Help with Son's Medical Needs

My son was in a horrific accident last week, a tractor trailer came into their lane doing 35mph the truck he was in was going 70+ mph and couldn't stop so they hit the trailer. The driver of the Tractor Trailer fled the scene. My son was Life Flighted to Grady Memorial Trauma Center where he was on a ventilator for 2 days in CICU. It is a miracle and only by the Grace of God he survived the accident at all he has no insurance and since the other driver left we are responsible for medical bills