Some questions about gentamicin...

[summerlove2]

I am a new NICU nurse in a Level IIB nursery... I am very curious as to what other units do in regards to IV medications. We retrograde nearly all of our medications, but from what I hear this is relatively rare and syringe pumps are more popular. I am wondering what your unit does and why.

My real question though is about gentamicin.

- How often do your docs/NPs order it... I see quite alot who order every 12 hours, but also have seen 18 and 24 (and even less often if renal function is poor).

-What would be the rationale of starting at say every 24 hours vs. every 18 hours when first ordering (no renal function tests done yet).

-What is the dose usually ordered... I've seen everything from 2.6 mg/kg/day up to 6 mg/kg/day on my search on the internet. Any fairly standard dose?

- It seems pretty standard to give it over 1/2 hour, but how much do you dilute it too (our very handy IV administration manual at work, which is used on all units, adults/kids/neonates, states dilute to a concentration of 1-10 mg/mL...)

Any answers would be really appreciated!!

[babyNP., APRN]

Our doc's go by the NeoFax, the pharm book specifically meant for neonates and follow its recommendations. Our pharmacy also does all the diluting for us (only unstable drugs we dilute like ampicillin, indocin, etc).

[Love_2_Learn]

We use the Neofax as well. You can order one online from Amazon which is where I get mine. There is usually a new one published each year. When you look up gentamicin in there you will see that it gives dosages and times based on baby's birth weight and age. We usually start with q 24 hr dosing, get a peak and trough level around the third dose, then if the results are out of whack the doctor or nurse practitioner will order the dose to be given at a different interval of time. They usually keep the same dose but change how often it is administered. They will check a level again when they make these types of changes. Our pharmacy mixes up our doses in a 5mg/ml dilution. If the pharmacy is closed we mix it up ourselves. We use the 20mg/2ml pediatric vial and draw up 2 ml of it and place it in a 10 ml syringe, then with another needle and syringe draw up 2 ml of sterile water and add that to the 10 ml syringe that has the gentamicin in it. The 10ml syringe now has 20 mg of gentamicin in a total of 4 ml fluid which we shake up really well. This is now a 5 mg/ml dilution (20mg divided by 4ml = 5mg/ml). we draw up the dose from this 10ml syringe. Diluting it makes the dose more accurate especially with the smaller babies and also is less caustic on their veins. We give it over 30 minutes on a syringe pump. Often when we have micropreemies we do not use gentamicin but use claforan instead of gent. since it is less stressful on the kidneys. Hope this helps you out a bit. I've learned about the retrograde administration of medications but have never actually worked anywhere that administered medications that way. Where I have worked they always used syringe pumps.

[NicuGal, MSN, RN]

We also use the Neofax. Gent is given according to post conceptual age and weight. We will push the first dose and then give on a syringe pump over 1/2 hours for subsequent doses. I haven't retrograded a med in about 20 years! Does your unit have a med guideline book?

[heymama1plus1]

I've been around awhile and I gotta ask... what is retrograding a med? Is it something normally done on adults (I've only done NICU)?

[SteveNNP, MSN, NP]

Dosing gentamicin depends on gestational age at birth, plus postnatal days of life. Sometimes doses are adjusted based on levels, renal function, etc. Our standard gent doses are from 4-5 mg/kg q 24-48 hours based on the above information.

We only substitute cefotaxime (3rd gen cephalosporin) if we suspect meningitis, as cef crosses the blood brain barrier easily, and if renal failure exists, and we are forced to treat an infection. 3rd generation cephalosporin use drastically increases the risk of fungal superinfections, which because we use them sparingly here... rarely occur in our unit.

Our pharmacy dilutes to 5mg/ml, and we infuse via syringe pump over 30 min. I have never seen or done a retrograde infusion.

[dawnebeth]

We never retrograde anything in the ICN, although they do on the floors, which always confuses us nursery nurses when we float. We use syringe pumps exclusively and give gent over half an hour

All Gent doses are mixed by the pharmacy, but as far as I know the dosage intervals are decided by the gestational age and weight of the baby. Smaller preemies get 24 hours, larger ones q12. With blood levels done at the fifth dose on q24 and the third dose on q12 dosing.

[summerlove2]

Thanks everyone for your answers... in answer to a couple of your questions...

1) No we do not have a IV/med administration book specific to the NICU. We use the general manual used by the entire hospital... therefore the confusion when using the manual and sometimes it prescribes a medication to be diluted in 100 mL NS. We have a Neonatal Medication book published in like 1992 or so... but not sure if I would want to hang my license on something nearly 20 years old (and its not policy). I did go on the Neofax website and it looks like something the unit could definitely use!! Looks quite pricy... is it available as a book at all or is it only digital?

2) Retrograding a med... I believe this is very old school and our unit is talking about switching over to syringe pumps but alot of the senior staff will only retrograde. What it involves:

a) clamp off the IV tubing closest to the baby (so the med won't get pushed)

b) locate two IV ports; in the port most proximal to the baby insert the syringe that has the medication in it (should be less than 3cc total volume), in the other port, distal to the baby insert an empty syringe

c) push the contents of the medication syringe into the IV tubing, as the IV is clamped off lower down, the medication will go into the IV tubing and the solution that was in the IV tubing will be displaced into the empty syringe. So there will be a stretch of the IV tubing that will have a med in it.

d) Adjust flow rate of the IV so that the medication will be infused in the proper amount of time... hope this makes sense!

As far as I know this is mostly used in the neonatal and peds worlds, mostly because only such a small amount of med can be retrograded (it HAS to fit in the space between the two ports, else it is not an accurate dose).

[ittybabyRN, RN]

summerlove2 said:

Thanks everyone for your answers... in answer to a couple of your questions...

1) No we do not have a IV/med administration book specific to the NICU. We use the general manual used by the entire hospital... therefore the confusion when using the manual and sometimes it prescribes a medication to be diluted in 100 mL NS. We have a Neonatal Medication book published in like 1992 or so... but not sure if I would want to hang my license on something nearly 20 years old (and its not policy). I did go on the Neofax website and it looks like something the unit could definitely use!! Looks quite pricy... is it available as a book at all or is it only digital?

2) Retrograding a med... I believe this is very old school and our unit is talking about switching over to syringe pumps but alot of the senior staff will only retrograde. What it involves:

a) clamp off the IV tubing closest to the baby (so the med won't get pushed)

b) locate two IV ports; in the port most proximal to the baby insert the syringe that has the medication in it (should be less than 3cc total volume), in the other port, distal to the baby insert an empty syringe

c) push the contents of the medication syringe into the IV tubing, as the IV is clamped off lower down, the medication will go into the IV tubing and the solution that was in the IV tubing will be displaced into the empty syringe. So there will be a stretch of the IV tubing that will have a med in it.

d) Adjust flow rate of the IV so that the medication will be infused in the proper amount of time... hope this makes sense!

As far as I know this is mostly used in the neonatal and peds worlds, mostly because only such a small amount of med can be retrograded (it HAS to fit in the space between the two ports, else it is not an accurate dose).

Oh my gosh! that sounds like such a process! Syringe pumps are so much easier, just have a dedicated med line that you can hook your syringe right too and run over the pump, run a flush after it and you're done, no calculations, no changing drips etc. Also the neofax is a book and can be purchased at Amazon.com and I'm sure other places, we have one at every med station and most nurses carry their own as well just in case

[summerlove2]

Just looked at the Neofax book on Amazon and it looks wonderful!! And only $40, don't understand why the unit doesn't own one but will definitely buy one. It looks like the new edition will come out in June so will probably buy then... Thanks so much for this suggestion!!!

[littleneoRN]

We use pumps for everything and I had not heard of retrograding before this...

Our standard is for gentamicin to be ordered q24h. Micros usually start with q36h or q48h. Levels are checked for anyone continuing longer than a 48 hour rule out.

We always give 4 mg/kg/dose unless there is a unique situation. Ours are generally diluted to 3 mL. Always given over a half hour. We never push gentamicin. (Well, never say never...)

[psychonaut]

A related Neofax note, Similac reps have access to free PDA versions that last a year (literally lock up after a year, cannot even be accessed anymore).