Renally dosing for AKI

[Redpancreas]

I have heard some hospitalists and a few nephrologists mention treating an AKI as if CrCl<10 for medications that aren’t directly nephrotoxic, but are renally cleared (ex. Colchicine, Remdesivir, etc.) but don’t know how widespread that practice is.

1.) Does your institution do that?
2.) What’s the evidence or physiological basis for that or is this just dogma that developed out of habit?

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[chessknt]

I think the issue is you don't always clearly know the trajectory of an AKI so if you assume the worst you won't accidentally over-do it. I typically defer all this to pharmacy since that is their area (ironically not nephrology though they certainly have plenty of experience) but if you wanted to be involved on a more granular level I would advocate for not doing this on drugs that are critical for patient recovery (eg antibiotics)

 

[Chemist0157]

I have heard some hospitalists and a few nephrologists mention treating an AKI as if CrCl<10 for medications that aren’t directly nephrotoxic, but are renally cleared (ex. Colchicine, Remdesivir, etc.) but don’t know how widespread that practice is.

1.) Does your institution do that?
2.) What’s the evidence or physiological basis for that or is this just dogma that developed out of habit?

I honestly do not really bother including things like that in my note. Someone consulted me for AKI so he or she should know the patient has AKI. Pharmacy manages a lot of the dosing anyway, and my addition in a note probably is not going to make any difference if the other doc is not paying attention. I look at medications myself and make sure things look okay. I believe their is a pharmacy consult order that can be placed specifically for them to review medications for renal dosing.

The thought behind that would be, as above, one may not know where the renal impairment is going to settle because remember, the creatinine is lagging behind the actual injury. When you see creatinine creep up every day, the kidneys may not be getting worse every day (unless urine output is declining steadily too) but just approaching a plateau that represents the current kidney function. Maybe that creatinine level is 2. Maybe it is 10.

 

[Redpancreas]

Both these answers make sense. At our institution, there was an order only for Vanc and then everything else we dosed ourself BUT there was an inpatient pharmacist assigned to every medicine team who called us if there was anything wrong.

I guess estimating creatinine clearance <10 is basically assuming the kidneys aren’t working (ie dialysis dosing) in order to be conservative.

I completely agree with the Chessknt about the antibiotics. So many times we get hung up about antibiotic induced kidney injury in the ICU when it’s more likely related to ATN from septic shock.
I guess estimating creatinine clearance <10 is basically assuming the kidneys aren’t working (ie dialysis dosing) in order to be conservative and when to be conservative should depend.

 

[Make Or Break]

Both these answers make sense. At our institution, there was an order only for Vanc and then everything else we dosed ourself BUT there was an inpatient pharmacist assigned to every medicine team who called us if there was anything wrong.

I guess estimating creatinine clearance <10 is basically assuming the kidneys aren’t working (ie dialysis dosing) in order to be conservative.

I completely agree with the Chessknt about the antibiotics. So many times we get hung up about antibiotic induced kidney injury in the ICU when it’s more likely related to ATN from septic shock.
I guess estimating creatinine clearance <10 is basically assuming the kidneys aren’t working (ie dialysis dosing) in order to be conservative and when to be conservative should depend.

If the kidneys are not filtering out the abx for whatever reason then there’s no point to give more.

 

[Meerkatology]

my personal take is that if u have a creatinine of 2 during AKI. its u are likely functioning lower than a creatinine of 2 in CKD.
it takes time ur creatinine to go up, if it was 0.5 yesterday and they surgically removed both of ur kidneys this morning. ur Cr isnt going to jump right away into ESRD levels. its going to slowly go up.

so you dont truly know what % ur kidney is functioning at based on the creatnine during AKI, so u assume its worse than a same Cr during ckd..