why give this patient magnesium sulfate??

[mb2995]

Hi Patient had hip surgery and wound up with c diff. Post surgery hemoglobin and hmeatocrit are low but were not prior to surgery. Potassium is low, calcium low, chloride high.Patient has no mag levels recorded. GFR and creatinine within normal limits Patient takes beta blocker at night exteneded release. only other meds are vitamins Provider ordered mag sulfate Any ideas as to why? thanks! 1 gram in 100 mls IVPB and primary 1000 mls of K/CL 60 mls/hour

[mluvsgnc]

Maybe to offset the hypocalcemia and hypokalemia and prevent tetany (which comes with low Mg and low Ca)? I would want a Mg level on this patient- seems weird to give it without knowing baseline.

[NickiLaughs, ADN, BSN, RN]

If you need to replace Mag and K, you do Mag first to help promote K repletion as well. However, doesn't make sense without a mag level?

[K+MgSO4, BSN]

If you need to replace Mag and K you do Mag first to help promote K repletion as well. However, doesn't make sense without a mag level?[/quote']

Yup. What she said. Also if someone is having frequent liquid bowel actions their gut is not getting a chance to absorb electrolytes from food.

[doho_rn, ADN, RN]

could it have been ordered by mistake and the dr meant to order K+

[morte, LPN, LVN]

serum Mag is not particularly helpful, need a cellular level test. Perhaps that would take too long? I also understand most healthy persons in this country (USA) are mag def any way...

If you need to replace Mag and K, you do Mag first to help promote K repletion as well. However, doesn't make sense without a mag level?

[lwhatley]

I'll take a shot at this one:

Pt has C-diff (excessive diarrhea), and labs reveal an already low K+, which is something that you'd already be identifying as a potential side effect to this patho anyway. I'm not sure how long this patient has been c-diff symptomatic, but if it's still relatively early, labs revealing already low K+ lvls essentially mean this pt left the starting line of c-diff at a disadvantage...

K+ supp is a given, given that you've not only already ID'ed the expected side effect of c-diff causing low K, but you've additionally run labs either confirming c-diff induced decrease in K has occurred, or were present prior to cdif arrival...so what now?

Again, if we're still only in early C-diff presentation, we gotta correct K+, and we gotta correct it fast or we know our pt's about to tip that K+ scale upside down and get critical.

So how to we ensure optimal ability for our pt to correct K+? Mag.

K+ won't play ball until Mag's already on base; and again, let's say we're pessimists and we're assuming this pt might have had a problem with K+ before he started losing it out of his butt from C-diff...then we have to try and work backwards and target a likely cause just to cover our bases, which would be that pesky Mag love K+ has.

People above have also made an excellent point that throwing Mag at a sick colon sounds silly because absorption is already going to be compromised, but think of this method of Mag supp more like "Throwing spaghetti at a wall and seeing what sticks", sure he'll probably leak more mag than he'll absorb, but at least some might slip through the cracks. There are very real safety risks that are involved with this drug, but this doctor should be weighing his risk/benefits...and pt's meds (BB) already kinda hint that his heart might not be able to handle a critically low potassium lvl in the future, and he's already cross checked to make sure that the kidneys would be able to handle the mag doses...so I would personally back the doc up on this one.

[Helori]

Was the pt on tele? Because in our CCU when we have a pt having a lot of runs of VT we often give 1g of Mag even with out a previous level. On VTers out docs like levels better than 1 and I've never seen that on a pt who hasn't had Mg replacement. So even if they have a 'normal' level previously we replace. It really works wonders!!

[Anna Flaxis, BSN, RN]

Hypokalemia is associated with hympomagnesemia about 50% of the time, and judging from the low K+ and Ca and elevated Chloride, it's a safe bet that this patient has low magnesium levels, most likely r/t the diarrhea, as well. Also, low Mag can make low K+ and Ca refractory to treatment, so best to replace it so the others can be corrected as well.