Flashcards in Acute Renal Failure Deck (23):
Acute renal failure? Indicator?
Abrupt decline in GFR, Indicated by increases in creatinine
Anurea? Differential diagnosis should include?
Less than 50 mL of urine output 24 hours. Acute obstruction, cortical necrosis, and vascular catastrophes (aortic dissection)
Less than 400 mL of urine output 24 hours (physiologically the lowest amount of urine person on a normal diet can make)
/fatigue, nausea/vomiting, itchiness, confusion, pericarditis due to retention waste products.
Elevated BUN without symptoms
BUN to creatinine ratio in prerenal azotemia
Causes of prerenal azotemia?
1. Volume depletion (blood loss, G.I. loss, renal loss)
2. Reduced effective blood volume (nephrotic syndrome, cirrhosis, SIRS, burns)
3. Drugs (ACE inhibitors, NSAIDs)
4. Decreased cardiac output (tamponade, CHF)
Most common causes of postrenal azotemia?
1. Prostatic obstruction
2. Uterine obstruction due to malignancy
Causes of intrinsic acute renal failure?
1. Acute tubular necrosis
3. Tubulointerstitial nephritis
Causes of acute tubular necrosis?
1. Nephrotoxic agents (aminoglycosides, radiocontrast, chemo)
2. Ischemic (hypertension, vascular catastrophe)
Causes of glomerulonephritis?
3. Immune complex diseases
4. Cholesterol emboli
Causes of tubulointerstitial nephritis?
1. Drugs (cephalosporins, methicillin, rifampin)
2. Infection (pyelonephritis, HIV)
Specific gravity and microscopic findings in:
1. Prerenal failure
2. postrenal failure
1. High specific gravity and normal microscopic findings
2. Unable to concentrate urine (isosthenuria) and various microscopic findings
Microscopic findings if postrenal azotemia is caused by:
1. Stones or crystals
2. Prosthetic hypertrophy
3. Extrinsic compression from a tumor
3. No change
Tubulointerstitial nephritis – see what in urine?
1. Mild proteinuria
2. Leukocytes and white Cell Casts
3. Urinary eosinophils
FEna<20? UA will show?
1. Prerenal failure. Concentrated urine with normal sediment
2. Early post-renal failure
FEna>1% and Una>20? UA will show?
1. ATN. Isosthenuria with muddy brown casts
2. Interstitial nephritis. Proteinuria with RBCs, WBCs and RBC casts
3. Late post renal failure. Variable.
FEna<1% and variable Una? UA will show?
Glomerulonephritis. Severe proteinuria with RBCs and RBC casts
EKG shows peaked T waves. Cause? Transient Treatment?
1. Intravenous calcium. Calcium will oppose the effects of high potassium in the heart
2. Insulin. Drives potassium into ( also can use Beta agonist like albuterol)
3. Intravenous sodium bicarbonate
Definitive treatment of hyperkalemia (as opposed to transient treatment)?
2. Kayexalate (Cationic exchange resin that exchanges Na for K in colon)
3. Emergency dialysis
Indications for dialysis?
Electrolyte disturbances (hyperK, hyperPO4)
Overload (fluid, pulmonary edema)
Uremia and Uremic pericarditis
Drugs to use in the clinical treatment of hyperkalemia?
C BIG K