Originally Posted by pudendum
I hope you don’t mind, but I’m going to correct something you said. As I said in an earlier post, lymph is the fluid in lymph vessels that drain to lymph nodes and ultimately back into the blood circulation. Fluid outside cells is called extracellular fluid (ECF). When ECF increases and causes swelling (aka, fluid build up) it is called edema. This edema fluid will overtime enter the lymph channels and “become” lymph. It may sounds like a case of semantics, but this is the more correct terminology. It’s kinda like capitalizing Kegel, it’s just what it’s called.In a couple of posts ttt and I talked about the factors that cause fluid to leave the blood vessels (at the capillaries) and become ECF (and if too much, edema). It is a balance between 2 factors. One is the pressure difference between inside of the capillaries (which is 30 - 50 mm Hg) and outside the capillaries (which can be between -3 to 5 mm Hg). This difference would cause the fluid in the blood to exit the vessels and become ECF. The other factor is caused by the differences between the amount of proteins inside (high) and outside (low) the capillaries. Blood proteins do not pass out of the capillary. This difference in proteins tends to draw water back into the blood vessels by osmosis and “holds on” to it; water travels back into the capillary because amount of water is higher outside the vessel and lower inside the blood because of the proteins. (Mravg - this is a difference between hydrostatic pressure and oncotic pressure).
The balance between these 2 factors in normal situations keeps fluid inside the blood vessels. There is a small leak normally and this is why there is a lymphatic system in the first place; take ECF back to the blood and keep the space outside of the cells relatively “dry.”
Pumping and clamping alter this balance.
Pumping causes the pressure outside the capillaries to become very negative. This causes the pressure difference between inside and outside to become even larger. This causes fluid to exit and increase ECF. As pumping is sustained, the negative pressure difference remains high and over time fluid builds up (edema).
Clamping increases the pressure in both the arteries and veins so that the pressure difference across the capillaries gets higher and fluid would leave into the the ECF. The difference between clamping and pumping is that the clamps keep the ECF from moving around and leave the penis. Because of this, pressure outside the capillaries rises quickly, balancing the pressure difference and the fluid loss will be small. The other thing is that clamp times are short, so the time for fluid loss is also short.
I think this is the reason for the differences in fluid build up (edema) between pumping and clamping. I hope this is clear.
The main reason is that in pumping the primary pressure effect is under the skin (where the edema forms) but in clamping it is under the tunica. Therefore, clampers usually experience no or little edema at least compared to pumpers.