Lecture 5: Acute Kidney Injury Flashcards
In a patient with AKI/ARF a hx of what serum measurement should be obtained?
Most recent serum creatinine baseline and preferably one 3 months before acute event
What are 5 factors which can alter serum creatinine?
- Age
- Sex
- Race
- Muscle mass
- Catabolic rate
Impaired renal autoregulation may be due to what drugs and is considered what type of cause for AKI (pre-, post- or intrinsic)?
- NSAIDs, ACE-I/ARBs, Cyclosporins
- Pre-renal cause
What are 4 sources of endogenous nephrotoxins implicated in AKI?
- Hemolysis
- Rhabdomyolysis
- Myeloma
- Intratubular crystals
What are 4 of the main tubulointerstitial causes of AKI?
- Ischemia
- Sepsis/infection
- Exogenous nephrotoxins
- Endogenous nephrotoxins
List 5 exogenous causes of tubulointerstital AKI?
- Iodinated contrast
- Aminoglycosides, amphotericin B
- Cisplatin
- PPI’s
- NSAIDs
2 major post-renal causes of AKI?
- Bladder outlet obstruction
- Bilateral pelvoureteral obstruction
What must you be sure to ask pt about in regards to history when presenting with signs/sx’s of AKI?
- Be sure to ask about all meds including OTC’s and herbals/supplements
- Toxin exposures –> work/home/hobby
What urine and serum values can be used to determine pre-, post- and intrinsic causes of AKI?
- Serum sodium (Na) and creatinine (Cr)
- Urine sodium (Na) and creatinine (Cr)
- Allows you to calculate fractional excretion of Na (FENa)
How does the value of FENa differ between pre-renal and intrinsic renal causes of AKI?
- Pre-renal = <1 —> decreased renal perfusion w/ increased reabsorption of Na
- Intrinsic renal = >1 –> damage to tubules = salt wasting
Key diagnostic tool for postrenal AKI?
Ultrasound
Important diagnostic studies that should be done on someone with AKI?
- Ultrasound
- EKG
Treatment for pre-renal cause of AKI is focused on what?
- Remove/treat underlying contributing factots
- Stop likely med offenders = NSAIDs, Cyclosporine, ACE-I/ARBs
Treatment approach for post-renal causes of AKI?
- Drain urinary bladder –> retention cathetrs or repeat catheterization
- Eliminate obstructions –> retrieve/pass stones, reduce prostate size, ureterostomy or nephrostomy stents to avoid hydronephrosis
The treatment for intrinsic causes of AKI is focused on improving renal perfusion, what are 3 focuses of this treatment?
- Optimize cardiac output
- Minimize 3rd spacing of fluids
- Give fluids (normal saline)
