A tractor-trailer accident on I-40 in Cumberland County early this morning left the driver with serious injuries. According to the report released moments ago, a 2017 Freightliner operated by 54-year-old Paul Gamboa of Greenback was traveling west at the 323 mile marker when he fell asleep, ran off the road, the came back onto the interstate crossing both westbound lanes. The tractor-trailer then rolled over several times before coming to rest on its side facing east in the median. Gamboa was flown by an air medical helicopter to Vanderbilt Medical Center for treatment of potential life threatening injuries. Westbound traffic was down to one lane at the scene of the crash for several hours this morning.