Differences in blood pressure levels obtained by auscultatory and oscillometric methods

Levels of blood pressure measured by the conventional auscultatory method were compared with those measured by the Dinamap Monitor (Dinamap Monitor 1846 SX, Critikon Inc, Tampa, Fla), an oscillometric device. Triplicate measurements were obtained by the two methods 10 to 15 minutes apart in 381 seated fifth-grade children, ages 10 to 13 years. The width of the air bladder of the blood pressure cuff was selected to be 40% to 50% of the circumference of the upper arm. The mean systolic and diastolic pressures (at the fourth phase of Korotkoff sounds) by the auscultatory method were 6.4 mm Hg lower and 8.7 mm Hg higher than the oscillometric systolic and diastolic blood pressures, respectively. The findings of this study suggest that published normative levels of auscultatory blood pressure may be inappropriate as a standard when blood pressure measurement is obtained by the Dinamap Monitor. Until a new set of normative Dinamap blood pressure levels becomes available, one should use equations (A = 12.8 + 0.82D for systolic, and A = 34.3 + 0.54D for diastolic blood pressures at the fourth phase of Korotkoff sounds, where A is auscultatory blood pressure and D is Dinamap blood pressure) to predict auscultatory blood pressures before Dinamap blood pressures are compared with normative auscultatory blood pressure levels.     

Reliability of the Dinamap non-invasive monitor in the measurement of blood pressure of ill Asian newborns

Four hundred thirty-one paired sets of readings of systolic and diastolic blood pressure and 438 paired sets of readings of mean arterial BP from 49 ill newborns, including 21 very low birth weight infants, were analyzed for the extent and pattern of agreement and the linear relationship between the Dinamap oscillometric monitor and the direct intraarterial blood pressure readings. Agreement between the two methods was measured by the intraclass correlation, whereas the linear relationship was assessed by the product-moment correlation. The intraclass correlations for systolic, diastolic and mean blood pressures were 0.696, 0.766, and 0.781, respectively. The product-moment correlations for systolic, diastolic and mean blood pressures were 0.706, 0.768, and 0.786, respectively. BP measurements by the Dinamap monitor showed reasonably close agreement to those obtained by the intraarterial mean arterial pressure ranges above 40 mmHg. For mean arterial pressure of 40 mmHg and lower, BP readings by the Dinamap monitor tended to be higher than those obtained by the intraarterial method. These findings appeared to be consistent regardless of the birth weight of the newborn.     

Comparison of auscultatory and oscillometric blood pressures

OBJECTIVE: To study the differences in blood pressure readings between the auscultatory and oscillometric (Dinamap model 8100; Critikon, Tampa, Fla) methods. DESIGN: Survey of 2 blood pressure instruments. SETTING: Public schools. PARTICIPANTS: Seven thousand two hundred eight schoolchildren aged 5 through 17 years. MAIN OUTCOME MEASURE: Blood pressure levels. RESULTS: For all children combined, Dinamap systolic pressure readings were 10 mm Hg higher (95% confidence interval, -4 to 24 mm Hg) than the auscultatory systolic pressure readings. Dinamap diastolic pressure readings were 5 mm Hg higher (95% confidence interval, -14 to 23 mm Hg) than the auscultatory Korotkoff phase V diastolic pressure readings. CONCLUSION: These findings preclude the interchange of readings by the 2 methods. Caution must be exercised in the diagnosis of hypertension when an automated device is used.     

Accuracy of the oscillometric method to measure blood pressure in children

OBJECTIVE: The aim of this study is to analyze the substitution of the standard auscultatory method by the oscillometric blood pressure monitor, independently of the validity of the intraarterial blood pressure measurement. The accuracy of the automatic oscillometric monitor was compared to the auscultatory mercury manometer blood pressure measurement in apparently healthy school age children. METHODS: A device able to perform 3 simultaneous readings are used: one reading by the monitor and the others by two "blind" observers. We studied 72 school age children with the following characteristics: mean age 9.5 (6.1-16.1) and 39 males (54.2%). RESULTS: The difference for the systolic and diastolic blood pressure obtained by the monitor was in average + 6.2 mmHg and + 10.0 mmHg, respectively, when compared to the observer's readings. There was neither a good correlation nor a good agreement between the two observers and the monitor in the blood pressure determination. CONCLUSIONS: We concluded that the substitution of the standard auscultatory method for the non-invasive oscillometric method to measure blood pressure in school age children can not be generally recommended.     

Correlation Between Blood Pressure Measurement by Non-invasive and Invasive Methods in Critically-ill Children

Objective

To determine the correlation of non-invasive blood pressure obtained by auscultatory and oscillometric methods, with invasive blood pressure in critically ill children.

Methods

We compared invasive with auscultatory and oscillometric blood pressures using paired t-test, Pearson’s correlation coefficient and Bland-Altman plot in 50 children (age 1-12 y) admitted in Pediatric intensive care unit.

Results

Systolic, diastolic, and mean arterial pressures of invasive methods significantly correlated with auscultatory and oscillometric methods (P<0.001). Auscultatory and oscillometric measurements under-estimated systolic arterial pressures [mean (SD) difference 5.4 (12.2) mmHg and 6.3 (14.0) mmHg, respectively; P<0.001] and overestimated diastolic arterial pressures [-4.1 (5.8) mmHg and -3.6 (7.2) mmHg; P<0.001] compared to invasive blood pressure.

Conclusion

Mean arterial pressure obtained by NIBP measurement is more closer than systolic or diastolic pressures, when compared with invasive blood pressure measurement.

     

Normative arm and calf blood pressure values in the newborn

Indirect BP measurement was obtained in the right upper arm in 219 healthy newborn infants with the Dinamap monitor and was compared with values obtained from the calf to establish normative BP values and to help establish a diagnosis of hypertension and coarctation of the aorta in the newborn. There were 174 Mexican-Americans (79.5%), 33 whites (15.0%), and 12 blacks (5.5%). The width of the BP cuff was selected to be 0.4 to 0.5 times the circumference of the extremities. Three supine position readings of BPs and heart rate were obtained from each site and were averaged for statistical analyses. Mean arm BP values (+/- SD) of the neonate less than 36 hours of age were 62.6 +/- 6.9/38.9 +/- 5.7 mm Hg (48.0 +/- 6.2 mm Hg). Neonates older than 36 hours had slightly but significantly (P less than .05) greater values (4 to 6 mm Hg) than did infants younger than 36 hours of age. Active neonates had values 6 to 10 mm Hg greater than quiet neonates (P less than .05). BP values in the calf obtained with the same-sized cuff were almost identical with those obtained from the arm. Differences in consecutively obtained arm and calf BPs (arm values minus calf values) were 1.1 +/- 7.7 mm Hg systolic, -0.01 +/- 6.2 mm Hg diastolic, and 0.9 +/- 6.9 mm Hg mean pressures. Mean heart rate (+/- SD) of neonates less than 36 hours of age was 129.4 +/- 13.2 beats per minute and that of neonates older than 36 hours of age was 139.4 +/- 14.1 beats per minute.(ABSTRACT TRUNCATED AT 250 WORDS)     

The San Antonio Biethnic Children's Blood Pressure Study: auscultatory findings.

INTRODUCTION: The purpose of this study were to: (a) examine for possible ethnicity-related and gender-related differences in blood pressure (BP) in Mexican American and non-Hispanic White schoolchildren; (b) compare auscultatory and oscillometric BP levels; and (c) establish auscultatory BP standards using the width of the BP cuff based on the circumference of the arm in schoolchildren in K-12. METHODS: Participants were 6259 schoolchildren in kindergarten through 12th grade in the San Antonio, Texas, area. Auscultatory and oscillometric BP readings were obtained in random sequence, using BP cuff width 40% to 50% of the circumference of the upper arm. Averages of 3 readings were used for statistical analyses. RESULTS: Auscultatory systolic pressures (SPs) in preadolescent Mexican American boys and girls were higher (1 to 3 mm Hg) auscultatory (SP) than in their White counterparts, but the difference was clinically not important. Diastolic pressures (DP) showed no important differences. Auscultatory SPs in 13- to 18-year-old boys of both ethnic groups were significantly (P < .05) higher (3 to 12 mm Hg) than they were for girls, with no ethnic differences. Oscillometric SP was higher than auscultatory SP in children of all ages studied. Oscillometric (DP) was slightly lower (0 to 5 mm Hg) than was auscultatory K4 and higher (4 to 5 mm Hg) than was auscultatory K5 DP. DISCUSSION: No important ethnicity-related difference was found for auscultatory BP, but significant gender-related differences (boys greater than girls) were found in SP in subjects ages 13 to 18 years. Differences in BP readings by oscillometric and auscultatory methods do not allow interchange of readings. This study provides, for the first time, auscultatory BP standards using BP cuff width 40% to 50% of the arm circumference.     

Prediction of arterial blood pressure in the premature neonate using the oscillometric method

The noninvasive oscillometric measurement of blood pressure (BP) in preterm neonates has become a common practice in intensive care nurseries. The method has gained acceptance primarily through its correlation with direct arterial measurement. In this study, the oscillometric method (using Dinamap 1846) was compared with direct intra-arterial BP monitoring in 15 preterm infants. The 95% prediction intervals for individual oscillometric measurements were wide, ranging from 17 mm Hg for the mean BP to 20 mm Hg for the systolic and diastolic BP. The oscillometric method also underestimated intra-arterial systolic and mean BP and overestimated diastolic BP. Caution must be used when oscillometrically measuring BP in premature neonates.     

Assessment of Doppler ultrasound to measure systolic and diastolic blood pressures in infants and young children.

A recently developed instrument uses the Doppler shift technique to detect vessel wall movement, and it has been suggested that in conjunction with a conventional sphygmomanometer systolic and diastolic blood pressures can be measured. A controlled study was carried out in 20 children recovering from cardiac surgery where direct intra-arterial measurements (one observer) were compared with independent measurements using the Doppler instrument (2 observers). Systolic pressures measured directly and by Doppler technique correlated well and there was no significant difference between intra-arterial and indirect measurements whether the latter were taken by doctors or by nurses. In contrast, direct and indirect diastolic pressure measurements correlated poorly and were significantly overestimated with a mean difference of 6-25 mmHg (range +25 to -10) for doctors, and 4-25 mmHg (range +20 to -10) for nurses. Thus, the instrument adequately measured systolic blood pressure, but in our hands did not give precise measurements for diastolic blood pressure.     

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.     

Inhalation of nebulized nitroglycerin in dogs with experimental pulmonary hypertension induced by U46619

BACKGROUND: Pulmonary hypertension (PH) causes mortality in some congenital and acquired heart and lung diseases. However, inhalation of NO gas requires complicated and expensive instruments and elaborate preparations to avoid toxic gas administration. We tested the effectiveness and safety of inhaled nebulized nitroglycerin (Neb-NTG) in dogs with experimental PH. METHODS: Experimental PH was induced by continuous infusion of a thromboxane analog (U46619). The U46619 infusion rate was adjusted to maintain a systolic pulmonary artery pressure (PAP) at 40 mmHg in 10 anesthetized and mechanically ventilated dogs. Then, 20 micrograms/kg of NTG liquid nebulized by compressed air was inhaled. RESULTS: After infusion of U46619, the systolic, diastolic and mean PAP increased by 119%, 228% and 169%, respectively, and the systolic, diastolic and mean systemic arterial pressures (SAP) increased by 19%, 29% and 23%, respectively. The systolic pulmonary to systemic pressure ratio (Pp/Ps) and mean Pp/Ps increased by 83% and 113%, respectively, and the pulmonary vascular resistance (PVR), systemic vascular resistance (SVR) and pulmonary to systemic resistance ratio (Rp/Rs) increased by 341%, 100% and 145%, respectively. After inhalation of Neb-NTG in dogs with experimental PH, systolic, diastolic and mean PAP and PVR decreased by 25 +/- 4, 26 +/- 11, 25 +/- 9 and 31 +/- 21%, respectively. There were no significant changes in systolic, diastolic and mean SAP, SVR, cardiac output and plasma methemoglobin concentrations. The systolic and mean Pp/Ps decreased by 18 +/- 7 and 20 +/- 7%, respectively. The Rp/Rs decreased by 25 +/- 13%. CONCLUSIONS: The results of this study demonstrate that Neb-NTG is an effective and selective pulmonary vasodilator and may offer a new therapeutic option for PH.     

先天性甲状腺功能低下症对新生儿左心功能的影响

目的　评价先天性甲状腺功能低下症 (CH)新生儿的左心收缩和舒张功能变化 ,并探讨其与血甲状腺激素水平的相关性。方法　对 35例确诊为CH的新生儿和 30例正常新生儿进行超声心动图检查 ,分别用M型超声心动图测量左室射血分数 (LVEF)、左室短轴缩短率 (LVFS) ;脉冲多普勒 (PWD)测量二尖瓣口血流舒张早期峰值速度 (Em)、二尖瓣口血流舒张晚期峰值速度 (A m) ;定量组织速度成像 (QTVI)测量二尖瓣环收缩期运动峰值速度 (sm)、二尖瓣环舒张早期运动峰值速度 (em)、二尖瓣环舒张晚期运动峰值速度 (am) ;组织追踪显像 (TTI)测量收缩期二尖瓣环下移距离 (MAD) ,并对血甲状腺激素水平和心功能指标行相关性分析。结果　两组间收缩功能指标LVEF、LVFS、sm、MAD及舒张功能指标Am、Em/Am、、em/am、、Em、em 差异均有显著性意义 (P <0 0 5 ) ,其中两组间MAD、sm、Em、em 差异有极显著性意义 (P <0 0 0 1)。心脏收缩功能指标LVEF、sm、MAD及舒张功能指标Em、Am、em、em/am 与TT3 、TT4呈正相关 (P <0 0 5 ) ,与TSH呈负相关 (P <0 0 5 ) ,MAD、sm、Em、em 与血TT4、TSH水平的相关性最好 (P <0 0 0 1)。结论　先天性甲状腺功能低下症新生儿常伴有左心收缩和舒张功能下降 ,血甲状腺激素水平可直接影响左心功能 ,QTVI     

Effect of atrial natriuretic peptide on hemodynamics of the stage 21 chick embryo

Atrial natriuretic peptide (ANP) is important in the modulation of hemodynamics and fluid balance in the mature subject, but its hemodynamic effects at early stages of morphogenesis are not defined. We studied the effect of rat atriopeptin III on hemodynamics in chick embryos at Hamburger-Hamilton stage 21. The cardiovascular system is not yet innervated, nor is the kidney formed in these embryos. The vitelline arterial and venous blood pressures were measured with a servo-null, micro-pressure system and the dorsal aortic blood flow was measured with a 20 MHz pulsed Doppler velocity meter. The peptide was infused into the vitelline vein with a microinjector at doses of 0.1, 1.0, and 10 ng. Doses normalized by body wt of embryos averaged 0.003, 0.035, and 0.32 ng/mg (n = 61), respectively. Vitelline arterial blood pressure decreased in a dose dependent manner [y = 55.8 - 9.9x; r = -0.49; p less than 0.01 (y = % of baseline, x = log ng/mg)], and dorsal aortic blood flow, a measure of cardiac output, decreased similarly (y = 39.6 - 16.2x; r = -0.47; p less than 0.01). Heart rate did not change. Ten ng of ANP increased the vitelline venous diameter, determined directly under a microscope, from 125 +/- 47 (SD) microns to 139 +/- 49 microns (n = 11; p less than 0.01), and decreased vitelline venous pressure from 0.34 +/- 0.05 mm Hg to 0.10 +/- 0.07 mm Hg (n = 5). We conclude that ANP exerts its hemodynamic effect by direct venodilation in the noninnervated and anephric circulation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Carotid artery distensibility and cardiac function in adolescents with type 1 diabetes

OBJECTIVE: To determine the presence and correlates of early heart and blood vessel dysfunction in adolescents with type 1 diabetes mellitus (DM) of relatively short duration. STUDY DESIGN: A total of 33 patients with DM (20 male, mean age 15.8 +/- 1.3 years, mean DM duration 9.3 +/- 3.9 years) and 16 healthy subjects in a nondiabetic control group (7 male, mean age 17.4 +/- 1.7 years) underwent (1) ultrasonography of the right carotid artery to assess distensibility, compliance, and intimal-medial thickness (IMT), (2) echocardiographic assessment of systolic and diastolic ventricular function, (3) lipid profile and hemoglobin A(1c), and (4) overnight timed urine collections for albumin excretion rate. RESULTS: Ultrasonography showed significantly lower carotid artery distensibility in the DM group (38.5 +/- 8.2 x 10(-3) vs 46.5 +/- 11.7 x 10(-3)/kPa, P =.01) but no difference in compliance (14.0 +/- 3.4 x 10(-7) vs 15.8 +/- 2.9 x 10(-7)m(2)/kPa, P =.08) or IMT (0.061 +/- 0.013 vs 0.060 +/- 0.014 cm, P =.77). Left ventricular (LV) end-diastolic diameter, LV posterior wall thickness, end-systolic wall stress, shortening fraction, ejection fraction, LV mass, and diastolic function were similar in both groups. Total cholesterol, low density lipoprotein, high density lipoprotein, triglycerides, and blood pressure were also similar. The median albumin excretion rate was 4.8 microg/min in the DM group (range 1.1 to 19.2) and 3.0 microg/min in the control group (range 1.4 to 5.8) (P =.03). Hemoglobin A(1c) correlated inversely with both distensibility (r = -.43, P =.02) and compliance (r = -.39, P =.032). CONCLUSIONS: This study indicates that early changes in macrovascular function, namely lower carotid artery distensibility, may precede abnormalities in cardiac function or in arterial IMT in adolescents with short duration type 1 DM. It also supports a relationship between hyperglycemia and carotid artery dysfunction.     

Comparison of Dinamap 8100 with sphygmomanometer blood pressure measurement in a prepubertal diabetes cohort

OBJECTIVE: To compare the conventional sphygmomanometer with the semiautomated Dinamap 8100 (Critikon, Tampa, FL, USA) for the measurement of blood pressure in prepubertal children with insulin-dependent diabetes mellitus. METHODOLOGY: Blood pressure was measured using both methods in 61 prepubertal children (aged 8-13 years) on 189 occasions over 4 years. The measurements were compared using the Bland-Altman plot. Tracking correlations of blood pressure centiles over time were analyzed by the general estimating equation. RESULTS: Accuracy criteria of the Association for the Advancement of Medical Instrumentation were met and a British Hypertensive Society 'B' grading was reached. Differences in systolic and diastolic blood pressure were found between the two methods (P < 0.01). For systolic blood pressure, common correlations were 0.54 (Dinamap) and 0.51 (sphygmomanometer) and for diastolic blood pressure were 0.33 and 0.42, respectively. CONCLUSION: The Dinamap 8100 is an acceptable alternative in clinic practice and research for prepubertal children.     

Intermediate-term follow-up results of pulmonary balloon valvuloplasty in children

Twenty-two patients (10 boys, 12 girls) with pulmonary valve stenosis whose mean age was 6.7 +/- 4.1 years (range 1 to 14 years) at time of the procedure underwent balloon dilatation angioplasty. All patients had isolated pulmonary valve stenosis with no associated cardiac anomalies, and their pulmonary valvular gradients were greater than 50 mmHg. Diagnostic catheterization and balloon valvuloplasty were performed during the same procedure. The mean peak systolic pressure gradient before balloon dilation of 95.8 +/- 29.5 mmHg (54-163 mmHg) was reduced to 30.2 +/- 15.8 mmHg (7-64 mmHg) after balloon dilation (p < 0.001). A linear relation was found between the predilation pressure gradient and the pressure gradient drop (r = 0,86; SE: 28.94) (y = 0.89x - 12.11). Following a successful valvuloplasty, the mean peak systolic pressure in the right ventricle decreased from 119.0 +/- 30.4 mmHg (71-184 mmHg) to 55.2 +/- 16.9 mmHg (29-97 mmHg) (p < 0.001). Continuous wave Doppler was used for follow-up. Pressure gradients were estimated in 14 patients between one and 29 months after the dilation 120 +/- 7.1 months). The mean follow-up gradient was 19.0 +/- 6.0 mmHg (11-32 mmHg). No important complication was noted in the immediate course or throughout the follow-up period, but four patients (28.6%) had minimal pulmonary insufficiency. In conclusion, these data confirm that balloon dilation in valvular pulmonary stenosis is safe and effective, and suggest that stenosis does not recur.     

Oscillometric Blood Pressure Standards for Children

We previously reported blood pressure (BP) readings obtained by the Dinamap (DIN) (Model 8100) were 10 mmHg higher than those obtained by auscultatory methods and thus were not interchangeable. DIN BP data on 7208 schoolchildren ages 5 to 17 were analyzed to generate normative DIN BP standards and to examine the rational for presenting BP standards according to age and height percentiles. Three BP measurements were taken in the sitting position using a BP cuff width 40% to 50% of the circumference of the arm. Boys’ systolic pressures (SP) were significantly (p < 0.05) greater (up to 11 mmHg) than those of the girls in subjects age 13 to 17 years. SP levels were most closely correlated with weight (r = 0.595), followed by height (r = 0.560) and age (r = 0.518). When BP levels were adjusted for age and weight, the correlation coefficient of DIN SP with height was negligible (r = 0.026 for boys; r = 0.085 for girls), whereas when adjusted for age and height, the correlation of SP with weight remained high (r = 0.303 for boys; r = 0.216 for girls), indicating that height is not an important independent predictor of BP levels. In conclusion, Dinamap-specific BP standards presented in this report are the only standards that have been generated according to the current BP guidelines recommended by national committees. We found no rational for presenting BP standards according to age and height percentiles.     

Continuous non-invasive finger blood pressure monitoring in children

Tanaka H, Thulesius O, Yamaguchi H, Mino M, Konishi K. Continuous non-invasive finger blood pressure monitoring in children. Acta Padiatr 1994;83:646–52. Stockholm. ISSN 0803–5253
We evaluated the performance of continuous non-invasive finger arterial pressure measurement using the volume-clamp technique (Finapres). The study was designed to compare finger arterial pressure with brachial blood pressure estimated by the auscultatory method in 217 children (90 boys and 127 girls) aged 4–16 years and in 38 adults (aged 18–45 years). Finger and brachial artery pressure readings were obtained consecutively from the ipsilateral side in the supine position. Fingcr arterial pressure waveforms were recorded in all children except 4 with small and thin fingers. There was good agreement for systolic pressure with only a slight underestimation of 1.9 mmHg and 5.1 mmHg lower for diastolic pressure. This difference most probably reflects inaccuracy of the auscultatory cuff method rather than an error in the Finapres. There was large inter-individual variability in Finapres recordings which might be due to diffcrences in vasomotor tone, as demonstrated by systolic amplification in 5 patients with anorexia. However, Finapres showed a small within-subject variability (3.8 mmHg for systolic and 4.1 mmHg for diastolic pressure) dctermined in 5 patients during phenylephrine infusion, and as good reproducibility as the auscultatory method. These results suggest that finger arterial pressure measurement in children older than 6 years of age has similar accuracy as that in adults, and that this method is useful for clinical applications in children, especially for the non-invasive evaluation of autonomic control and cardiovascular reflexes involving transient and rapid blood pressure changes.     

Random-zero sphygmomanometer, Rose's tape, and the accuracy of the blood pressure measurements in children.

In the Cardiovascular Risk in Young Finns project, blood pressure (BP) was measured in 3549 randomly selected children aged 6-18 y in 1980, and 2887 and 2500 of the same individuals in 1983 and 1986, respectively. An ordinary mercury sphygmomanometer (OMS) was used in the first two surveys and a random-zero sphygmomanometer (RZS) in the third survey. Systolic and diastolic BP were lower when measured with an RZS than with an OMS and the shape of the age-related BP curve obtained with an RZS was significantly different from that obtained with an OMS, because low BP values were apparently measured more accurately with the former. Use of the RZS did not affect the distribution of the BP values. Rose's tape readings were used to evaluate the effect of training and to control the accuracy of the BP measurements. According to Rose's tape readings, Korotkoff's 4th phase BP was more difficult to measure accurately than 5th phase (p = 0.002). The mean values for the differences between the correct and actual BP readings on the Rose's tape were -1.2 mm Hg (SD 2.1) for systolic BP, 8.3 mm Hg (SD 13.6) for diastolic Korotkoff's 4th phase BP, and 1.2 mm Hg (SD 7.0) for diastolic Korotkoff's 5th phase BP, with a negative value indicating that the BP phase was measured lower than the correct value. Terminal digit preference was present in each survey to such an extent that it could have hampered the reaching of reliable conclusions from the data obtained with an OMS. The bias caused by terminal digit preference was obviated by the RZS.(ABSTRACT TRUNCATED AT 250 WORDS)     

Doppler ultrasonic brachial blood pressure measurements in normal Chinese neonates: a preliminary report

The purpose of this study was to determine brachial blood pressures in normal Chinese neonates using a Doppler ultrasonic blood pressure monitor (Roche Arteriosonde 1020). The systolic (SP) and diastolic (DP) pressures of 100 healthy, full-term Chinese neonates were determined in triplicate under resting conditions. The pulse pressures (PP) were derived from the SP and DP. Correlation studies reveal significant positive correlation between age and PP (r = 0.34, P less than 0.0002), between weight and SP (r = 0.23, P less than 0.02) and between weight and PP (r = 0.40, P less than 0.02). No significant difference exists between blood pressures of males and females (P greater than 0.05). Comparison with three Western studies reveals that our mean SP is the lowest (1-3). This may be due to technical factors, e.g. different Doppler ultrasonic device, anthropometric factors or true genetic or environmental differences.