Mean arterial pressure
Total Peripheral Resistance (TPR) is represented mathematically by the formula:
R = ΔP/Q
R is TPR. ΔP is the change in pressure across the systemic circulation from its beginning to its end. Q is the flow through the vasculature (equal to cardiac output)
In other words:
Total Peripheral Resistance = (Mean Arterial Pressure - Mean Venous Pressure) / Cardiac Output
Therefore, Mean arterial pressure can be determined from:
- is cardiac output
- is systemic vascular resistance
- is central venous pressure and usually small enough to be neglected in this formula.
where is the pulse pressure,
At high heart rates is more closely approximated by the arithmetic mean of systolic and diastolic pressures because of the change in shape of the arterial pressure pulse.
If the falls below this number for an appreciable time, vital organs will not get enough Oxygen perfusion, and will become ischemic.
- Zheng L, Sun Z, Li J, et al. (July 2008). "Pulse pressure and mean arterial pressure in relation to ischemic stroke among patients with uncontrolled hypertension in rural areas of China". Stroke 39 (7): 1932–7. doi:10.1161/STROKEAHA.107.510677. PMID 18451345.
- Total peripheral resistance, Wikipedia
- Cardiovascular Physiology Concepts: Mean Arterial Pressure, Richard E. Klabunde, Ph.D
- Physiology at MCG 3/3ch7/s3ch7_4
- Cardiovascular Physiology (page 3)
- http://www.clinicalreview.com Physiology Review
- impactEDnurse (May 31, 2007). "mean arterial pressure". impactednurse.com. Retrieved 2010-12-25.
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