Rule of thumb to calculate mean arterial pressure at the brachial artery level

Verrij, Elisabeth; Vincent, H. H.; Bos, Willem Jan W.

doi:10.1097/hjh.0b013e3282f5eaf3

Cited by 10 publications

(5 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The original exponential calibration scheme proposed by Meinders et al used an approximate measure for mean arterial pressure defined as MAP = DBP + (SBP -DBP)/3. Though this approximation is often used, it differs significantly from MAP calculated as the true mean of the arterial waveform (Bos et al 2007, Verrij et al 2008. When using the approximated value for MAP, the exponential calibration procedure underestimates SBP by 13.2 (5.7) mmHg, the difference being mostly due to the different estimation of MAP used for calibration.…”

Section: Discussionmentioning

confidence: 99%

Determining carotid artery pressure from scaled diameter waveforms: comparison and validation of calibration techniques in 2026 subjects

Vermeersch¹,

Rietzschel²,

Buyzere³

et al. 2008

Physiol. Meas.

View full text Add to dashboard Cite

Calibrated diameter distension waveforms could provide an alternative for local arterial pressure assessment more widely applicable than applanation tonometry. We compared linearly and exponentially calibrated carotid diameter waveforms to tonometry readings. Local carotid pressures measured by tonometry and diameter waveforms measured by ultrasound were obtained in 2026 subjects participating in the Asklepios study protocol. Diameter waveforms were calibrated using a linear and an exponential calibration scheme and compared to measured tonometry waveforms by examining the mean root-mean-squared error (RMSE), carotid systolic blood pressure (SBPcar) and augmentation index (AIx) of calibrated and measured pressures. Mean RMSE was 5.2(3.3) mmHg (mean(stdev)) for linear and 4.6(3.6) mmHg for exponential calibration. Linear calibration yielded an underestimation of SBPcar by 6.4(4.1) mmHg which was strongly correlated to values of brachial pulse pressure (PPbra) (R = 0.4, P < 0.05). Exponential calibration underestimated true SBPcar by 1.9(3.9) mmHg, independent of PPbra. AIx was overestimated by linear calibration by 1.9(10.1)%, the difference significantly increasing with increasing AIx (R = 0.25, P < 0.001) and by exponential calibration by 5.4(10.6)%, independently of the value of AIx. Properly calibrated diameter waveforms offer a viable alternative for local pressure estimation at the carotid artery. Compared to linear calibration, exponential calibration significantly improves the pressure estimation.

show abstract

Section: Discussionmentioning

confidence: 99%

Determining carotid artery pressure from scaled diameter waveforms: comparison and validation of calibration techniques in 2026 subjects

Vermeersch¹,

Rietzschel²,

Buyzere³

et al. 2008

Physiol. Meas.

View full text Add to dashboard Cite

show abstract

“…Pd and mean pressures (Pm) were set equal at brachial and central aorta (30,34,39): Pd brachial pressure (Pdb) ϭ Pd aortic pressure (Pda) and brachial Pm (Pmb) ϭ aortic Pm (Pma). We used the following form factors (FFs) [the ratio of (Pm Ϫ Pd)/pulse pressure (PP)] to derive mean brachial artery and central aortic pressure, FF ϭ 0.33 (11,57) and FF ϭ 0.40 (4,6,49), respectively.…”

Section: Methodsmentioning

confidence: 99%

Aortic function quantified: the heart's essential cushion

Saouti

Marcus

Noordegraaf

et al. 2012

Journal of Applied Physiology

View full text Add to dashboard Cite

Arterial compliance is mainly determined by the elasticity of proximal large-conduit arteries of which the aorta is the largest contributor. Compliance forms an important part of the cardiac load and plays a role in organ (especially coronary) perfusion. To follow local changes in aortic compliance, as in aging, noninvasive determination of compliance distribution would be of great value. Our goal is to determine regional aortic compliance noninvasively in the human. In seven healthy individuals at six locations, aortic blood flow and systolic/diastolic area (ΔA) was measured with MRI. Simultaneously brachial pulse pressure (ΔP) was measured with standard cuff. With a transfer function we derived ΔP at the same aortic locations as the MRI measurements. Regional aortic compliance was calculated with two approaches, the pulse pressure method, and local area compliance (ΔA/ΔP) times segment length, called area compliance method. For comparison, pulse wave velocity (PWV) from local flows at two locations was determined, and compliance was derived from PWV. Both approaches show that compliance is largest in the proximal aorta and decreases toward the distal aorta. Similar results were found with PWV-derived compliance. Of total arterial compliance, ascending to distal arch (segments 1-3) contributes 40% (of which 15% is in head and arms), descending aorta (segments 4 and 5) 25%, and "hip, pelvic and leg arteries" 20%. Pulse pressure method includes compliance of side branches and is therefore larger than the area compliance method. Regional aortic compliance can be obtained noninvasively. Therefore, this technique allows following changes in local compliance with age and cardiovascular diseases.

show abstract

“…Instead, we used pulse-wave analysis was as our gold standard. 3 The MAP displayed by the WatchBP Office oscillometer was significantly lower than the MAP found by pulse-wave analysis. The percent PP that had to be added to the DBP to obtain the MAP provided by oscillometry did not correlate with values found by pulse-wave analysis.…”

Section: Discussionmentioning

confidence: 72%

“…Recent studies indicate that this results in underestimation of the MAP in virtually all subjects. 1,3 The recently proposed rule of adding 40% of the PP to the DBP gives better average results, but does not give optimization of individual MAPs. 1 Theoretically, oscillometric measurement is the optimal technique for precisely determining MAP.…”

mentioning

confidence: 99%

Inaccuracy in Determining Mean Arterial Pressure With Oscillometric Blood Pressure Techniques

Vos

Vincent

Verhaar

et al. 2013

American Journal of Hypertension

View full text Add to dashboard Cite

ObjectiveAccurate determination of MAP is important in the calibration of pressure waveforms for calculating central blood pressure (BP). Currently, a precise, individualized measurement of mean arterial pressure (MAP) can be obtained only with intra-arterial measurements of BP or with applanation tonometry. We conducted a study of whether easy-to-use oscillometric devices, validated for systolic and diastolic BP measurements (BHS protocol), give accurate determinations of MAP. MethOdsWe compared measurements of MAP made with the WatchBP Office oscillometric monitor in 102 subjects with values of MAP assessed by pulse-wave analysis (PWA) (SphygmoCor). ResultsThe mean (± SD) oscillometric MAP assessed with the WatchBP Office monitor was 97 ± 12.5 mm Hg, which was equivalent to 23.6 ± 9.1% of the pulse pressure (PP) above diastolic blood pressure (DBP). The MAP as assessed through PWA was 106 ± 14.6 mm Hg (P < 0.01), or 37.7 ± 3.9% of the PP above DBP. In simultaneous measurements made on both arms with the WatchBP Office monitor we observed individual differences in pressure in the left vs. the right arm. cOnclusiOnsThe MAP displayed by the WatchBP Office monitor is too imprecise to be used for calibrations. We suggest that devices for measuring BP not display MAP unless their accuracy is tested.Keywords: mean arterial pressure; oscillometric; pulse-wave analysis; tonometric; pulse pressure; hypertension; blood pressure. doi:10.1093/ajh/hps072The mean arterial pressure (MAP), as calculated from the systolic and diastolic blood pressures (BPs), varies among individuals. 1 The accurate determination of MAP is important in calibrating pressure waveforms to calculate central BPs. 2 The prognostic importance of the MAP in epidemiological research may be underestimated as the result of its incorrect calculation.Traditionally, MAP is calculated by adding 33% of the pulse pressure (PP) to the diastolic blood pressure (DBP). Recent studies indicate that this results in underestimation of the MAP in virtually all subjects. 1,3 The recently proposed rule of adding 40% of the PP to the DBP gives better average results, but does not give optimization of individual MAPs. 1 Theoretically, oscillometric measurement is the optimal technique for precisely determining MAP. Maximal pressure oscillations in the instrument cuff on the subject's upper arm occur when the vessel wall is maximally unloaded, i.e. at the moment that the cuff pressure equals the MAP. 4,5 At this moment a precise, individualized measurement of MAP can be obtained only with intra-arterial BP measurements 6 or with applanation tonometry. 1 The former method requires invasive procedures, the latter is elaborate. We investigated whether MAP can be measured accurately with easy-to-use oscillometric devices that are validated for measurements of systolic and diastolic BP according to the British Hypertension Society (BHS) protocol. 7 Although oscillometric measurements are based on determining MAP, only a few devices provide the MAP itself. We selected a device tha...

show abstract

Rule of thumb to calculate mean arterial pressure at the brachial artery level

Cited by 10 publications

References 6 publications

Determining carotid artery pressure from scaled diameter waveforms: comparison and validation of calibration techniques in 2026 subjects

Determining carotid artery pressure from scaled diameter waveforms: comparison and validation of calibration techniques in 2026 subjects

Aortic function quantified: the heart's essential cushion

Inaccuracy in Determining Mean Arterial Pressure With Oscillometric Blood Pressure Techniques

Contact Info

Product

Resources

About