AKI Flashcards
What is AKI?
abrupt loss of renal function
decrease in urine volume
increase in BUN:Cr
What is oliguria?
<500cc/ day urine excretion
What is anuria?
<50cc/day urine excretion
KDIGO Criteria for AKI
-Increase in S. creatinine by >0.3 mg% within 48 hours
OR
-Increase in S. creatinine to >1.5 times baseline that occurred in last 7 days
OR
-Urine volume <0.5 cc/kg/hour for 6 hours
What are the causes of post- renal failure (azotemia)
Very common- BPH
What are the clinical findings of post-renal failure?
- Waxing and waning of urine volume
-Hematuria (normal appearing Rbcs) - Flank pain
- Anuria
- Bladder distention
- Ultrasound of kidneys often shows hydronephrosis
What are the causes of prerenal azotemia?
“decreased renal perfusion”
volume depletion
excessive intravascular volume
excessive volume outside vascular spaces
Rental artery stenosis BIL
What are the causes of acute renal parenchymal failure?
ATN d/t nephrotoxins or ischemia
What conditions respond to volume?
physiologic oliguria, pre-renal azotemia
What conditions respond to loop diuretics (but not volume)?
Incipient ATN, established ATN
Acute cortical necrosis results in _______ because it does not respond to volume or loop diuretics. It is commonly seen in ____ patients.
ESRD, younger
Pathogenesis of oliguria in ATN:
1 decreased GFR, decreased filtration s/t decreased perfusion in afferent arteriole
MOA: hemodynamic insuff= tubular ischemia + injury OR nephrotoxins (RT)
1) tubular damage with back diffusion (PCT)
2) Tubular obstruction due to debris (LoH-d)
3) interstitial edema (tissue turgor pressure- DCT)
DDx of Oliguria
Does CKD or AKI have a greater degree of hyperkalemia?
AKI
Does CKD or AKI have increased phosphorus levels?
CKD
Does CKD or AKI have hyperPTH?
CKD
Does CKD or AKI have a greater degree of anemia?
CKD
Is CKD or CKD with acute exacerbation a more rapid progression?
CKD with AE
What are the reversible factors for renal deterioration?
this is the order you should see clinically:
What is the most common drug to cause acute exacerbation of CRF or AKI?
NSAIDs
Others:
vancomycin, IV contrast, aminoglycosides, HIV drugs, acyclovir, cyclophosphamide, acetaminophen, cisplatin
If PRA due to hypovolemia, _____ _____.
Normal Saline
If PRA d/t CHF, ____ _____.
Loop diuretics
If ATN and hypovolemia, _____ _______. Why cautiously?
Normal Saline
Caution should be taken depending on the presentation of the patient. PE will help with cautious administration.
If ATN and volume replete, ____ _____.
Loop diuretics
Should you continue Lasix if no response after maxing the dose out and adding metolazone?
No
What disease are the following problems associated with?
Hyperkalemia, fluid excess, metabolic acidosis, uremia, hypertension
ATN
What are the treatments for hyperkalemia?
How does HTN affect AKI?
usually volume dependent
- Controlled with salt and water restriction and loop diuretics or RRT
- initiate/ increase antihypertensives
What factors affect the prognosis of AKI?
- severity of underlying disease
- infection
- GI heme
- surgery
- oliguria or anuria
- age
What are the 2 most common causes of death in AKI?
Septicemia (40%) and GI heme (25%)
What is the mortality rate in a hospitalized patient with AKI?
40-50%
What are the indications for Dialysis in a patient with AKI?
1) hyperkalemia
2) Pulm edema
3) Profound M. acidosis
4) uremic Si/Sx (encephalopathy, anorexia, N/V, pericardial friction rub, myoclonus or seizure)
5) prophylatic
