If someone has had an accidental finger amputation, what happens next?

Variable by injury: Depends on the level of the amputation, type of surgical care, and degree of zone of injury. Seek care from hand surgeon. No generalities will apply to all amputations.

Health, mechanism: Of injury and level of injury affects whether or not a replantation or reattachment is offered. Smokers, circulation issues, avulsion injury, multiple level injury all have worse prognosis. Sometimes the better reconstructive procedure is to leave it "un-reattached "and care for the injury site . Transport the part in a plastic bag in moist guaze in another bag that has ice, not in water.