Can anyone explain to me the rationale behind this order?

Nurses Medications

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Just some background on the patient-elderly man, severe abdominal pain, dehydrated. He was NPO, had NG tube to constant suction with a large amount of drainage coming out. CT of abd was negative. He hadn't had a bm in a few days so the GI doctor ordered a retention enema which was given with good results. Labs were pretty stable, but did have a potassium of 3.3, which we gave him po potassium based on the protocol in place. He was already getting normal saline at 125 ml/hr. That's the background.

So the resident doctor came and wrote an order for Lactated Ringers at 100ml/hr and D5NS at 100 ml/hr to run at the same time. I have never seen an order like that and just did not understand the rationale behind it, neither did any of the other nurses I work with, another doctor, nor the pharmacist. I called and clarified this with the doctor and he came back to the floor to talk to me. He said he asked his attending and superiors and they all agreed to the order, when I asked him the rationale behind why LR and D5NS, he said he didn't really know and that he would be researching that. I've tried to find some information on it, but can't. Anybody have anything?

and you did pull the ng before you gave him po kcl, right? else you could have just put it directly into the suction cannister, :D .

didn't have to pull the ng before giving. the ng tube was clamped during and for about an hour after med administration. the patient was able to swallow pills with the ng tube in place. i didn't give kcl iv because there was not an order for iv, only po. yes i could have obtained an order, but since the patient was already taking po meds while the ng tube was clamped, i didn't see the need to do so.

I can only think that maybe it had something to do with the patient's acid/base balance, and wanting to keep him from tipping into the acidotic side with the NS. Did you have a pH on him?

No, ABG's were not drawn.

Doesn't matter if it was placed in his NG or he swallowed it. If the NGT is at continous suction the KCL is just going to be sucked back up into the cannister. You would need to clamp the NG tube.

^^

That is a given to me.

It's a given to me too. I'm kind of offended at the assumptions that I don't know basic nursing or have a lick of common sense!

An enema will NOT fix a bowel obstruction. Unless it was a very low partial obstruction.

The K is usless given PO as it is not absorbed. That is the rationale for the NG. What goes in must come out if the usual exit route is blocked it will reverse up the entrance. So no matter how long you clamp the NG it will still be there.

Because the GIT has lost the absorption function electrolytes are not being absorbed causing K+ derangement.

I don't understand the,rationale in the choice of fluid resus.

From a colorectal nurse who has just spent a night shift explaining this very thing to a grad.

This does make sense. So why would the doctors have us continue giving all of his PO meds and clamping the ng tube if they were all not going to be absorbed anyways?

I don't understand why we would give both LR and NS at the same time. Since both NS and LR are volume expanders and do basically the same thing aside from the LR containing some electrolytes. In that case, I understand giving the LR because it contains electrolytes, which he needed, so why not just give D5LR at a higher rate instead of running two different solutions?

I am guessing there is no rationale for that order and that the resident misunderstood the directions of his supervisor. Usually when no one can come up with a reason for doing something (nurses, MDs, pharmacists) it is usually because it is wrong.

Well, I'm just guessing here, but: D5NS because he is NPO and doesnt have a PEG, so he needs something for energy. LR has 4 mEq of potassium in it, for the K of 3.3.

Specializes in Emergency.

I don't know. But I would like to give kudos to the resident for admitting he didn't know and going off to research it, instead of getting all defensive and saying "Because I and Dr X and Dr Y say so!"

aaaand they moved a post of mine again....I forgot why I was so annoyed with allnurses. There's so many different forums on this website I'm sure every single post in the general forum has a "spot"...that nobody would know or care to go to. :rolleyes:

Well, I'm just guessing here, but: D5NS because he is NPO and doesnt have a PEG, so he needs something for energy. LR has 4 mEq of potassium in it, for the K of 3.3.

Yeah, I thought of that too, but if the patient needed the D5, they could just have the D5LR and the problem would be solved without needing to add in the NS.

I'm just gonna chalk it up to there was no rationale for this order and maybe the resident didn't know we could do D5LR...and maybe another poster above was spot on and the resident might have misunderstood directions from his superior.

Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.
it *sounds* like they could be used as a volume expander (r/t dehydration), in addition to raising his k+ level by bringing it back into cells.

it should only used short term.

leslie

i agree with leslie. lr is slightly hypotonic and converts to bicarbonate when metabolized. d5ns is slightly hypertonic and causes the push/pull effect that will effect the k move form extracellular to intracellular. the removal of copious amounts of gastric contents will cause acidosis and dehydration. i have seen this technique used in the effect that one is the cc/cc fluid replacement for gastric content and the other is fluid replacement/maintenance.

this needs to be used with great caution in a compromised elderly patient. large amounts of volume will be difficult for this population to deal with and the potential for heart failure/volume overload is almost assured if not monitored closely. be careful this time of year when the med students are fresh on their rotations.

there's no one ideal fluid for every situation. for resuscitation, crystalloids allow rapid repletion of volume. 0.9% sodium chloride is slightly hypertonic compared to plasma (308 mosm/l vs 290). lactated ringer's is slightly hypotonic (273 vs 290). since they are both so close to plasma, they are considered the isotonic fluids. you can get a hyperchloremic metabolic acidosis from large volumes of 0.9% nacl (typically 5+liters). you can get hyponatremic from large volumes of lr. either are acceptable for volume resuscitation.

for maintenance, sodium content and tonicity matters. if you use 0.9% nacl for an extended amount of time, the plasma sodium content will increase and you may get hypernatremic. to avoid this, solutions like 0.45% or lower are used. if the patient is not eating, and you are concerned about providing calories to prevent protein breakdown, dextrose is added to the fluid. 3 liters of a 5% dextrose solution provides 500 kcal a day enough to be protein sparing. adding d5 to ns results in a hypertonic solution (560 mosm/l). if the patient's glucose metabolism is impaired, you could cause cellular dehydration from the hypertonic solution. d5 0.45% nacl avoid this.

i don't care about the med student but i do care about you......this charts may help you.....they were made by a great nurse here daytonite (rip).

table of commonly used iv solutions.doc

chart of commonly transfused blood products.doc

Thank you Esme, now that makes sense! I appreciate the explanation and for the charts, I will be printing those out for work. Thanks again!

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