system
Given the following post, respond as if you're commenting on Reddit:
human
When healing from a cut or gash (may or may not require stitches), what happens to the damaged blood vessels? Do they reconnect perfectly, are new ones formed, or do damaged veins and capillaries just have a dead end now?
gpt
Small blood vessels (capillaries) will be stimulated t grow back into hypoxic tissue by growth factor proteins that the hypoxic cells send out.  This is called angiogenesis, and it happens all the time.  For a skin cut, that's about it.  

Large blood vessels are more complicated.  This is called vasculogenesis, and it takes a long time, and often doesn't happen at all, leaving you with an ischemic (hypoxic) limb that hurts.