Central lines and TPN vs PPN - page 2
by emsillystudent 69,583 Views | 24 Comments
First of all, hi! I've been reading these forums for a long time, but this is my first post. I am relatively new to nursing, and I have a few questions. I recently started working as a unit secretary, and I was entering... Read More
- 0Feb 20, '08 by emsillystudentThank you guys all so much for your help! That really does clear things up. I knew that it must be one of the TPN components that caused a problem, I just didn't know which one. And thanks for letting me know what would happen if you did give it through a peripheral or a midline. I find it srange that my facility says no midlines for vanco, but it's ok to do it through a peripheral stick. I guess that must be because in a midline you would be less likely to notice problems right away?? Anyway, thanks again, that clears a lot of things up for me!
- 0Feb 21, '08 by CABG patch kidQuote from nbnurse95I hope it is <10% glucose? This seems bad for the patient, since you are supposed to change a peripheral site every 3 days, why not just get a PICC? I'm probably missing a few pieces of the puzzle here.Recently we've starting adm TPN through reg IV's. It's not as convenient since you only have the one line to work with so we usually have to start a second line for meds etc.
- 0Feb 21, '08 by siggie13Quote from Emmanuel GoldsteinTOOK THE WORDS RIGHT OUT OF MY MOUTH!!If you'll look at the order sheet at the ingredients of TPN vs PPN, you'll notice that PPN (peripheral parenteral nutrition) has a dextrose of 12.5% or less. Any IVF with a higher dextrose concentration must be given through a central line. (at some hospitals I've worked, the limit was 10%)
A PICC is a central line that is placed peripherally. A midline is a peripheral line. The difference is where the catheter tip lies; a PICC is threaded into the central circulation while a midline ends in the upper arm near the axilla. Because it is a peripheral line, you don't run TPN through a midline.
- 0Feb 21, '08 by siggie13Quote from nbnurse95Recently we've starting adm TPN through reg IV's. It's not as convenient since you only have the one line to work with so we usually have to start a second line for meds etc.
I'm with CAREBEAR on this one. The dextrose concent. has to be less than 10%, otherwise, it will thrombose vein and cause BIG problems. You can run lipids through a peripheral line without problems since it has a low dextrose content. I am interested in learning more about your TPN in Canada...could you please fill me in. Thanks.
- 1Feb 22, '08 by Daytonitewe had an incident on the last iv team i worked on where we had been called to restart one patient's iv 3 times in one day. when i was the one who went up to do the 4th restart within a 24 hour period i looked at the iv fluid that was infusing. it was tpn with a 50% concentration of glucose. it was never meant to be given peripherally. who made the mistake of hanging it, never knew. but, 50% glucose given over time in an iv infusion is caustic to the peripheral veins. no doubt, this patient will probably have 3 sclerosed and unusable veins forever due to this error. if only people had looked at the label of what was hanging, the outcome would have been much different for the patient.
as i mentioned, with central lines that terminate in the vena cava, the large amount of blood as well as the turbulence of the blood avoids the problem of mechanical phlebitis due to the caustic nature of the tpn solutions. the more solutes they put in these solutions, the higher the osmolality of the solution becomes and that means they are more hypertonic. peripheral veins cannot tolerate the constant flow of very hypertonic iv solutions.
there is good pathophysiology surrounding the theory of the use of these devices.
- 0Feb 26, '08 by nbnurse95Hi siggie13, I checked the policies and order forms at my hospital.
Our TPN for Central lines is as follows:
Amino Acids 5%, Dextrose 16.6% and Lipids 10 or 20%.
and for IV lives:
Amino Acids 2.7%, Dextrose 9% and Lipids 20%. There are also a few differences with the electrloytes.
"The lipids should be administered at the same time as the solution for peripheral parenteral nutrition. This simultaneous infusion diminishes osmolarity in the primary solution which favours prolonged usage of the peripheral vein".
I haven't seen a problem with the vein yet. It seems to work fine.
- 0Mar 22, '10 by TonsabubblyfunHi! I'm in nursing school right now and we are covering the whole central line thing right now. So for starters I don't know exactly what a midline is or what it is used for because we don't really see those, in fact the hospitals around us require the line to be in the SVC or they cannot be used (as far as I know so far at least) Second, TPN can't go through a peripheral line simply because it is what they call hyperosmolar (or >500) so it's viscous and the small veins in your periphery cannot handle it. Our teacher even mentioned that although PPN can go through a peripheral line, you still need to monitor it because it still carries some risks.
The vanco. answer is that vancomycin actually has a pH of 2.4-4.0 depending on how it was diluted. The veins of your periphery can really only handle pH's of about 5-9, so vanco. has a very high risk of extravasation, it's super acidic (like putting battery acid into your veins was the way it was explained to us). With that said a lot of hospitals near us have put policies into place just in the past year stating that the first dose of vanco. can go through a peripheral line, but after that the doses must be administered through a central line. Mostly because people have started noticing and requesting central lines for their patients to avoid those complications... Hope this helped and good luck with everything!!