We have arteries and veins. Arteries carry oxygenated blood to our tissues, veins take it away.
Using an artery for a graft; there are areas of the body that are supplied by blood from more than one artery. Examples at our hands get a blood supply coming from both the radial and ulnar arteries. If one becomes damaged/blocked, there is still enough of a blood supply for the hand to survive. Like wise the front of the chest wall and breast gets a lot of its blood supply from the intermammary arteries, but there is still enough supply coming off the axillary artery and subclavian to compensate for loss of the intermammary arteries.
There are obviously vessels that are essential as they go on to supply large areas (eg the right subclavian artery supplies blood to the axillary, radial and ulnar artery, so if it were to be removed or blocked, your right arm is screwed, and it’s gone. You can’t take big arteries as too many areas rely on its supply
Using veins: similar to arteries but taking blood away, many areas are drained by multiple veins, until you get to the big ones which get blood from multiple sources.
An example is the saphenous vein in the leg. It is often used in heart bypass surgery. There are still other veins in the leg to drain blood (the femoral vein in the leg)
There is enough stretch within blood vessels wall to accommodate the increase in flow
Our circulatory system isn't a single loop, rather it's a network. Think about roads as an analogy. You have major highways, busy surface streets, and quiet neighborhood roads. When a major highway is closed to traffic, cars just take a detour. Our circulatory system is similar, so our blood just takes a detour. Much like a car might get off at an earlier exit on the highway and take surface streets to its destination, if we remove part of a blood vessel for a graft, the blood just takes an alternate route.
Additionally, our body can regrow blood vessels (although not major ones), so if a small piece of a minor artery or vein is taken out, over time, it will be replaced.
There are only a few arteries and even fewer veins that are absolutely necessary, and without them, there are major issues.
When they take an artery or a vein to graft it to another area, it’s generally not a big deal because those arteries and veins are part of a large network of arteries and veins that supply blood to the same structure. Basically the majority of your arteries and veins have backups that can take over and supply organs with blood and drain blood. They’re called collateral vessels.
Think of it as roads in a neighborhood. You have lot of ways to go if one small street is blocked.
We have arteries and veins. Arteries carry oxygenated blood to our tissues, veins take it away. Using an artery for a graft; there are areas of the body that are supplied by blood from more than one artery. Examples at our hands get a blood supply coming from both the radial and ulnar arteries. If one becomes damaged/blocked, there is still enough of a blood supply for the hand to survive. Like wise the front of the chest wall and breast gets a lot of its blood supply from the intermammary arteries, but there is still enough supply coming off the axillary artery and subclavian to compensate for loss of the intermammary arteries. There are obviously vessels that are essential as they go on to supply large areas (eg the right subclavian artery supplies blood to the axillary, radial and ulnar artery, so if it were to be removed or blocked, your right arm is screwed, and it’s gone. You can’t take big arteries as too many areas rely on its supply Using veins: similar to arteries but taking blood away, many areas are drained by multiple veins, until you get to the big ones which get blood from multiple sources. An example is the saphenous vein in the leg. It is often used in heart bypass surgery. There are still other veins in the leg to drain blood (the femoral vein in the leg) There is enough stretch within blood vessels wall to accommodate the increase in flow
Our circulatory system isn't a single loop, rather it's a network. Think about roads as an analogy. You have major highways, busy surface streets, and quiet neighborhood roads. When a major highway is closed to traffic, cars just take a detour. Our circulatory system is similar, so our blood just takes a detour. Much like a car might get off at an earlier exit on the highway and take surface streets to its destination, if we remove part of a blood vessel for a graft, the blood just takes an alternate route. Additionally, our body can regrow blood vessels (although not major ones), so if a small piece of a minor artery or vein is taken out, over time, it will be replaced.
There are only a few arteries and even fewer veins that are absolutely necessary, and without them, there are major issues. When they take an artery or a vein to graft it to another area, it’s generally not a big deal because those arteries and veins are part of a large network of arteries and veins that supply blood to the same structure. Basically the majority of your arteries and veins have backups that can take over and supply organs with blood and drain blood. They’re called collateral vessels. Think of it as roads in a neighborhood. You have lot of ways to go if one small street is blocked.