Systemic Vascular Resistance Calculations
Contents [hide]
Systemic Vascular Resistance Calculations
Calculate Systemic Vascular Resistance – given
- Systolic pressure: 130 mmHg
- Diastolic pressure: 90 mmHg
- Right atrial mean pressure: 4 mmHg
- Cardiac output: 5 L/min
Calculate systemic vascular resistance in Wood units
[A] 8 Wood unit
[B] 10 Wood unit
[C] 13 Wood unit
[D] 21 Wood unit
Mean arterial pressure
= (2 diastolic pressure + systolic pressure)/3
= 2X 90 + 130 = 210/3 = 70 mmHg
Systemic vascular resistance
= [MAP-CVP] / C.O
= (70 – 4) / 5
= 13.2 Wood unit
Normal: 900-1200 dynes.sec.cm-5 or 11-15 Woods Units.
Hybrid resistance units (HRU) – also known as Wood units in honor of Paul Wood.
1 HRU = 1 Woods unit = 80 dyne.sec/cm5 = Pa·s/m3
Pa = pascal = pascal (symbol: Pa) is the unit of pressure in the International System of Units , 1 pascal = N/m2
- Wood units is used to measure – Peripheral vascular resistance
Units for measuring vascular resistance
- dyn·s·cm−5
- pascal seconds per cubic metre (Pa·s/m3)
- mmHg·min/L. – called as hybrid resistance units (HRU) , also known as Wood units