Development of a Cuff-Less Blood Pressure Monitoring System and Its Application.

We present an unobtrusive cuff-less sphygmomanometer based on contact-type and optical pulse sensors for continuous and minimally invasive monitoring of blood pressure (BP). We developed a cuff-less sphygmomanometer that utilizes the pulse arrival time (PAT) to estimate continuous BP. To assess its accuracy, we recruited 10 healthy subjects in whom we carried out BP studies using the cuff-less sphygmomanometer compared with a standard cuff-type device in a stationary sitting patient. Preliminary results showed that the mean difference (MD) of estimated systolic blood pressure and diastolic blood pressure were 0.96 ± 9.6 (mean ± SD) mmHg and 1.14 ± 7.5 mmHg, respectively, compared to the control. The corresponding correlation between the estimated BP values and controls were 0.78 for systolic blood pressure (p < 0.01) and 0.69 for diastolic blood pressure (p < 0.01); thus, there were significant correlations. These results suggest that the developed cuff-less sphygmomanometer has the potential for continuous BP monitoring. Finally, we conducted a preliminary study of simultaneous monitoring of cuff-less BP and near-infrared spectroscopy to evaluate the potential for assessment of autonomic nervous system functions during mental stress tasks.

Comparison of cuff-based and cuffless continuous blood pressure measurements in children and adolescents.

OBJECTIVE: In recent times, new methods of blood pressure measurements have been introduced, including cuffless blood pressure (BP) measurement device using pulse transit time (PTT) for calculation of BP values. However, it is still unknown how values obtained with a new cuffless device compare with standard ambulatory measurements in children. The main aim of the study was to investigate whether BP values measured by a cuffless PTT device are comparable with measurements by a standard upper arm cuff-based BP device. METHODS: Thirty children were prospectively included. Blood pressure measurements using the cuffless device (Somnotouch-NIBP) and cuff-based standard device (Omron 907) were performed simultaneously on the left and right arm. RESULTS: Mean systolic BP of the standard measurements was 123,47 ± 14,91 mmHg and 127,48 ± 15,98 mmHg (p < .001) measured by cuffless method. Mean diastolic BP of the standard ABPM measurements was 66,88 ± 11,86 mmHg and 68,52 ± 12,36 mmHg (p < .001). There were significant positive correlations between standard and cuffless measurements. CONCLUSION: The results show that the created PWV-BP function produces a significant correlation between BP derived from the PWV and the SBP measured by sphygmomanometry. When applying this device in clinical practice, one may keep in mind that the reported mean values over 24 hours, awake and asleep time are not directly interchangeable with cuff-based standard 24-hour BP values. The measured BP values were higher by the new technique. Although differences in SBP between both methods reached values up to 20 mmHg, we think that the development of a cuffless BP monitoring system will provide novel solutions in various medical situations.

Calibrating Local Population-Based Blood Pressure Data from NYC HANES 2013-2014.

New York City Health and Nutrition Examination Survey (NYC HANES) was a population-based cross-sectional survey of NYC adults conducted twice, in 2004 and again in 2013-2014, to monitor the health of NYC adults 20 years or older. While blood pressure was measured in both surveys, an auscultatory mercury sphygmomanometer was used to measure blood pressure in clinics in 2004, and an oscillometric LifeSource UA-789AC monitor was used in homes in 2013-2014. To assess comparability of blood pressure results across both surveys, we undertook a randomized study comparing blood pressure (BP) readings by the two devices. Blood pressure measuring protocols followed the 2013 Association for the Advancement in Medical instrumentation guidelines for non-invasive blood pressure device. Data from 167 volunteers were analyzed for this purpose.Paired t tests were used to test for significant difference in mean systolic and diastolic blood pressure between devices for overall and by mid-arm circumference categories. To test for systematic differences between the two devices, we generated Bland-Altman graphs. Sensitivity, specificity, and Kappa statistics were calculated to assess between-device agreement for high (≥ 130/80 mmHg) and not high (< 130/80 mmHg) blood pressure, with mercury set as the reference.Systolic and diastolic blood pressure measured by LifeSource UA-789AC were on average 2.0 and 1.1 mmHg higher, respectively, than those of the mercury sphygmomanometer systolic and diastolic blood pressure readings (P < 0.05). Sensitivity was 81%, specificity was 96%, and the Kappa coefficient was 75%. The Bland-Altman graphs showed that the between-device difference did not vary as a function of the average of the two devices for systolic blood pressure and was larger in the lower and upper ends for diastolic blood pressure. Given the observed differences in systolic and diastolic blood pressure readings between the two blood pressure measurement approaches, we calibrated NYC HANES 2013-2014 blood pressure data by predicting mercury blood pressure values from LifeSource blood pressure values. The mean systolic and diastolic blood pressure in NYC HANES 2013-2014 were lower when data were calibrated.

Validation of the SunTech Medical Advantage Model 2 Series Automated Blood Pressure Module in Pregnancy.

OBJECTIVE: We sought to validate the SunTech Medical Advantage Model 2 Series with firmware LX 3.40.8 algorithm noninvasive blood pressure module in a pregnant population, including those with preeclampsia. STUDY DESIGN: Validation study of an oscillometric noninvasive blood pressure module using the ANSI/AAMI ISO 81060-2:2013 standard guidelines. Pregnant women were enrolled into three subgroups: normotensive, hypertensive without proteinuria, and preeclampsia (hypertensive with random protein-to-creatinine ratio ≥ 0.3 or a 24-hour urine protein > 300 mg). Two trained research nurses, blinded to each other's measurements, used a mercury sphygmomanometer to validate the module by following the protocol set forth in the ANSI/AAMI ISO 81060-2:2013 standard guidelines. RESULTS: A total of 45 patients, 15 in each subgroup, were included. The mean systolic and diastolic differences with standard deviations between the module and the mean observers' measurements for all participants were -2.3 ± 7.3 and 0.2 ± 6.5 mm Hg, respectively. The systolic and diastolic standard deviations of the mean of the individual patient's paired module and observers' measurements were 6.27 and 5.98 mm Hg, respectively. The test device, relative to a mercury sphygmomanometer, underestimated the systolic blood pressure in patients with preeclampsia by at least 10 mm Hg in 24% (11/45) of paired measurements. CONCLUSION: The SunTech Medical Advantage Model 2 Series with firmware LX 3.40.8 algorithm noninvasive blood pressure module is validated in pregnancy, including patients with preeclampsia; however, it may underestimate systolic blood pressure measurements in patients with preeclampsia.

How well are heart rates measured by pulse oximeters and electronic sphygmomanometers? Practice-based evidence from an observational study of acutely ill medical patients during hospital admission.

BACKGROUND: heart rates generated by pulse oximeters and electronic sphygmomanometers in acutely ill patients may not be the same as those recorded by ECG. METHODS: heart rates recorded by an oximeter and an electronic sphygmomanometer were compared with electrocardiogram (ECG) heart rates measured on acutely ill medical patients. RESULTS: 1010 ECGs were performed on 217 patients while they were in the hospital. The bias between the oximeter and the ECG measured heart rate was -1.37 beats per minute (limits of agreement -22.6 to 19.9 beats per minute), and the bias between the sphygmomanometer and the ECG measured heart rate was -0.14 beats per minute (limits of agreement -22.2 to 21.9 beats per minute). Both devices failed to identify more than half the ECG recordings that awarded 3 NEWS points for heart rate. CONCLUSION: Heart rates of acutely ill patients are not reliably measured by pulse oximeter or electronic sphygmomanometers.

[Prevalence of hypertension among 18 years old and over adults in 2010-2012 in China: based on the value of mercury sphygmomanometer and converted electronic sphygmomanometer].

OBJECTIVE: To describe the age-standardized prevalence of hypertension based on the value from mercury sphygmomanometer and converted electronic sphygmomanometer among adults 18 years old and over in China 2010-2012. METHODS: Data was from the Chinese Nutrition and Health Surveillance in 2010-2012. The total number was 120 428 which selected through the method of multi-stage stratified cluster randomization sampling and probability proportion to size( PPS). The study objects were adults aged 18 and over in 31 Provinces and 150 sites in China Mainland. There were four categories areas: large cities, medium and small cities, general rural areas and poor rural areas. An average of blood pressure value was calculated though three systolic and diastolic blood pressure readings taken by mercury sphygmomanometer. The value of converted electronic sphygmomanometer was from a survey. Hypertension was defined as systolic blood pressure ≥140 mmHg and/or diastolic blood pressure ≥90 mmHg and/or use of antihypertensive drug in the past two weeks. Age-standardized result were calculated incorporating a complex sample weighting using the population data from the National Bureau of Statistics in 2009. RESULTS: The overall adjusted prevalence of hypertension based on the value of mercury sphygmomanometer among Chinese adults aged18 and over was 22. 8%( 95% CI 21. 3%-24. 3%) in 2011-2012. It was 24. 1%( 95%CI 22. 3%-26. 0%) in men and 21. 4%( 95% CI 20. 0%-22. 9%) in women. It showed 9. 7%( 95% CI 8. 6%-10. 9%), 32. 7%( 95% CI 30. 8%-34. 5%) and52. 6%( 95% CI 51. 0%-54. 3%) in 18-44, 45-59 and 60 + age groups. Hypertension was 24. 5%( 95% CI 22. 4%-26. 7%) in urban and 21. 1%( 95% CI19. 0%-23. 2%) in rural. The prevalence of hypertension based on the value of converted electronic device was 25. 2%( 95% CI 23. 6%-26. 7%). It was 26. 2%( 95%CI 24. 4%-27. 9%) in men and 24. 1%( 95% CI 22. 6%-25. 6%) in women. 10. 6%( 95% CI 9. 4%-11. 8%), 35. 7%( 95% CI 34. 0%-37. 5%) and 58. 9%( 95% CI57. 0%-60. 7%) was found in 18-44, 45-59 and 60 + age groups. Prevalent hypertension was 26. 8%( 95% CI 24. 7%-28. 8%) in urban and 23. 5%( 95% CI21. 2%-25. 8%) in rural area. CONCLUSION: Prevalence of hypertension among the adults in China is increasing. The prevalence of hypertension from mercury sphygmomanometer is lower than that of converted electronic value. Both kinds of value have similar characteristics. More men than women have a hypertension. There is a higher prevalence as growth of age. There is a decreasing prevalence of hypertension in large cities, medium and small cities, general rural areas and poor rural areas.

Validation of Omron HBP-1300 professional blood pressure monitor based on auscultation in children and adults.

UNLABELLED: BACKGROUnD: To determine whether the professional Omron HBP-1300 blood pressure (BP) monitor meets American Association for the Advancement of Medical Instrumentation (AAMI) accuracy standards in Chinese children and adults. METHOD: According to the AAMI protocol, simultaneous auscultatory measurements by two observers using a mercury manometer were obtained in participants using the Omron HBP-1300. Triple measurements were obtained after a minimum 5-min rest with a 1-min interval between adjacent measurements. RESULTS: A total of 85 participants submitted to 255 doctor-measured BP and 255 successful professional monitor readings. The initial auscultation systolic BP was <100 mmHg in 25 participants (29.4%), 100-160 mmHg in 53 participants (62.4%), and >160 mmHg in seven participants (8.2%). All of the simultaneous measurements agreed to within ± 10 mmHg, while 95% agreed to within ± 4 mmHg for both systolic and diastolic BP, and the consistency between two observers was satisfactory. The difference between the devices was -1.3 ± 3.6 mmHg for systolic BP and 0.7 ± 3.8 mmHg for diastolic BP and by AAMI method 1, which met this guideline. The average difference between two devices by AAMI method 2 was 1.4 ± 3.2 mmHg for systolic BP and 1.0 ± 3.9 mmHg for diastolic BP, which met this guideline. CONCLUSION: The professional BP monitor Omron HBP-1300 is desirable for measuring the BP for Chinese children and adults.

[Comparative study on electronic sphygmomanometer and mercury sphygmomanometer among adults in the field study].

OBJECTIVE: To compare the electronic sphygmomanometer with mercury sphygmomanometer on measuring the average blood pressure, prevalence of hypertension in a same population. To set up a numerical relationship between two blood pressure value of the two devices. METHODS: 544 adults of ≥ 18 years old were from 6 neighborhood of Hunan Province. OMRON HEM-907 and mercury sphygmomanometer were used to test the difference. The blood pressure value of mercury sphygmomanometer was gold standard. The difference of systolic pressure and diastolic pressure of two devices was tested using paired t test and Bland-Altman analysis. Chi-square test was used to analyze the two prevalence of hypertension among the same population. The equation of linear regression was established using the value of blood pressure of two devices. RESULTS: Paired t test showed the statistical difference on the systolic pressure and diastolic pressure of two devices (P < 0.0001). Chi-square test presented a higher prevalence of hypertension by using the electronic sphygmomanometer (P < 0.0001). Bland-Altman analysis showed mercury sphygmomanometer couldn't be simply replaced by electronic sphygmomanometer. The two independent equation of linear regression was calculated on systolic pressure and diastolic pressure. CONCLUSION: The difference still existed when using the electronic sphygmomanometer and mercury sphygmomanometer at a large scale population. It's important to conduct the comparative study on electronic sphygmomanometer and mercury sphygmomanometer.

[Study on blood pressure standard in children using the automatic sphygmomanometer].

In Japan, two treatment guidelines exist for pediatric patients with hypertension. The Guidelines for Drug Therapy in Pediatric Patients with Cardiovascular Diseases (JCS2012), by the Japanese Circulation Society, cite the stethoscopy-based American guidelines. The Guidelines for the Management of Hypertension (JSH2009), by the Japanese Society of Hypertension, focus on Japanese data obtained from automated sphygmomanometry. The frequent use of automated sphygmomanometers in clinical practice implies that the JSH2009 guidelines might be better; however with strict low reference values for the diastolic phase, overtreatment may result. Only the Japanese Circulation Society's guidelines include a therapeutic strategy, and the Chronic Kidney Disease (CKD) Guide, CKD Guidelines, and school urinary screening tests all cite these guidelines on stethoscopy-based blood pressure determination. Stethoscopy should be conducted during a medical examination; however, due to limited time in clinical practice, most physicians use automated sphygmomanometers while nevertheless relying on the Japanese Circulation Society reference values--which are stethoscopy-based. To find a compromise, we compared reference values in Japan with those from South Korea (automated sphygmomanometer-based) and those from the United States (stethoscopy-based). Moreover, we examined the results of recent accuracy tests for automated sphygmomanometers. Although the JSH2009 reference values for the systolic phase were consistent with those in the United States (stethoscopy-based), the reference values for the diastolic phase were lower. We observed the same tendency when comparing JSH2009 reference values with those in South Korea (automated sphygmomanometer-based). Conversely, there were only small differences between automated sphygmomanometry and mercury measurement, and we found it was possible to substitute the values from automated sphygmomanometry for stethoscopy. A large-scale study that takes into account patient height, measurement method, and treatment criteria is required to establish appropriate reference values. Even if automated sphygmomanometry is used until appropriate values are established, we consider the criteria provided in the American guidelines as appropriate.

Availability and functionality of sphygmomanometers at health care institutions in Enugu, Nigeria.

OBJECTIVE: Our aim was to investigate the availability of functional blood pressure monitors at health care institutions in Enugu, Nigeria. METHODS: During repeated surveys of 15 (primary, secondary and tertiary) health care institutions in Enugu between 2007 and 2012, records were made of the availability and functional status of sphygmomanometers in the clinics and wards. We also assessed the degree of agreement between measurements by institutional staff and measurements by trained observers using the same or the standard sphygmomanometer. RESULTS: Apart from three institutions, there was inadequate availability of fully functional sphygmomanometers: 61 staff attending to outpatients were sharing 35 sphygmomanometers, 6 of which were faulty i.e. needing repairs. Wards invariably had only one or two functional sphygmomanometers, regardless of bed occupancy. Institutional staff ignored recommended guidelines for blood pressure measurement. The overall mean difference in blood pressure measurements between institutional staff and a trained observer (1.6 mmHg; 95% confidence interval, CI: -0.3 to 3.4; P=0.1) was greater and more significant than the mean difference between the two observers (0.1 mmHg; CI: -1.5 to 1.7; P=0.9) and the mean difference between institutional and standard sphygmomanometers (-0.2 mmHg; CI: -1.7 to 1.3; P=0.8). CONCLUSION: There has been a notable lack of reporting on the availability of blood pressure measuring devices in third world health care institutions. Our surveys have shown inadequate availability of functional sphygmomanometers in the institutions, but satisfactory agreement between measurements by institutional staff and trained observers. In view of recent guidelines and recommendations, there is need to supplement office readings with mercury devices with oscillometric home or automated office blood pressure recording.

Validation of the DBP-1333b upper-arm blood pressure monitor according to the AAMI/ESH/ISO universal standard (ISO 81060-2:2018+Amd.1:2020).

To evaluate the accuracy of the DBP-1333b upper-arm blood pressure (BP) measuring device in the adult population according to the AAMI/ESH/ISO universal standard (ISO 81060-2:2018+Amd.1:2020). Subjects were recruited in the adult population. The test device was an arm-type electronic sphygmomanometer (DBP-1333b) and the reference device was a desktop sphygmomanometer (XJ11D). Using the BP data measured by the desktop sphygmomanometer as reference BP, the accuracy of the non-invasive BP module of the test device was evaluated to determine whether it met the requirements. Data from 90 individuals were analysed. According to Criterion 1, the mean difference of SBP between the test and reference device was 0.19 mmHg and the SD was 7.45 mmHg. The mean difference of DBP was -0.59 mmHg and the SD was 6.47 mmHg. The mean difference of both SBP and DBP was less than 5 mmHg, and the SD was less than 8 mmHg, which met the requirements. According to Criterion 2, SD of SBP was 5.79 mmHg, which was less than 6.95 mmHg and met the requirements. The SD of DBP was 5.58 mmHg, which was less than 6.93 mmHg and met the requirements. It was concluded that the DBP-1333b complies with the AAMI/ESH/ISO universal standard (ISO 81060-2:2018+Amd.1:2020) and can be recommended for use by the adults.

'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)'.

OBJECTIVE: 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. METHODS: 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. RESULTS: The mean (± SD) age was 50.5 ±â€…13.0 years, range 29-71 years, entry SBP 142.6 ±â€…23.7 mmHg, entry DBP 89.0 ±â€…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 ±â€…6.4 mmHg SBP and +0.6 ±â€…4.0 mmHg DBP. CONCLUSION: 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.

Predictors of muscle strength assessed with the modified sphygmomanometer test.

OBJECTIVES: To investigate the best predictor of muscle strength assessed with both Modified Sphygmomanometer Test (MST) methods (bag adaptation and non-adapted) and to provide normative values for these two MST methods for the strength assessment of the trunk, upper, and lower limb muscles. DESIGN: Cross-sectional study. METHODS: The strength of 42 muscle groups were assessed with the MST in the bag adaptation and non-adapted methods in 120 healthy individuals, 50 % males, divided into three age groups (20-39, 40-59, 60-79) with 40 subjects per group. Stepwise multiple regression analysis was performed to investigate which independent variables (sex, age, and limb dominance) is the best predictor of muscle strength (α = 5 %). RESULTS: Sex was the best independent predictor for all muscle groups for both MST methods (8.8 % < R2<57.8 %, p < 0.0001), except for the ankle plantar flexors assed with the non-adapted sphygmomanometer, in which age was the best independent predictor (R2 = 25.6 %; p < 0.0001). The normative values of muscle strength were reported for both MST methods considering the subgroups (sex, age, and limb dominance). Ceiling effect was observed when the MST bag adaptation was used to assess some muscles (8.8 %). CONCLUSION: Sex was the best predictor of muscle strength, as commonly found for muscle strength assessment with the dynamometer. The normative values provided have high clinical utility and can be used to interpret results of muscle strength assessment using both MST methods. For the MST in the bag adaptation method, caution is advised for the assessment of some muscles.

Normative value of deep neck flexors muscle strength measurement using pressure biofeedback unit and sphygmomanometer: An observational study.

PURPOSE: To find out the normative value of deep neck flexor muscles strength using pressure biofeedback unit and sphygmomanometer. METHODS: The healthy individuals both male and female aged between 18 and 25 years were recruited by stratified random sampling method from a tertiary hospital. The procedure is performed with the patient in supine lying with the neck in a neutral position. To check strength, pressure biofeedback unit and sphygmomanometer were placed under occiput and ask the individual to do the movement is genteelly and slowly as a head nodding action (chin tuck). The performance was scored via the pressure level that patient achieves 3 repetitions for 10 s hold and interval timing for 10 s. And the pressure biofeedback unit and sphygmomanometer inflated with 40 mmHg and took three reading respectively. RESULT: Our result shows, in decreased of deep neck cervical flexor muscle Strength with age group 21 (20-22) in normal adult and underweight with age group 21 (19-23) and with BMI 21 (20.1-22.4) and 16.6 (16.1-17.6) respectively. In our study, the deep neck flexor strength of overweight adults with age group 22 (21-23) and with BMI 27.8 (25.9-29.4) is stronger is than the normal and underweight adults. CONCLUSION: The study concluded that the maximal Deep neck cervical flexor strength of overweight Adults is stronger than normal and underweight Adults. The difference is maintained in all age groups. The maximal Deep neck cervical flexor strength, for flexion is developed at neutral position of neck.

Measurement of the ankle brachial index with a non-mercury sphygmomanometer in diabetic patients: a concordance study.

BACKGROUND: The removal of mercury sphygmomanometers from health centers requires the validation of other instruments to measure blood pressure in the limbs to calculate the ankle-brachial index (ABI). METHODS: Descriptive cross-sectional study of agreement between two measurement methods in type 2 diabetes patients from three urban primary healthcare centres in the Barcelonès Nord i Maresme area (Catalonia, Spain). RESULTS: 211 patients were included, from these, 421 limbs were available for study. The mean age of the participants was 67 years (SD = 10), 51.7% were women. CONCLUSION: The combination of a Doppler device with the hybrid sphygmomanometer is a simple and reliable method to measure ABI showing that hybrid sphygmomanometer is a good alternative to the use of mercury sphygmomanometers.

Estimate of nocturnal blood pressure and detection of non-dippers based on clinical or ambulatory monitoring in the inpatient setting.

BACKGROUND: Ambulatory blood pressure monitoring is regarded as the gold standard for monitoring nocturnal blood pressure (NBP) and is usually performed out of office. Currently, a novel method for monitoring NBP is indispensible in the inpatient setting. The widely used manual BP monitoring procedure has the potential to monitor NBP in the hospital setting. The feasibility and accuracy of manual sphygmomanometer to monitor NBP has not been explored widely. METHODS: A cross-sectional study was conducted at the cardiology department of a university-affiliated hospital to study patients with mild-to-moderate essential hypertension. One hundred and fifty-five patients were recruited to compare BP derived from a manual device and ambulatory BP monitoring (ABPM). The manual BP measurement was performed six times at 22:00, 02:00, 06:00, 10:00, 14:00 and 18:00 h. The measurements at 22:00, 02:00 and 06:00 h were defined as night-time and the others as daytime. ABPM was programmed to measure at 30-min intervals between measurements. RESULTS: All-day, daytime and night-time BP did not differ significantly from 24-h ambulatory systolic BP [all-day mean difference -0.52±4.67 mmHg, 95% confidence interval (CI) -1.26 to 0.22, P=0.168; daytime mean difference 0.24±5.45 mmHg, 95% CI -0.62 to 1.11, P=0.580; night-time mean difference 0.30±7.22 mmHg, 95% CI -0.84 to 1.45, P=0.601) rather than diastolic BP. There was a strong correlation between clinical and ambulatory BP for both systolic and diastolic BP. On the basis of ABPM, 101 (65%) patients were classified as non-dippers, compared with 106 (68%) by manual sphygmomanometer (P<0.001). CONCLUSIONS: Traditional manual sphygmomanometer provides similar daytime and night-time systolic BP measurements in hospital. Moreover, the detection of non-dippers by manual methods is in good agreement with 24-h ABPM. Further studies are required to confirm the clinical relevance of these findings by comparing the association of NBP in the hospital ward assessed by manual monitoring with preclinical organ damage and cardiovascular and cerebrovascular outcomes.

Neonatal blood pressure monitoring: visual assessment is an unreliable method for selecting cuff sizes.

AIM: To compare current practice of cuff size selection for noninvasive blood pressure measurement in a single-centre, tertiary-level neonatal intensive care unit (visual assessment of bladder width/limb length closest to 2/3) with common recommendations for appropriate cuff selection. METHODS: Visual assessment of the appropriate cuff size ('2/3 rule') for upper arm, forearm and calf in 103 neonates (309 cuff selections) was compared with the following recommendations: (i) Method A - guidelines of the cuff manufacturer, (ii) Method B - cuff width/limb circumference ratio 0.44-0.60 and (iii) Method C - cuff width/limb length ratio closest to 0.66. RESULTS: The upper arm cuff size was correctly chosen in 84% of cases (Method A), 43% (Method B) and 56% (Method C). The forearm cuff size was correctly chosen in 94% of cases (Method A), 68% (Method B) and 54% (Method C). The calf cuff size was correctly chosen in 96% of cases (Method A), 72% (Method B) and 63% (Method C). CONCLUSION: The accuracy of selecting cuff size by visual assessment is low. Further research on accurate cuff selection for neonates, including at the forearm and calf, is warranted.

Noninvasive studies of central aortic pressure.

Our purpose is to review noninvasive methods for measuring central arterial pressure. Indices of central arterial pressure measured from central aortic and peripheral arterial waveforms have shown value in predicting cardiovascular events and death, as well as in guiding therapeutic management. This article reviews noninvasive techniques of measuring central arterial pressure that have been validated against intra-arterial pressure. This paper explains methods to derive central (aortic and carotid) pressure from radial and brachial sites. It focuses on specific issues of brachial calibration applied to carotid pressure waveforms, which were regarded as a surrogate of aortic pressures used in three major studies (Framingham, Asklepios, and Australian National Blood Pressure 2 studies). We explain why radial-based methods are superior to carotid-based methods for estimating central pressure. Physiological principles of pressure measurement need be satisfied to ensure accurate recording.

Trends and transient change in end-digit preference in blood pressure recording: studies of sequential and longitudinal collected primary care data.

BACKGROUND: End-digit preference (EDP) is a known cause of inaccurate BP recording. Distortion has been reported around pay-for-performance (P4P) indicators. METHODS: We studied sequential datasets (n = 148,000 to n = 900,000) and performed a longitudinal analysis of CONDUIT data (n = 250,000) over a 10-year period. We examined general trends in EDP and investigated the impact of diabetes and chronic kidney disease (CKD) P4P targets. RESULTS: EDP reduces over time in both datasets; the percentage of patients with a zero EDP declined from 70% to 27% and 68% to 26% for SBP and DBP respectively. There is more zero EDP at the extremes of BP, but in people with chronic disease, the use of zero EDP was mainly seen at higher BP levels. P4P targets are associated with increased preference for the even end-digit just below target: in diabetes odds ratio (OR) is 1.47 (p = 0.003) for SBP, 1.19 (p = 0.09) for DBP and in CKD OR 1.65 (p < 0.001) for SBP and 1.48 (p = 0.0001) for DBP. Trends observed in pilot data were validated with a longitudinal set. CONCLUSIONS: The decline in EDP is levelling off and P4P targets are associated with sub-target-EDP. Primary care should automate BP measurement and recording.