- Joined
- Jun 11, 2015
- Messages
- 174
- Reaction score
- 42
KLN 2016 Physiology
LaPlace relationship:
Wall tension is proportional to pressure * radius.
The aorta is the artery with the greatest wall tension (greatest pressure and radius).
I understand that increasing pressure increases wall tension of a vessel.
But how does a larger radius mean a higher wall tension? Does it mean, "increasing radius beyond its normal radius increases wall tension"?
If you had two vessels: each have the same pressure, but one had a large radius and one had a small radius, but both have wall thickness proportional to their radius, why would the larger radius vessel have a greater wall tension?
I fully understand that if you have two deflated balloons, if you inflated one to about 10cm vs one to 50cm, the 50cm one would have way higher wall tension. But this is because you're expanding the radius without increasing the thickness. The aorta does have a larger radius than other arteries but its much thicker than other arteries... so I don't understand how simply having a larger radius increases wall tension.
Like why would a small tube with thin walls (arteries) have lower wall tension than a large tube with thick walls (aorta), if their pressure was the same.
LaPlace relationship:
Wall tension is proportional to pressure * radius.
The aorta is the artery with the greatest wall tension (greatest pressure and radius).
I understand that increasing pressure increases wall tension of a vessel.
But how does a larger radius mean a higher wall tension? Does it mean, "increasing radius beyond its normal radius increases wall tension"?
If you had two vessels: each have the same pressure, but one had a large radius and one had a small radius, but both have wall thickness proportional to their radius, why would the larger radius vessel have a greater wall tension?
I fully understand that if you have two deflated balloons, if you inflated one to about 10cm vs one to 50cm, the 50cm one would have way higher wall tension. But this is because you're expanding the radius without increasing the thickness. The aorta does have a larger radius than other arteries but its much thicker than other arteries... so I don't understand how simply having a larger radius increases wall tension.
Like why would a small tube with thin walls (arteries) have lower wall tension than a large tube with thick walls (aorta), if their pressure was the same.