The line most of you are talking about in the head and foot...would be an Intravenous line. The line sandrass is talking about is a PICC /Central line which is placed into an artery. These go straight to the heart, instead of veins which go through the body and back to the heart.
A picc line is generally place in the interior part of the upper arm. A central line is typically place in the carotidid(neck), thigh, or sometimes on the chest wall. These lines are put in a very sterile field and doctors are required to put them in. These lines are used for crictical patients or patients requiring many lab draws, medications, or long term use.
Sandrass, My preemies never required a Picc/or central line, but personally I had one due to hyperemesis. I also am an RN so know some information on them.
First of, if you dont mind, why does she have a PICC line? The most important thing is to always keep the line clean and free of germs. If a picc line gets infected that is a very serious thing. Signs would be swelling/reddness around the site, increased pain, fever. These are signs that something maybe infected. I'm sure they told you this, so sorry if I am repeating what they said.
PICC lines can be scary but they are very benificial, depending on the reason for it. Sometimes I think babies should recieves these if they know it's going to be a long stay. Because venous lines need to be changed every 4 days and they can go bad very easily. With the Picc line it's just one poke!
If you have any ?'s feel free to respond. I hope I've been some help. Hugs to you and your baby.