Please confirm topic selection

Are you sure you want to trigger topic in your Anconeus AI algorithm?

Updated: Nov 30 2021

Acute Kidney Injury

Images
https://upload.medbullets.com/topic/120693/images/uremicfrost.jpg
  • Snapshot
    • A 54-year-old man is admitted to the cardiac care unit after coronary angiography and revascularization secondary to unstable agina. Approximately 1 week after the procedure he is found to have a "bluish" discoloration of the first and second digits of the foot. Laboratory testing is significant for an elevated serum creatinine. A urinalysis is benign. (Renal atheroemboli)
  • summary
    • Clinical definition
      • acute reduction in glomerular filtration rate (GFR)
        • recall that GFR represents the sum of the filtration rates of nephrons
          • therefore, GFR reflects functioning renal mass
    • Pathogenesis
      • based upcome etiology (look at etiology)
  • Epidemiology
    • risk factors
      • hypertension
      • chronic kidney disease
      • dehydration and volume depletion
      • diabetes
      • chronic liver or lung disease
  • Etiology
    • prerenal causes
      • decreased renal perfusion (e.g., hemorrhage, congestive heart failure, and diuretic use)
    • intrarenal causes
      • acute tubular necrosis
        • ischemia and toxic causes
      • interstitial nephritis
      • glomerulonephritis
      • vasculitis
      • hemolytic uremic syndrome
      • cholesterol emboli
    • postrenal causes
      • urinary flow obstruction (e.g., benign prostatic hyperplasia and nephrolithiasis)
      • post-operative secondary to bladder manipulation and anesthesia
        • bladder scans should be performed followed by urinary catheterization
  • Presentation
    • Symptoms
      • may be asymptomatic
      • oliguria
      • anuria
      • polyuria
      • confusion
    • Physical exam
      • hypertension
      • edema
      • decreased urine output
  • Differential
    • Acute gastrointestinal bleeding
    • Rhabdomyolysis
    • Medication-induced impairment of creatinine secretion
      • cimetidine
      • trimethoprim
      • pyrimethamine
  • Imaging
    • Renal ultrasound
      • indication
        • initial imaging study for assessing acute kidney injury
          • can assess for renal size and hydronephrosis
          • to assess for postrenal obstruction
  • Studies
    • Labs
      • increase in serum creatinine by ≥ 0.3 mg/dL within 48 hours
      • blood urea nitrogen (BUN):creatinine ratio
      • urinalysis
        • dipstick
          • to assess for protein, glucose, leukocyte esterase, hemoglobin and myoglobin, and specific gravity
        • microscopy
          • for example
            • red dysmorphic cells suggests a glomerular etiology (e.g., glomerulonephritis)
            • muddy brown casts suggests tubular necrosis
            • white blood cell casts suggest pyelonephritis or acute interstitial nephritis
      • fractional excretion of Na+ (FeNa+)
        • if patient is on diuretics use FeUrea
      • urine osmolality and Na+
    • Studies To Assess For Prerenal, Intrarenal, and Postrenal Acute Kidney Injury (AKI)
      Studies
      Prerenal AKIIntrarenal AKI
      Postrenal AKI
      Urine osmolality (mOsm/kg)
      • > 500
      • < 350
      • < 350
      FeNa+
      • < 1%
      • > 2%
      • < 1% in mild cases
      • > 2% in severe cases
      Urine Na+(mEq/L)
      • < 20
      • > 40
      • > 40
      Serum BUN/Cr
      • > 20:1
      • < 15:1
      • Variable
  • Treatment
    • Treatment is dependent on the etiology of AKI and its consequences
      • for example
        • a patient who is hyperkalemic and not responding to medical treatment should be dialyzed
        • a patient with a history of excessive fluid loss (e.g., diarrhea and vomiting) should be given intravenous fluid
  • Complications
    • Hyperkalemia
    • Metabolic acidosis
    • Uremic encephalopathy and platelet dysfunction
    • Anemia
    • Chronic kidney disease
    • Elevated troponin
      • due to decreased renal clearance of the troponin
  • Prognosis
    • lower rates of recovery in patients > 65 years of age
    • increased risk of end-stage renal disease, chronic kidney disease, and mortality
Card
1 of 0
Question
1 of 5
Private Note

Attach Treatment Poll
Treatment poll is required to gain more useful feedback from members.
Please enter Question Text
Please enter at least 2 unique options
Please enter at least 2 unique options
Please enter at least 2 unique options