As a simplification you can express it as a mean value of blood pressure.

Simply speaking- it is often calculated as diastolic pressure + 1/3 of difference between systolic and diastolic pressure or registered as mean pressure by automatic systems

Mean Arterial Pressure (MAP)= [SBP + (2 × DBP)]/3.

I agree with Tomasz Zielinski, the mean blood pressure reflects both Systolic and diastolic blood pressure.

The difference between Systolic and diastolic blood pressure is known as pulse pressure. Mean blood pressure is equal to diastolic blood pressure plus one third of pulse pressure. The calcification is valid for both systemic and pulmonary blood pressure.

You can definitely use MAP, with the equation as above, and this would be the most accepted way. Just be cognizant that this may have unexpected effects on your analysis depending on the population you are studying and the questions you're asking.

1. Know the assumptions underlying this equation, as it is an approximation of the true MAP (i.e. the MAP you'd obtain with invasive catheter based monitoring). In healthy(ish) people and/or with a large enough sample size MAP calculated this way shouldn't be a big issue. However, in acutely-ill populations (e.g. hospitalized patients with a condition of major hemodynamic significance), the equation above may not work great. The assumption is that diastole is 2/3rds of the cardiac cycle, but in patients with acute heart failure, shock, arrhythmias, and other hemodynamic derangements this assumption is often invalidated (i.e. diastole makes up a different proportion of the cardiac cycle, which may vary between patients and even beat to beat). However, if all you care about is BP as a general risk factor for a population based problem, none of this will likely matter

2. Note that for certain conditions, the different measures of blood pressure (SBP, DBP, and MAP) actually have different correlates. Again, this depends on your question, but for some conditions SBP may be more strongly correlated with your response variable than DBP or MAP (or visa-versa) because of physiologic reasons specific to the population and question you're studying. For instance, SBP has a roughly equal correlation with cardiac index (CI) and vascular tone in acute heart failure patients, while DBP has virtually NO correlation with CI but a much stronger correlation with vascular tone. In some conditions, like sepsis, MAP is a better predictor of mortality than DBP, whereas in heart failure SBP is a better prognostic predictor. Also, the pulse pressure (SBP-DBP) is associated with other factors which may affect your analysis such as age (pulse pressure tends to widen) or severity of hemodynamic instability (pulse pressure tends to narrow). Again, if this is outpatient community based research this probably doesn't make a big difference, but in the acute care setting it can.

https://pubmed.ncbi.nlm.nih.gov/33611627/

If you only want to use one number, use systolic blood pressure because it is related to atherothrombotic disease, while diastolic blood pressure is not.

Dear William Feeman

Low diastolic blood pressure (DBP) and increased mortality in the elderly

However, a lower diastolic BP (DBP

Dear William Feemen Sir, Nicholas Harrison and Muhammad Yousuf. Thank you for your wonderful and much informative remarks and references and highlighting the importance of Systolic, diastolic and mean pressure especially in reference to haemodynamic and prognosis in various setting. .And it seems that each parameters may suit specific condition. But If a single parameter is to be chosen, I humbly propose, mean BP can more acceptable (if not truly representative). In pulmonary artery pressure and in patients with shock, mean pressure is considered widely . In cardiology practice mean pressure gradients are widely used as measure in decisions making rather than the peak gradient.

Regards.

I thought that the J-curve for diastolic BP did have prognostic significance in predicting adverse outcomes in those with atherothrombotic disease. I maintain that if only one number is to be used, then it should be systolic BP, though I do acknowledge that some papers have been written using mean arterial BP.

Mean Arterial Pressure (MAP) is a single BP monitoring tool particularly important in patients who are hemodynamically unstable in Intensive Care Unit (ICU), Coronary Care Unit (CCU), Operation theater, and during dialysis or invasive cardiac procedures. Value of MAP is dependent on both SBP and the DBP.

Please have a look at these lined articles about MAP:

1. Article The importance of mean arterial pressure as a patient assess...

2. Article Mean Arterial Pressure Classification: A Better Tool for Sta...

3. Article The relationship between the prognosis and mean arterial blo...

4. Article Determinants of mean arterial pressure and pulse pressure in...

Just to trail the discussion that has been a little bit far from the original question. There are some more scenarios where MBP is used, e.g., when perfusion pressure for vital organs is a concern, or when the function of baroreceptor reflex or autonomic nervous system needs to be known…; for the purpose of diagnosis and prognosis, both systolic and diastolic pressures have to be reported - the guidelines for diagnosing and treating hypertension do not use MBP. The fact is, however, MBP is easily calculated when the readings of both systolic and diastolic pressures are available, not the other way around. So is pulse pressure, which cannot be calculated from MBP only, but is important in reflecting cardiac function and predicting outcomes (e.g., atrial fibrillation, cardiovascular mortality...).

Please correct me if I'm wrong.

Mean arterial pressure can be calculated from systolic and diastolic blood pressure and used as a single variable.

Mean arterial pressure= diastolic BP+1/3 of pulse pressure

Dear colleague

I think the best way to evaluate the all three of systolic ,diastolic and mean arterial pressure because all three are important and may be have effect on variables . I recommend to compare the effect of three variable with important index.

Yes systolic blood pressure and diastolic blood pressure can be converted (expressed as) Mean arterial blood pressure (MAP) . One third of systolic blood pressure plus two third of diastolic pressure gives mean arterial pressure.