system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: severed limb reattachment (e.g., which tissues in what order, success/fail factors, trauma-to-care time limits, etc.)
gpt
Med student here.

1) connect small vessels and nerves first, then the larger stuff like muscle. Better and easier to do it that way since otherwise you're working around big flesh pounds that are reconnected. So start with nerves and arteries/veins.

2) depends on what limb is severed but in general, the amount of time you have to get to a surgeon is about 4-5 hours. At the 5-6 hour mark tissue starts to die. The reason why reattachment is possible is because of this fact that limbs can survive detached for hours.

3) if you're going to transport a limb to a hospital, put it in a cooler. Don't put it in ice water, don't get it wet, keep it cool but not frozen. If it's a finger or toe, don't put it in your mouth, the bacteria fucks the digit up.