Office blood pressure measurement: A comprehensive review

The conventional auscultatory methods for measuring blood pressure have been used to screen, diagnose, and manage hypertension since long. However, these have been found to be prone to errors especially the white coat phenomena which cause falsely high blood pressure readings. The Mercury sphygmomanometer and the Aneroid variety are no longer recommended by WHO for varying reasons. The Oscillometric devices are now recommended with preference for the Automated Office Blood Pressure measurement device which was found to have readings nearest to the Awake Ambulatory Blood Pressure readings. The downside for this device is the cost barrier. The alternative is to use the simple oscillometric device, which is much cheaper, with the rest and isolation criteria of the SPRINT study. This too may be difficult due to space constraints and the post‐clinic blood measurement is a new concept worth further exploration.     

Office blood pressure measurement in the 21st century

Measurement of blood pressure (BP) using the auscultatory method must follow specific rules and conditions to be reliable. Nonetheless, these requirements are often not followed in clinical practice, resulting in inaccurate BP readings. Simply replacing manual sphygmomanometers with an oscillometric device may still produce readings that are associated with a white coat effect. These limitations can be overcome by using an oscillometric sphygmomanometer that automatically records multiple readings with the patient resting quietly and alone, called automated office (AO)BP. AOBP produces office readings with a reduced white coat effect, which are also similar to the awake ambulatory BP. There is also evidence that AOBP is a better predictor of target organ damage than attended office BP. Furthermore, clinical outcome data support AOBP as having both a similar diagnostic threshold as awake ambulatory BP and a lower treatment target. Using AOBP in clinical practice simplifies recording office BP by not requiring an additional period of rest before activation of the device and by not having staff present during the actual measurements. Recent studies have reported that automatic BP measurements taken by staff in research studies with close adherence to guidelines using AOBP devices may produce similar readings to AOBP. Further research is needed to determine the best method for recording BP at systolic targets < 130 mm Hg and the relationship of office BP to ambulatory BP and home BP.     

Office and out-of-office blood pressure measurement in children and adolescents

Office and out-of-office blood pressure measurements are being used for the diagnosis of hypertension in children and adolescents. The US National Heart, Lung, and Blood Institute have recently presented a new classification of blood pressure. On the basis of office measurements the 90th, 95th and 99th percentile for gender, age and height are used to classify children and adolescents as normotensive, pre-hypertensive and stage-1 or stage-2 hypertensive. Although auscultation using a standard mercury sphygmomanometer remains the recommended method, accumulating evidence suggests that ambulatory blood pressure monitoring is useful for the detection of white-coat hypertension and the prediction of target organ damage in children and adolescents. Studies have shown ambulatory blood pressure to be more reproducible than office measurements and normative tables for ambulatory measurements have been developed from cross-sectional studies in children and adolescents. In regard to home measurements in children, there are limited data from small trials showing lower blood pressure levels than daytime ambulatory blood pressure. In conclusion, ambulatory blood pressure monitoring is already finding a role as a supplementary source of information in children and adolescents, whereas at present home measurements should not be used for decision making in this population.     

Automated blood pressure measurement in routine clinical practice

OBJECTIVE: To compare blood pressure measurements taken in routine clinical practice using an automated recorder, the BpTRU (VSM MedTech Ltd, Coquitlam, Canada), with readings taken by a conventional mercury sphygmomanometer. METHODS: Fifty consecutive patients [28 women, 22 men; mean (+/-SD) age 62+/-16 years] referred to a specialist for management of hypertension had blood pressure taken on the first visit in random order using both a mercury sphygmomanometer and an automated device. RESULTS: The mean initial automated reading (mmHg) taken with the observer present (162+/-27/85+/-12) was similar to the mean manual blood pressure taken in duplicate (163+/-23/86+12). Both values were higher (P<0.001) than the mean of the next five readings taken with the automated recorder when the patient was resting quietly alone (142+/-21/80+/-12). Women exhibited a greater fall in blood pressure with the automated device than men. CONCLUSIONS: Use of an automated blood pressure recorder can eliminate some of the white-coat effect associated with readings taken by a mercury sphygmomanometer.     

Long-term automatic blood pressure measurement in clinical management

Blood pressure control in arterial hypertension, as has been shown in randomized studies in 43,000 patients, based on a reduction of diastolic blood pressure of 5.8 mm Hg associated with a 40% reduction in stroke, is of substantial prognostic importance. Cardiac events were reduced insignificantly by 9%. Major problems with treatment are the limited acceptance of a lifelong therapy--in the Munich High Blood Pressure Study from 1982 well controlled and effective treatment was found in only 22% of the men and 16% of the women--uncertainty with regard to the indication and the question of whether the observed blood pressure elevation is situational or persistent in particular, in view of one study reporting that after three years of placebo in 48% of patients entered with diastolic values between 95 and 105 mm Hg, the blood pressure was found to lie in the normal range. Blood pressure determinations by the patients themselves may reflect resting values throughout the day but blood pressure fluctuations which can be substantial, can only be detected by ambulatory monitoring. The aim of this study, in addition to assessment of the reliability of the system employed, was to compare the response of the monitored blood pressure in patients with various stages of hypertension and in normal subjects at rest and during physical exertion to identify more accurately those in need of antihypertensive treatment. For ambulatory blood pressure monitoring, the SpaceLabs Model ICR 5200 was used. If Korotkoff sounds are not detected, the unit switches to oscillatory measuring. The storage capacity accommodates 200 measurements of systolic, diastolic and mean arterial pressure, heart rate and time of measurement.(ABSTRACT TRUNCATED AT 250 WORDS)     

Automated measurement of blood pressure in routine clinical practice

In recent years, automated devices have been developed to record blood pressure (BP) accurately in the home and during usual daily activities. Clinical outcome studies have clearly shown home BP and 24-hour ambulatory BP to be significantly better predictors of future cardiovascular events compared with BP recorded in the office setting using mercury sphygmomanometry. It is also now possible to measure office BP with the patient resting quietly alone in the examining room using an automated device. Studies in routine clinical practice using this approach have demonstrated that automated office BP can eliminate most of the white coat effect seen with manual BP measurement. The automated office BP also correlates significantly better than does the routine office BP with the 24-hour ambulatory BP, the gold standard for predicting risk of future cardiovascular events. Sufficient evidence now exists to consider incorporating automated office BP into an algorithm for diagnosing hypertension.     

Office blood pressure measurements overestimate blood pressure control in renal transplant patients

OBJECTIVE: As hypertension is an important risk factor for renal allograft failure, we aimed to assess blood pressure control in renal transplant patients with deteriorating graft function using different methods of blood pressure measurements. METHODS: Forty-nine patients with a graft survival of >1 year, and with more than a two-fold increase in urinary albumin excretion, and/or an increase in serum creatinine level >20% during the previous 12 months, were included. Office blood pressure and home BP were measured, and ambulatory blood pressures were obtained in all patients. RESULTS: The mean office blood pressure (133.2+/-16.3/81.7+/-9.6 mmHg) and 24 h ambulatory blood pressure (133.1+/-12.0/79.8+/-8.3 mmHg) were similar. Home blood pressure in the morning (144.2+/-23.3/87.1+/-12.7 mmHg) and evening (143.2+/-20.6/86.4+/-10.3 mmHg) were significantly higher than ambulatory blood pressure (P<0.001 for both). Only 18% of the patients exhibited a reduction of >or=10% in systolic blood pressure during nighttime while 39% had an overt rise. Adequate blood pressure control was found in 53% of the patients using office blood pressure (<140/90 mmHg), contrasting 29% using home blood pressure (<135/85 mmHg), and 16% using mean 24-h ambulatory blood pressure (<125/80 mmHg). These findings were substantiated by the use of receiver-operating characteristic curve analysis. CONCLUSIONS: Using the 24-h blood pressure as a standard, home blood pressure was superior to office blood pressure in estimating blood pressure control in renal transplant patients. Nocturnal hypertension, however, was observed frequently, adding important clinical information about blood pressure control in this high-risk population.     

Recent advances in blood pressure measurement technology: normalized blood pressure measurement with a double-cuff sphygmotonometer

BACKGROUND: In our previous studies of 24-h blood pressure measurement, basal blood pressure (minimum sleep-time blood pressure) showed the strongest correlation with hypertensive target-organ damage. We have currently devised a new accurate method of blood pressure measurement that entails recording casual blood pressure waves by means of a double-cuff sphygmotonometer, and attempted to normalize casual blood pressure to basal blood pressure. METHODS: The double-cuff sphygmotonometer records the arterial pressure wave, from which, using the formula (P0 = phi(-1)(i) x Pi), we attempted a normalization of casual blood pressure (Pi) to values close to those of the basal blood pressure (P0). True basal blood pressure was measured by an indirect ambulatory blood pressure monitoring device (TM2425, A&D Co. Ltd., Tokyo, Japan). The subjects were 54 normotensive volunteers and 156 out-patients with essential hypertension [63 with World Health Organization (WHO)-II stage and 93 with WHO-I stage, including 47 subjects with white-coat hypertension] not receiving medication. RESULTS: The coefficient of correlation (r) between normalized diastolic blood pressure (Pd0') and true diastolic basal blood pressure (Pd0) was 0.82 (mean difference = 1 +/- 9.8 mmHg), that between normalized systolic blood pressure (Ps0') and true systolic basal blood pressure (Ps0) being 0.78 (1 +/- 13 mmHg) in 210 subjects. When an office mean blood pressure (MBP) of 116 mmHg was taken as the standard for identifying the WHO-I group, the sensitivity was 70% (65/93) and the specificity 67% (42/63), but when an MBP0 [MBP0' = (Ps0'-Pd0')/3 + Pd0'] of 89 mmHg was the standard, the sensitivity was 82% (76/93) and the specificity 90% (57/63), both significantly higher than the corresponding values for office MBP (P < 0.05). CONCLUSION: We devised a new double-cuff sphygmotonometer and normalizing function (phi(-1)) and, using these methods, calculated the normalized blood pressure in hypertensive out-patients, which may make it possible to identify degrees of severity of hypertension in terms of WHO stages.     

Office blood pressure measurement practices among community health providers (medical and paramedical) in northern district of India

Introduction

Hypertension is directly responsible for 57% of all stroke deaths and 24% of all coronary heart disease deaths in India. Appropriate blood pressure measurement techniques are the cornerstone of clinical acumen. Despite the clear guidelines on BP measurement technique, there seems to be large inter-observer variations.

Aim & methods

A prospective, observational study was done to assess the knowledge and to study the current practices of office BP measurement among the 400 medical and paramedical staff working in various hospitals of a northern district of India. A single observer under the supervision of investigators observed all the participants and a proforma was filled based on AHA guidelines. After observing BP measurement technique scoring was done (≤8 question correct = inaccurate practices, >9 questions correct = accurate practices). Similarly, the knowledge was assessed by giving a pretested questionnaire.

Results

5.85 % of the medical staff had excellent knowledge and 80% of the doctors and 62% of the paramedical staff had good knowledge about BPM. Only 1.47% (3 doctors) and 0.5% (1 nurse) had accurate practices. There was no correlation between knowledge and practices.

Conclusions

We conclude that the right technique and knowledge of blood pressure measurement among community health providers is inadequate and warrants further interventions to improve.     

Importance of various methods of blood pressure measurement in clinical trials

Ambulatory blood pressure (ABP) monitoring and self-measurement of blood pressure (BP) are more reproducible than clinic BP measurement, minimize the white coat effect, and can reduce the sample size necessary to demonstrate the efficacy of a drug in clinical trials. For many years, the trough:peak ratio has been considered the key index for demonstrating the efficacy of antihypertensive agents. However, several potential problems are associated with the use of this index, and ABP monitoring makes it possible to examine changes in BP over the entire 24-hour period, not only at a preset time of peak effect and at the end of the dosing interval. The smoothness index provides more comprehensive information on the 24-hour BP control with treatment and avoids part of the problems encountered with the trough:peak ratio. One simple way to summarize the results of ABP monitoring in clinical trials is to provide the mean 24-hour BP difference from placebo and the BP decrease at trough. The numerous advantages summarized above make ABP monitoring an accepted method of BP measurement in hypertension therapy trials. Self-measurement of BP may be a valid and less expensive alternative to ABP monitoring.     

自动化诊室血压测量

<正>近年来,高血压领域循证研究的进展推动了各国高血压指南的更新,2017年由美国心脏病学会(American College of Cardiology,ACC)和美国心脏协会(American Heart Association,AHA)联合制定的高血压指南最具有颠覆性[1],该指南提出了高血压新定义,下调了高血压诊断界值,诊断标准前移至130/80 mmHg;且强化了降压的目标值,高血压合并明确的心血管疾病或10年动脉粥样硬化性心血管疾     

Oscillometric blood pressure measurement: progress and problems

Oscillometric blood pressure measurement has become very popular, but although a number of devices have now passed both the Association for the Advancement of Medical Instrumentation and British Hypertension Society criteria, complacency with the state of the technique is as yet premature. In individual subjects, a substantial number of readings may deviate more than a clinically relevant 5 mmHg in devices that have earned a British Hypertension Society grade A rating. The marketing of pressure-wave-simulating devices is a welcome development as monitors can now be tested for reproducibility; an intra-device standard deviation of less than 2 mmHg has been proposed as the limit. Authors suggest that these simulators are currently better suited to intra- than between-device testing since they are not yet fully confident that the simulated waveforms are indistinguishable from the man-made pressure waves. Simulators should, however, be incorporated into our standard validation protocols in order eventually to obviate the human, fallible, factor in the validation protocols. The currently employed maximal amplitude algorithm has many drawbacks as the parameter identification points for systolic and diastolic pressure depend on many factors, for example pulse pressure, heart rate and arterial stiffness. These errors have now been demonstrated in clinical studies. Modern pattern recognition algorithms are being constructed but have not yet produced convincing results. As repeatedly stated, the development of a more robust and more widely applicable algorithm than the maximal amplitude approach should be allocated a high priority.