a few IV questions.....

PMFB-RN, RN · Nov 24, 2011

i'm struggling a bit with a few questions. the prof is known for poorly wording things, so i mostly want to see if other people read them/interpret the same way i do.......

1) what is the difference between a vad with two ports and one with two lumens?

a vad with two ports allows you to:

a) give incompatible iv fluids at the same time, each through a different port

b) give an incompatible iv push med when the other line is clamped and flushed.

*** i agree this is a poorly worded question. the answer is all the above

2) a central line has a higher risk than a peripheral line for:

air embolus - true/false?

site infection/sepsis - true/false?

losing large amounts of blood if the line is left open - true/false?

*** true, true & true.

3) if a patient with cellular dehydration is given d5w, will the intracellular fluid volume go up, down or stay the same?

*** water alwasy goes to the higher concentration of salt. there is no salt in d5w but there is in our cells so the water will go into the cells.

That Guy, BSN, RN, EMT-B · Nov 24, 2011

WHat do you think the answers are? Dang Someone already answered ha ha.

But yes I agree what ^ said

nurseprnRN, BSN, RN · Nov 24, 2011

1) what is the difference between a vad with two ports and one with two lumens?

well, that's sort of the main point, isn't it? your prof isn't being obscure here, she's asking if you know a straight definition.

a lumen is the tube that runs down to the end, or somewhere near the end, of the catheter. iv catheters can have one lumen, two, three, or (rarely) more. they are separate tubes-within-a-tube and their contents do not mix.

a port is the site outside the body where you can plug something in. a lumen can have two ports that both inject into the same lumen. generally a multi-lumen line has one port per lumen. now you should be able to figure out the next answer and give rationales.

a vad with two ports allows you to:

a) give incompatible iv fluids at the same time, each through a different port

b) give an incompatible iv push med when the other line is clamped and flushed.

2) a central line has a higher risk than a peripheral line for:

air embolus - true/false? depends. if she means, if the line is left open to air, it's true, because spontaneous inhalation will decrease intrathoracic pressure and suck air into the trachea and the open iv line (that's also a tube going into the chest). if she means, because somebody injects air into it, same; anybody can inject air into anything. if she means, a dangerous amount of air (as opposed to any old air bubble, which is an embolus too), it's true.

site infection/sepsis - true/false? site skin infection, no difference at the site. sepsis is, well, sepsis (this means more than just "local infection"), but an infected central line insertion site can develop a worse problem a lot faster than an infected peripheral one (you'd find the peripheral one's problem first).

losing large amounts of blood if the line is left open - true/false? also depends on patient anticoagulation, position of the site relative to the vena cava (a unplugged peripheral iv in a forearm dangling over the edge of the bed can put out an astonishing amount of blood), central venous pressure; but generally, a central line is larger in caliber than a peripheral line, so it will carry larger amounts of blood and not clot off as easily, either.

3) if a patient with cellular dehydration is given d5w, will the intracellular fluid volume go up, down or stay the same? aha, that's a straightforward do-you-know-your-permeability-and-fluids-osmolarity-physiology lesson question, not tricky at all if you learned that very basic material. go try again to look up the osmolarty of iv fluids, what that means, and how fluids distribute intracellularly and extracellularly, and ask again if you can't figure it out from there.

nashgirl516 · Nov 24, 2011

Thanks for the input. For the first question (about lumens vs ports) I have to pick A -or- B... so even though I know the difference, that isn't the question... it is whether A or B is right, but they BOTH are, so I don't know which to put.

For #2, I ran into some of the same situations as GrnTea.... it is difficult to just pick true or false, when there are way too many unmentioned variables to consider.... but I just have to go with what she has written and pick true or false. I'm thinking about just going with my gut and saying true for all three.

As for #3, I am assuming the intRAcellular fluid volume will increase, but the intERcellular fluid would remain the same....?

Like I said, I just don't like the way she words a lot of questions... there are more, but I've gotten to the point where I just take my best guess at what she is trying to get at.

Thanks, again!! If anyone else has any input, feel free to add!!

nurseprnRN, BSN, RN · Nov 24, 2011

". for the first question (about lumens vs ports) i have to pick a -or- b... so even though i know the difference, that isn't the question... it is whether a or b is right, but they both are, so i don't know which to put."

no, they are not both right, only one is. let's take this apart.

1) what is the difference between a {{vad with two ports}} and {{one with two lumens}}?

the way this is worded tells me that the one with two ports does not have two lumens, only one.

a vad with two ports allows you to:

a) give incompatible iv fluids at the same time, each through a different port

you cannot give two incompatible substances at the same time in one lumen.

b) give an incompatible iv push med when the other line is clamped and flushed.

this you can do-- push med #1 in through port#1 after the other iv in port#2 is clamped and flushed. then flush before resuming the med in post#2 so it will not encounter any med#1 in the single lumen they both use(d).

as for #3, i am assuming the intracellular fluid volume will increase, but the intercellular fluid would remain the same....?

what is "intercellular fluid"? do you mean "extracellular"? the water in the d5w will enter the cells, so intracellular fluid increases.