It depends what you are on TPN for. TPN is not a long term solution for providing nutrition.
A G Tube is inserted directly into your stomach through your skin. You then receive liquid feedings through the tube. Some people receive continuous feeds at a slow rate. Others who are more active receive boluses throughout the day. The G Tube is generally easy to take care of and not difficult to be inserted. The biggest risk with a G Tube is the tube coming out. It happens more in children and disoriented adults. If it occurs, the doctor will have to insert another tube through the same hole that was previous used.
Good luck to you. I hope not eating is not long term for you!