Can you draw blood from a double-lumen picc line which is used primarily for TPN?

Usually you do not draw blood from a line that is running TPN due to the concentrated electrolytes contained in the solution. If there is no other option the MD must be aware that the sample is taken from a TPN line so he/she can adjust the findings ANOTHER VIEW: PICC lines and other central access devices were not designed to have blood drawn from them for Lab tests. Specimen contamination is a serious problem for Lab whether the specimen is drawn from a single or double lumen PICCs. Even if the other lumen's infusion is shut off, the vacuum created in the lumen where blood is being drawn can cause contamination of the specimen. Often, even if the lumen is flushed properly and there is no contamination, the specimen may be hemolysed or clotted, making it useless for lab testing. In general, Lab will not report out results that they suspect are erroneous. This is because a Lab tech or physician cannot simply "adjust" findings due to an improperly collected specimen. This would be guesswork and is unacceptable in a health care setting where treatment often depends on reliable Lab results. Bottom line: check your facilities' policies and procedures regarding the use of PICCs and other central access devices for blood collection.