Ep 150 Acute Kidney Injury – A Simple Emergency Approach to AKI

How comfortable are we in the ED charting anything but 'pre-renal AKI' in the patient who's creatinine surprisingly comes back sky high? Since when did the term 'multifactorial AKI' become synonymous with 'I don’t know why the creatinine is up'? Turns out those brilliant, well-rested nephrologists have been onto something all along. In this first part of our 2 part series on AKI, with the help of Dr. Edward Etchells and Dr. Bourke Tillmann (plus a bonus POCUS section with Rob Simard), we give you a simple stepwise approach to the ED assessment and management of AKI, as well as give you all the tools you need to pick up and manage rhabdomyolysis. We answer questions such as: Is there any value in the BUN:Cr ratio in distinguishing prerenal from intrarenal disease? Why is nephritic syndrome one of the most important intrarenal causes to pick up in the ED? Is there any value in urine electrolytes for the ED workup of AKI? Is there a role for bicarb in patients with severe AKI? How can we choose wisely when it comes to imaging for patients with AKI? How can we utilize POCUS best in working up the patient with AKI? What are the indications for ordering a CK to look for rhabdomyolysis? At what CK level do patients typically develop AKI? How can the McMahon score help us manage rhabdomyolysis? What is the value of urine myoglobin in the workup of rhabdomyolysis? What are indications for dialysis in patients with rhabdomyolysis? What are safe discharge criteria for patients with rhabdomyolysis? and many more...



Podcast production, sound design & editing by Anton Helman; Voice editing by Sheza Qayyum

Written Summary and blog post by Winny Li, edited by Anton Helman December, 2020.

Cite this podcast as: Helman, A. Etchells, E. Tillmann, B. Episode 150 Acute Kidney Injury - A Simple Emergency Approach to AKI. Emergency Medicine Cases. December, 2020. https://emergencymedicinecases.com/acute-kidney-injury-simple-emergency-approach-aki. Accessed [date]

Go to part 2 of this 2-part podcast on AKI

Defining AKI

The 2012 Kidney Disease - Improving Global Outcomes (KDIGO) Clinical Practice Guideline for Acute Kidney Injury (AKI) [1] defines AKI by any of the following:



* Increase in serum creatinine by ≥0.3 mg/dL (>26.5 μmol/L) within 48 hours; or





* Increase in serum creatinine to ≥1.5 times baseline, which is known or presumed to have occurred within prior 7 days; or





* Urine volume 1000, consider calcium, phosphate and VBG to estimate severity of rhabdomyolysis and their risk for requiring dialysis.

Management of rhabdomyolysis based on CK levels



* CK5000 – usually needs IV RL and admission +/- dialysis if McMahon >6



The McMahon score estimates severity and requirement for dialysis in rhabdomyolysis patients, which includes age, sex, Cr, Ca, CK, phosphate and bicarb as the score parameters [12].

Urine myoglobin has little role in the ED diagnosis of rhabdomyolysis

There is a limited role for urine myoglobin because the half-life is only 2-3hrs, so a negative result after 4-6 hrs post insult may be misleading [13,14]. In contrast, CK peaks at 24-72 hrs after the initial insult, so may be low or normal in the first few hours.

The indications for dialysis for rhabdomyolysis are the same as for any patient with AKI

Indications for dialysis in rhabdomyolysis are the same as those for any AKI patient; use the mnemonic AEIOU [15]:

Acidemia - pH