Sphygmomanometric Blood Pressure Measurement Research Articles

Gestational hypertensive disorders show unique patterns of circulatory deterioration with ongoing pregnancy.

A combined assessment of heart, arteries, veins, and body fluid content throughout pregnancy has not yet been reported. We hypothesized that a gradual aggravation of circulatory dysfunction exists from the latent to the clinical phase of gestational hypertensive disease (GHD), and that pathways are unique for preeclampsia with early onset < 34 wk (EPE) and late onset ≥ 34 wk (LPE), and gestational hypertension (GH). Women with singleton pregnancy and no known diseases were invited for a prospective, observational study and had standardized sphygmomanometric blood pressure measurement, bioimpedance body water spectrum analysis, impedance cardiography for cardiac and arterial assessment, and combined Doppler-ECG of hepatic and renal interlobar veins and uterine arteries. Outcome was categorized as uncomplicated (UP, n = 1,700), EPE ( n = 87), LPE ( n = 218), or GH ( n = 188). A linear mixed model for repeated measurements, corrected for age, parity, and body mass index, was employed in SAS 9.4 to analyze trimestral changes within and between groups. From the first to the third trimester, body water increased in all groups, and an increasing number of abnormal parameters relative to UP occurred in all GHD. First-trimester blood pressure and peripheral resistance were higher in GHD than UP, together with increased uterine flow resistance and extracellular water in EPE, and with lower heart rate and aorta flow velocity in LPE. An overall gestational rise of body water volumes coexists with a gradual worsening of cardiovascular dysfunction in GHD, of which pathophysiological pathways are unique for EPE, LPE, and GH, respectively.

B4. Normal and abnormal blood pressures in early pregnancy: are we using the right cut off values?

Introduction: Subclinical hypertension has been reported in the first trimester of future hypertensive patients compared to normotensive patients. However, in clinical practice today, a cut off of 140/90 mmHg is still used to discriminate normotension from hypertension during pregnancy. We aim to investigate the most appropriate threshold for early gestational blood pressure values, which allow discriminating pregnant women between those at low or at high risk for gestational hypertensive diseases.Methods: Singleton pregnancies were included. A standard protocol was used to measure systolic (SBP), diastolic (DBP) and mean arterial pressure (MAP) in supine and standing position, by mode of an oscillometric sphygmomanometer around 12 weeks and 20 weeks of gestation. After delivery, gestational outcome was categorized in normotensive pregnancies (NP) or gestational hypertensive disease (GHD). ROC analysis was used to define the early gestational blood pressure cut off value with best possible performance in predicting GHD. Mann–Whitney U tests at nominal level a <0.05 were performed using SPSS for intergroup comparison.Results: A total of 780 women were measured at 12 weeks. Of these, 433 pregnant women were reevaluated around 20 weeks. At 12 and 20 weeks, blood pressures in GHD were higher than in NP (Table 1).Figure 1. (A) Boxplot NP versus GHD of DBP at 12 weeks, where redline indicates the threshold. (B) Boxplot UP versus GHD of DBP at 20 weeks with red line as threshold.Conclusions: Simple sphygmomanometric blood pressure measurements in standing position under standardized conditions at 12 weeks and 20 weeks has ≥96% negative predictive value for gestational hypertensive disease when DBP cut off is set at 81 and 78 mm Hg, respectively.

Pressure distribution under different types of blood pressure measurement cuffs

The principal component of any non-invasive blood pressure measurement system is an inflatable cuff. Different types of fabrics are used for inflatable cuffs construction. In this study, sphygmomanometric blood pressure measurement using inflatable cuffs was simulated in Abaqus and validated through experimental results. The purpose of the simulation is to study the effect of variation in cuff fabric geometric and mechanical properties on pressure distribution and pressure transmission during blood pressure measurement by predicting the pressure at the interface of the blood pressure cuffs and a metal cylinder. Geometric and mechanical properties of the fabrics of four different cuff types were found experimentally. Interface pressure at the cuffs and metal cylinder surface was also found experimentally using Tekscan pressure sensing system for models validation. The results of the simulation showed that the interface pressure underneath the cuffs vary with variation in geometric and mechanical properties of their fabrics. The results of the simulation were found to be in good agreement with experimental findings. This research demonstrates that the pressure distribution under the cuffs is related to the cuffs' fabric geometric and mechanical properties. This means that variation in cuffs' fabric properties could ultimately incur variations in the blood pressure values of human subjects.

English

INTRODUCTION: Rising prevalence of hypertension is a major public health challenge in India especially in Kerala. This cross sectional study was done to assess the prevalence of hypertension and its determinants in a rural population of Kottayam, Kerala. MATERIALS AND METHODS: Community based cross sectional study was carried out among 400 adults aged 30 years and above in a randomly selected ward of Ettumanoor panchayath, which is the field practice area of Govt. Medical college, Kottayam. A pretested semi structured questionnaire was used to collect information regarding socio demographic and behavioral factors. Standardized sphygmomanometric blood pressure measurement was taken by trained team members twice for each individual and the average of the two was taken as blood pressure. Anthropometric measurements were also done. A systolic blood pressure of ≥140mm of Hg and or diastolic BP≥90mm of Hg was regarded as hypertension. Data analysis was done using the software Epi-info version 3.4.3. Chi square test revealed the association between hypertension (dependent variable) and other socio demographic and behavioural factors (independent variable). A p-value of <0.05 was taken as significant. All the significant variables are included in the binary logistic regression to find out Adjusted Odds Ratio (AOR) RESULTS: The overall prevalence of hypertension was 35% (males-33.8% females -35.6%). The variables which evolved as significant and remained so in binary logistic regression analysis were single status after marriage/ unmarried (AOR-2.45 95% CI 1.38-4.38), low educational status (AOR- 2.31, 95%CI-1.46-3.64), family history of hypertension (AOR-1.85 95%CI-1.2-2.85) and trunkal obesity in females (AOR-2.41 95%CI-1.37-4.24) CONCLUSION: The present study revealed the prevalence (35%) and risk factors for hypertension in the study area. The results of the study can be used to develop messages to make the people aware of the problem of hypertension and its determinants and also the need for early diagnosis.

The effect of clothes on sphygmomanometric blood pressure measurement in hypertensive patients

To test whether there is any difference between blood pressure readings with patients wearing clothes under the manometer's cuff and not wearing clothes. The few studies published on this subject have shown that blood pressure measurements give similar results whether the patients' arm is covered by clothing or not. However, it has not been clarified whether this is also true in hypertensive patients. Blood pressure was measured on non-sleeved arm, sleeved arm and again on non-sleeved arm in 258 hypertensive patients using a mercury-filled column sphygmomanometer. Three nurses who were experienced and specially trained for the study performed blood pressure measurements. They were unaware of the purpose of the research. Measuring blood pressure with the manometer's cuff over participant's sleeved arm did not differ significantly from non-sleeved arm measurements. Sleeves have no effect on blood pressure results. Blood pressure readings taken over the sleeves will be much more practical and time saving in busy departments like emergency rooms, during disasters like earthquake where decisions have to make in minutes. Additionally, it will be time saving for general health screening surveys. Finally, it may have preferable because of hygiene concerns, patient privacy and religious beliefs.

Sphygmomanometric and ambulatory blood pressures as forerunners of carotid and femoral intima–media thickness

Studies directly comparing the associations of intima-media thickness with blood pressure (BP) on manual sphygmomanometric blood pressure measurement (SBPM) and 24-h ambulatory blood pressure measurement (ABPM) are scarce and have a cross-sectional design. At baseline, we measured systolic and diastolic blood pressures, pulse pressure, and mean arterial pressure in 532 randomly recruited patients (women, 48.3%; mean age, 38.9 years) by SBPM and ABPM. SBPM was the average of five consecutive readings obtained by trained observers at the patients' homes. We measured carotid intima-media thickness (CIMT) and femoral intima-media thickness (FIMT) by a wall-tracking ultrasound system, 26 months (median) after BP measurement (interquartile range, 21-29 months). We adjusted all analyses for observer, sex, age, BMI, smoking, and total/high-density lipoprotein-cholesterol ratio. The multivariable-adjusted associations of CIMT and FIMT with all BP components on SBPM were not significant (P >or= 0.12). In multivariable-adjusted models, CIMT increased with 24-h systolic blood pressure (effect size per SD increase, +0.131 mm; P = 0.003) and 24-h pulse pressure (+0.139 mm; P = 0.001), whereas FIMT increased with 24-h diastolic blood pressure (+0.091 mm; P = 0.03) and 24-h mean arterial pressure (+0.090 mm; P = 0.04). Models including the ambulatory blood pressure components additionally adjusted for SBPM and more covariables than those listed above were confirmatory. In a general population, BP on ABPM predicts CIMT and FIMT over and beyond highly standardized SBPM. At the elastic carotid artery, CIMT increased predominantly with the pulsatile component of BP, whereas at the muscular femoral artery, FIMT increased with the steady component of BP.

The effect of clothes on sphygmomanometric and oscillometric blood pressure measurement

Aim: We determined the effect of wearing clothes under the manometer's cuff on blood pressure in manual auscultatory sphygmomanometric and automatic oscillometric blood pressure measurement. Methods: Two hundred and one subjects were examined with the auscultatory sphygmomanometric and the automatic oscillometric method, each with and without sleeved arm in random order. The auscultatory readings were blinded for the subjects' state of clothing. Common shirts and sweaters (thinner than 2 mm) were used. Results: Based on confidence intervals of the differences between sleeved and non-sleeved arm measurements and equivalence test, sleeves did not lead to statistically significant effects. Measurements with and without sleeve can be accepted equal within an a priori defined interval of equivalence of ±4 mmHg. Discussion: This study shows that measuring blood pressure with the manometer's cuff over the subject's sleeve does not differ significantly from non-sleeved arm measurements. This is true for a sample that includes normotensive as well as hypertensive persons with a wide age range. For clinical practice, the not significant mean differences of 0.5-1.1 mmHg are interpreted as not relevant. In this study with a statistical power to find a difference of 4 mmHg, blood pressure measurements were found to be equivalent with and without clothes thinner than 2 mm.

The relationship between pulse wave velocity and pulse pressure in Chinese patients with essential hypertension.

Aortic pulse wave velocity (PWV) is a significant and independent predictor of cardiovascular disease in hypertensive subjects and in patients with end-stage renal disease, but there have been few studies on PWV in Chinese patients with essential hypertension. In this cross-sectional study, we investigated 3,156 consecutive patients (mean age: 53.7 +/- 11.58 years) of the Hypertension Division of Ruijin Hospital in Shanghai. Together with sphygmomanometric blood pressure measurements, aortic PWV was measured using a validated automatic device. PWV in patients with pulse pressure (PP) > or = 60 mmHg was significantly greater than that in patients with PP < 60 mmHg (p < 0.01). PP and PWV were positively related to age (PP: r = 0.396, p = 0.001; PWV: r = 0.531, p = 0.001). After adjustment by age and heart rate, PWV was still closely related to PP (r = 0.249, p = 0.001). At any given systolic blood pressure (SBP), PWV significantly decreased with the increase of diastolic blood pressure (DBP), whereas at any given DBP there was a significant increase of PWV with the increase of SBP. In conclusion, PWV was the major determinant of PP, and was highest in Chinese patients with isolated systolic hypertension, followed by those with systolic and diastolic hypertension, isolated diastolic hypertension, and normal blood pressure.

Aortic pulse wave velocity as a marker of cardiovascular disease in subjects over 70 years old.

Aortic pulse wave velocity (PWV) is a significant and independent predictor of cardiovascular diseases (CVD) in hypertensive subjects and in patients with end-stage renal disease, but its contribution to cardiovascular risk in subjects between 70 and 100 years old has never been tested. A cohort of 124 subjects (mean age: 87 +/- 7 years) was studied in two geriatric departments in a Paris suburb. Together with sphygmomanometric blood pressure measurements, aortic PWV was measured using a validated automatic device. Blood pressure, heart rate and body mass index, but not age, explained 48% of the PWV variability in this cohort. Furthermore, PWV was the major factor predicting the presence of CVD. The adjusted odds ratio was 17.44 (95% confidence intervals: 2.52-120.55). Antihypertensive drug therapy and low plasma albumin level had only an additive role. Blood pressure, particularly pulse pressure, had no predictive value. In 70-100-year-old subjects, aortic PWV is a strong independent marker of CVD, a finding that remains to be to confirmed by long-term longitudinal studies.

Cardiovascular reactions induced by unpredictable, predictable, and controllable painful stimuli during sphygmomanometry

Sphygmomanometry is the most common technique of blood pressure (BP) determination. In order to study effects of predictability and controllability in sphygmomanometric BP measurements, 72 normotensive healthy subjects were examined. BP was determined continuously and non-invasively using a Finapres device (Penaz-technique) and by sphygmomanometry. Five sphygmomanometric measurements took place, during the fourth the arm cuff was inflated to 300 mmHg, the others were done with a pressure of 175 mmHg. Subjects were randomly assigned to one of three groups: In one group the recordings were unpredictable to the subject, in the second group measurements were announced 1 min before cuff inflation took place, and in the third group, subjects could decide when the sphygmomanometric recordings should occur. With unpredictable measurements systolic and diastolic BP decreased (approx. 5 mmHg). When sphygmomanometric recordings were controllable or predictable to the subject BP remained relatively stable. We would suggest that automatic BP devices (e.g. in ambulatory BP monitoring) should generally work with acoustic signals, making cuff inflation predictable for the subject.

Antihypertensive Efficacy of Amlodipine

A multicentre study was conducted to investigate the effects of amlodipine on the 24-hour blood pressure profile in 153 patients with mild to moderate essential hypertension. Noninvasive ambulatory blood pressure data were collected for 24 hours before and after 24 weeks of treatment with 5 to 10mg amlodipine administered as a single morning dose. Additional antihypertensive drugs were required to achieve blood pressure control (diastolic blood pressure ≤ 90mm Hg) in 17 patients. Conventional sphygmomanometric blood pressure measurements revealed significant reductions in both systolic (24mm Hg) and diastolic (17mm Hg) blood pressure (p < 0.001 ). Ambulatory monitoring data confirmed that significant blood pressure reductions were present throughout the day, although the circadian rhythm was not altered by treatment. There were no significant effects on heart rate. Two patients (1.3%) were withdrawn because of adverse events (oedema). Significant decreases vs baseline were noted at the end of the study in total cholesterol (5.9%) and low density lipoprotein levels (7.8%).

Experience with 24-hour ambulatory blood pressure monitoring in hypertension

Traditional sphygmomanometric blood pressure measurements may lead to errors in the diagnosis of arterial hypertension due to a number of factors, among which are the alerting reaction and pressor response induced in patients by the doctor's visit. This phenomenon, as quantified in our laboratory by continuous intraarterial recordings, is responsible for an average rise in systolic and diastolic blood pressure of 27 15 mm Hg , a rise that does not seem to be reduced by simply desensitizing the patient by means of more frequent physician visits. Twenty-four hour ambulatory blood pressure monitoring may theoretically improve the diagnostic approach to hypertensive patients by overcoming some limitations of isolated cuff measurements. In recording intraarterial blood pressure in 108 ambulant hypertensive subjects, we have found that 24-hour blood pressure values are able to discriminate among patients with different degrees of target organ damage better than isolated sphygmomanometric readings. Moreover, these studies have indicated that 24-hour blood pressure variability may be as important as blood pressure mean values in the assessment of cardiovascular complications. In clinical practice, however, intraarterial blood pressure monitoring is not feasible, and only noninvasive recorders can be used. Use of these devices does not induce any alerting reaction in the patients and does not interfere with day-night blood pressure changes. Although it is characterized by intermittent readings, this approach is not incompatible with a precise estimate of 24-hour blood pressure mean values. However, the discontinuous measurements provided by the presently available noninvasive devices do not allow the precise assessment of blood pressure variability and these measurements are characterized by a considerable degree of inaccuracy when used in ambulant subjects. These limitations, combined with the lack of prospective demonstrations of the diagnostic superiority of ambulatory blood pressure monitoring over office blood pressure readings, still suggest caution in recommending a generalized use of this nevertheless promising approach to the clinical management of hypertension.

24-hour blood pressure measurements: methodological and clinical problems.

Awareness that sphygmomanometry is encompassed with serious limitations has led to the development of techniques that allow blood pressure (BP) to be monitored intraarterially or noninvasively during the day or over a 24-hour period. Although intraarterial BP monitoring allows an accurate evaluation of 24-hour BP mean and variability, its invasiveness prevents routine use in the clinical practice. This use can be more easily foreseen for noninvasive ambulatory BP monitoring, provided that the questions posed by this approach are answered. In the present study we show that the intermittent cuff inflations which allow BP to be measured noninvasively do not induce an alerting reaction and a BP rise in the patients, which means that this approach does not disrupt the daily BP profile. We also show that noninvasive BP monitoring does not alter the nocturnal hypotension, thus, preserving the day and night BP rhythm. Finally, we present evidence from a cross-sectional study that 24-hour BP monitoring reflects more closely the hypertension-related target organ damage than sphygmomanometric BP measurement and that target organ damage is related not only to average BP regimens but also to the degree of BP variability. Although support from prospective studies is necessary, this suggests that the diagnosis of hypertension and the prediction of its risk may be improved by ambulatory BP monitoring.

Does alcohol intensify the hemodynamic effects of nitroglycerin?

To evaluate the combined effects of alcohol and nitroglycerin on cardiovascular hemodynamics, M-mode echocardiography and sphygmomanometric blood pressure measurements were performed on two groups of normal subjects, before and after the administration of nitroglycerin, both in the sober state and during alcohol intoxication. In the first part of the study, 0.5 mg of nitroglycerin was given sublingually to 10 healthy volunteers 5-10 minutes after they had ingested 1 g/kg body weight of ethanol within a 30-minute period. Control experiments substituted juice for ethanol. The combined effects of ethanol and nitroglycerin on left ventricular diameters, systolic blood pressure, and wall stress were not significantly different from those of juice and nitroglycerin; heart rate and diastolic blood pressure were increased more (p less than 0.01) by ethanol and nitroglycerin. In the second part of the study, 1.0 mg of nitroglycerin was administered to a second group of 10 healthy volunteers, first in the control state and again 60 minutes after the subjects had ingested 1 g/kg body weight of ethanol within a 60-minute period. Systolic blood pressure and wall stress were significantly lower (p less than 0.01) after ethanol and nitroglycerin than after nitroglycerin before ethanol intake. We conclude that the nitroglycerin-induced reductions in left ventricular preload and afterload are not increased by alcohol during the very early phase of intoxication. However, 1 hour or more after alcohol ingestion nitroglycerin may decrease left ventricular afterload to a level significantly lower than that seen after nitroglycerin in the sober state.(ABSTRACT TRUNCATED AT 250 WORDS)