure (BP) estimations from a new optical device at the wrist with invasive measurements performed on patients scheduled for radial arterial catheterization in the ICU. Optical signals were automatically processed by a library of algorithms from Aktiia SA (OBPM - optical blood pressure monitoring algorithms). METHODS: A total of 31 participants from both sexes, aged 32-87 years, were enrolled in the study (NCT03837769). The measurement protocol consisted of the simultaneous recording of reflective photoplethysmographic signals (PPG) from the cuffless optical device and the reference BP values recorded by a contralateral radial arterial catheter. From the 31 participants, 23 subjects whose reference data quality requirements were adequate were retained for further analysis. The PPG signals from these patients were then automatically processed by the Aktiia OBPM library of algorithms, which generated uncalibrated estimates of SBP and DBP. After the automatic assessment of optical signal quality, 326 pairs of uncalibrated SBP and DBP determinations from 16 patients were available for analysis. These values were finally transformed into calibrated estimations (in mmHg) using arterial catheter SBP and DBP values, respectively. RESULTS: For SBP, a mean difference (±SD) of 0.0 ± 7.1 mmHg between the arterial catheter and the optical device values was found, with 95% limits of agreement in the Bland-Altman method of -11.9 to + 12.2 mmHg (correlation of r = 0.87, P < 0.001). For DBP, a mean difference (±SD) of 0.0 ± 2.9 mmHg between arterial catheter and the optical device values was found, with 95% limits of agreement in the Bland-Altman method of -4.8 to + 5.5 mmHg (correlation of r = 0.98, P < 0.001). CONCLUSION: SBP and DBP values obtained by radial artery catheterization and those obtained from optical measurements at the wrist were compared. The new optical technique appears to be capable of replacing more traditional methods of BP estimation.

Blood aldosterone-to-renin ratio, ambulatory blood pressure, and left ventricular mass in children.

OBJECTIVE: To assess the blood aldosterone-to-renin ratio (ARR) and its relationship to ambulatory blood pressure (ABP) and left ventricular mass (LVM) in children. STUDY DESIGN: A cross-sectional clinical study was conducted in 102 children (71.6% African American; 62.7% male) ranging in age from 7 to 18 years (mean, 13.6 years; median, 14 years). ABP (24-hour monitoring) was expressed as blood pressure index (BPI; mean blood pressure/95th percentile by sex and height). LVM was measured by echocardiography and expressed as an index (LVMI = g/height [m](2.7)). Regression analyses were used to estimate associations. RESULTS: African-American children had significantly lower serum aldosterone concentration and plasma renin activity compared with European-American children (aldosterone: 5.9 ng/dL vs 11.4 ng/dL, P < .0001; renin: 1.6 ng/mL/hour vs 2.8 ng/mL/hour, P = .01). However, ARR was not significantly different by race. ARR was not associated with 24-hour ABP but was significantly associated with LVMI (beta = 0.4 g/m(2.7); P = .02) after adjustment for the ratio of 24-hour urine Na to creatinine excretion, body mass index z- score, and ABP index. CONCLUSIONS: The data indicated a significant association between ARR and LVMI, but not ABP, in children, suggesting early cardiac remodeling associated with a high ARR.

Arterial stiffness is increased in American adolescents compared to Japanese counterparts.

Cardiovascular disease is increased in US groups versus Japanese counterparts. Increased arterial stiffness is an important predictor of cardiovascular risk. Pulse wave velocity correlates well with arterial stiffness. Gender and ethnic differences in biracial US adolescent groups have been described. No data are available evaluating differences in arterial stiffness between US and Japanese subjects. Previously published data from an adolescent (12-17 years of age) Japanese cohort were used as an historical control and were compared to an adolescent cohort from the United States. The same simple noninvasive oscillometric technique was used in each cohort to measure brachial-ankle pulse wave velocity (baPWV) as an index of arterial stiffness. The US group was a cross-sectional, biracial (64% African American, 56% female) sample of 162 subjects. The Japanese group was a cross-sectional (48% female) sample of 820 Japanese subjects. All subjects in both cohorts were normotensive (BP < 95% for gender, height, and age) adolescents (12-17 years of age). Subjects were analyzed in four groups on the basis of gender and age (12-14 and 15-17 years of age). In both individual cohorts, the mean baPWV was higher in males versus females and the baPWV increased with age. The mean baPWV was higher in all US groups versus Japanese counterparts (p < 0.0001). The mean systolic and diastolic blood pressures were higher in all Japanese groups versus US counterparts (p < 0.005). Differences in arterial stiffness are present and detectable between normotensive US and Japanese adolescent subjects. Increased arterial stiffness among these adolescent groups correlates with known adult risk for cardiovascular events among the same ethnic and gender groups.

Validation of the Welch Allyn Home blood pressure monitor with professional SureBP algorithm with a special feature of accuracy during involuntary (tremor) patient movement.

BACKGROUND: Current blood pressure (BP) measurement guidelines recommend certain patient requirements, especially keeping still for 5 min. Some patients cannot comply. My colleagues and I have reported accurate performance of the Welch Allyn SureBP algorithm for BP estimates during voluntary patient motion. No validation studies for involuntary patient movement (tremor) BP readings have been reported. This paper reports the validation of the Welch Allyn Home BP monitor, the 1700 Series, which contains that same SureBP algorithm, and the results of tremor testing as well. This device has multiple clinical advantages. PATIENTS AND METHODS: Eighty-five patients (49 females) were studied using the ANSI/AAMI/ISO 81060-2, 2013 requirements. Three sizes of cuffs were included. The tremor experiments used a simulator programmed to frequency and amplitude of oscillometric impulses typically seen in patients with diseases causing tremors. This is the first protocol developed for this clinical scenario. The device uses an inflation-based algorithm, reducing discomfort and cycle times. RESULTS: The mean±SD for the device minus manual readings per ISO Criterion 1 were -2.93±6.64 mmHg for systolic BP and -2.453±5.48 mmHg for diastolic BP. The tremor testing was performed at low, normal, and high BP simulations. The device recorded a BP value for every cycle tested. The errors (device minus manual BP estimates) were quite low. CONCLUSION: The Welch Allyn Home BP monitor is accurate in the presence of involuntary patient motion (tremor). Clinicians can have a high level of confidence in the use of a self-measurement device, which operates using the same algorithm as contained in the 'professional grade' family of devices.

Accurate blood pressure during patient arm movement: the Welch Allyn Connex Spot Monitor's SureBP algorithm.

BACKGROUND: Current blood pressure (BP) measurement guidelines specify patient requirements, including being still. Some populations of patients cannot comply. A new International Organization for Standards is being developed to test devices that claim tolerance to transport-induced motion artifacts. This study proposes the first protocol to assess BP device accuracy in the presence of patient-induced motion. PARTICIPANTS AND METHODS: Forty healthy volunteers (23 males) participated. The device tested was the Welch Allyn Connex Spot Monitor (CSM) using the SureBP algorithm. A reusable cuff was placed on the left arm. During inflation/deflation cycles the participant performed pronation/supination movements of the left forearm every 5 s. The CSM readings during motion were compared to the average of manual resting auscultatory estimations immediately before and after each motion cycle (bracketing). RESULTS: The CSM recorded a BP reading on the first cycle in 37 participants. It displayed a reading in all 40 participants with one repeat cycle in the other three. The mean±SD for the device minus the manual BP values was 0.9±7.3 mmHg for systolic BP and -3.4±7.9 mmHg for diastolic BP. CONCLUSION: This study represents a proposal for an automated BP device assessment in the presence of patient-induced motion. The CSM device, which uses an inflation-based algorithm, routinely produced BP values that closely matched auscultatory values bracketed immediately before and after the motion-associated cycle. The CSM should be of significant clinical value in populations in whom resting 'still' readings are not usually feasible, such as pediatric and geriatric patients, and patients in pain from injury or illness.

Ambulatory blood pressure and increased left ventricular mass in children at risk for hypertension.

OBJECTIVE: To relate ambulatory blood pressure (ABP) to cardiac target organ measurement in children at risk for primary hypertension (HTN). STUDY DESIGN: Left ventricular mass index (LVMI) and ABP were measured concomitantly in children (6 to 18 years) at risk for hypertension using a cross-sectional study design. RESULTS: LVMI showed a significant positive correlation with 24-hour systolic blood pressure (SBP) load, SBP index (SBPI), and standard deviation score (SDS). When subjects were stratified by LVMI percentile, there were significant differences in SBP load, 24-hour SBPI, and 24-hour SSDS. The odds ratio (OR) of having elevated LVMI increased by 54% for each incremental increase of SDS in 24-hour SSDS after controlling for race and BMI (OR = 1.54, unit = 1 SDS, CI = 1.1, 2.15, P = .011) and increased by 88% for each increase of 0.1 in BPI (OR = 1.88, CI = 1.03, 3.45, P = .04). Subjects with stage 3 HTN had significantly greater mean LVMI compared with normal subjects (P = .002 by ANOVA; LMVI, 31.6 +/- 7.9 versus 39.5 +/- 10.4). CONCLUSIONS: As systolic ABP variables increase, there is greater likelihood for increased LVMI. Staging based on ABPM allows assessment of cardiovascular risk in children with primary hypertension.

Serum uric acid and ambulatory blood pressure in children with primary hypertension.

Hyperuricemia is associated with primary hypertension (HTN) in adults and children. Furthermore, uric acid levels during childhood are associated with blood pressure (BP) levels in adulthood. We measured 24-h ambulatory BP and serum uric acid (SUA) in 104 children referred for possible hypertension. Mean age was 13.7 +/- 2.6 y (range, 7-18 y) with 67 males and 37 females; 74 were African-American, 29 Caucasian and one Asian. SUA was associated with age (r = 0.38, p = 0.0001) and BMI Z-score (r = 0.23, p = 0.021). SUA was significantly associated with mean ambulatory systolic (S) and diastolic (D) BP. Mean ambulatory BP was normalized to gender- and height-specific reference standards using BP index. SUA was significantly associated with 24-h DBP index and nocturnal DBP index after adjusting for age, gender, race, BMI Z-score and urinary sodium excretion. SUA was also significantly associated with 24-h DBP load and nocturnal DBP load. Uric acid was significantly associated with increased likelihood for diastolic HTN (OR = 2.1, CI = 1.2, 3.7; p = 0.0063) after adjusting for other co-variables. Among children at risk for HTN, the likelihood for diastolic HTN (as defined by ambulatory blood pressure monitoring) increases significantly as SUA increases. SUA may be associated with increased severity of HTN during youth.

Assessment of the validation of blood pressure monitors: a statistical reappraisal.

Protocols to determine the accuracy of noninvasive blood pressure monitors have been published by the Association for the Advancement of Medical Instrumentation, the British Hypertension Society, and the European Society of Hypertension (ESH). We compared the statistical basis for each of these protocols. Although the Association for the Advancement of Medical Instrumentation and British Hypertension Society protocols require a minimum of 85 participants, the ESH protocol requires only 33 participants. The reduced sample size results in a reduction in statistical power from 98 to 70%, which brings into question the applicability of the ESH (International) protocol.

Validation of the Welch Allyn Pro BP 2000, a professional-grade inflation-based automated sphygmomanometer with arrhythmia detection in a combined pediatric and adult population by ANSI/AAMI/ISO standard testing.

OBJECTIVE: The Welch Allyn Pro BP 2000, an automated sphygmomanometer, was subjected to ANSI/AAMI/ISO testing. PATIENTS AND METHODS: The protocol used was the same-arm sequential procedure described in the ANSI/AAMI/ISO 2013 Standard. Eight-eight (53 adults and 35 children aged 3-12 years old) patients completed testing successfully. Arm circumferences ranged from 15 to 49.5 cm. Seven different cuff sizes were used, including two long cuffs. RESULTS: All requirements for age, sex, blood pressure (BP), and cuff sizes were fulfilled. The mean±SD was -2.8±6.37 mmHg for systolic BP for criterion 1 and -3.6±6.14 mmHg for diastolic BP. The SD for criterion 2 were 5.29 for systolic BP and 5.75 for diastolic BP. All data passed the Standard's requirements. CONCLUSION: The Pro BP 2000 uses an accurate inflationary algorithm. The time for each inflation/deflation cycle is short, thus improving patient comfort. There is also arrhythmia detection to caution the use of BP values obtained during irregular heart rhythms. The algorithm for the professional-grade Pro BP 2000 is also contained in the Home BP 1700, targeted for home use. This encourages out-of-office self-measurement. The healthcare professional can be confident that the values obtained at different sites are comparable.

The Accutension Stetho, an automated auscultatory device to validate automated sphygmomanometer readings in individual patients.

The aim of this report is to describe a new device that can validate, by automated auscultation, individual blood pressure (BP) readings taken by automated sphygmomanometers.The Accutension Stetho utilizes a smartphone application in conjunction with a specially designed stethoscope that interfaces directly into the smartphone via the earphone jack. The Korotkoff sounds are recorded by the application and are analyzed by the operator on the screen of the smartphone simultaneously with the images from the sphygmomanometer screen during BP estimation. Current auscultatory validation standards require at least 85 subjects and strict statistical criteria for passage. A device that passes can make no guarantee of accuracy on individual patients. The Accutension Stetho is an inexpensive smartphone/stethoscope kit combination that estimates precise BP values by auscultation to confirm the accuracy of an automated sphygmomanometer's readings on individual patients. This should be of great value for both professional and, in certain circumstances, self-measurement BP. Patients will avoid both unnecessary treatment and errors of underestimation of BP, in which the patient requires therapy. The Stetho's software has been validated in an independent ANSI/AAMI/ISO standard study. The Stetho has been shown to perform without difficulty in multiple deflation-based devices by many manufacturers.

Accurate blood pressure measuring devices: Influencing users in the 21st century.

Hypertension is now recognized as a major global cause of morbidity and death. All decisions relating to the epidemiology, diagnosis, and management of hypertension are dependent on being able to measure blood pressure accurately. Scientists have developed protocols to assess the accuracy of blood pressure-measuring devices, but little attention has been given to informing users which devices are accurate and inaccurate. This article identifies a recipient audience of researchers, clinicians, and scientists, the public, healthcare executives and administrators, and consumer and regulatory bodies, and discusses how best to communicate the results of device accuracy to these groups with the aim of improving the accurate measurement of blood pressure.