Acute Kidney Injury & Chronic Kidney Disease (Ch. 34)-- Term First

Question 1

Intrarenal AKI

Answer 1

• Structural damage within kidney
  
  • Glomeruli
  • Vessels
  • Tubules
  • Interstitium
• Sudden ⇣ in renal blood flow → Acute tubular necrosis
  
  • Prerenal injury
  • Intratubular obstruction
  • Acute renal disease
  • Drug nephrotoxicity
  • Toxins from infections

Question 2

Intrarenal AKI Clinical Manifestations

Answer 2

• Initiation
  
  • No S/S for hrs. or days
  • ⇣ GFR
  • ⇡ BUN
• Maintenance
  
  • 1-2 weeks
  • Oliguria + ⇣ GFR
    
    • <20 mL/hr
  • Metabolic waste accumulation
    
    • Edema
    • Pulmonary congestion
    • HTN
    • Uremia
• Recovery
  
  • Repair of renal tissue
  • Excessive diuresis
    
    • 1-2 L/day
    • First sign
  • ⇡ GFR & urinary output
  • ⇣ SCr & BUN

Question 3

Prerenal AKI

Answer 3

• Most common
  
  • 25-80% mortality rate
• Sudden ⇣ in renal blood flow → Ischemic tubular necrosis
  
  • ⇣ GFR (<25% of normal)
    
    • Normal GFR: 120-130 mL/min
  • Sharp ⇣ urine output
    
    • Acute, early sign
  • ⇡ BUN : SCr
    
    • 10:1 (normal) → 20:1 (elevated)

Question 4

CKD Metabolism Manifestations

Answer 4

• Kidneys unable to excrete phosphorus
  
  • ⇡ Phosphorus & ⇣ Ca²⁺ → ⇡ PTH → ⇡ Ca²⁺ resorption from bone
• Impaired Vit. D Synthesis
  
  • ⇣ Vit. D → ⇡ PTH & ⇣ Ca²⁺ intestinal absorption
    
    • Osteoporosis
    • Osteomalacia
    • ⇡ Fracture risk
• Protein, CHO, & Fat metabolic changes
  
  • ⇣ Serum protein → ⇣ Muscle mass & ⇣ Colloidal osmotic pressure → Edema
  • Insulin resistance & glucose intolerance → DM
  • Dyslipidemia

Question 5

CKD Fluid & Electrolyte Manifestations

Answer 5

• Loss of ability to regulate Na⁺
  
  • Early CKD: Na⁺ & H₂O loss
  • Late CKD: Na⁺ & H₂O retention → Edema & HTN
• 90% of K+ renally eliminated
  
  • ⇡ Hyperkalemia risk → Dysrhythmias
    
    • Dialysis (@ least 4 hrs.)
• ⇣ Ability to eliminate H⁺ & resorb HCO₃^-
  
  • Metabolic acidosis

Question 6

Chronic Kidney Disease (CKD)

Answer 6

End result of kidney damage, develops slowly– IRREPARABLE

Question 7

CKD Cardiovascular Manifestations

Answer 7

• ⇡ Morbidity (illness) and mortality (death)
  
  • 10-20X higher
• ⇡ Blood volume → HTN
• Dyslipidemia → Vascular disease
  
  • Ischemic heart disease
  • HF
  • Stroke
  • Peripheral vascular disease

Question 8

CKD Hematologic Manifestations

Answer 8

• Anemia
  
  • ⇣ Erythropoiesis → Iron deficiency & ⇣ RBCs
    
    • Weakness, fatigue, HA, irritability, depression, insomnia, ⇣ cognitive function
  • ⇣ Blood viscosity → ⇡ HR & Peripheral vasodilation
  • ⇣ Myocardial O₂ → Angina, ischemic cardiac events
• Dialysis damages platelets
  
  • ⇣ or impaired platelets → bleeding
  • ⇡ Risk of thrombotic disorders

Question 9

Renal Failure

Answer 9

• Kidneys fail to
  
  • Remove metabolic waste from the blood
  • Regulate fluid, electrolyte, & pH balance of ECF
• Loss of endocrine function
  
  • Renin
  • Erythropoietin

Question 10

Postrenal AKI

Answer 10

• Bilateral urinary tract obstruction
  
  • Ureter
  • Bladder
  • Urethra
• Retrograde pressure
  
  • Glomeruli
  • Tubules
  • Nephron
• BPH– most common cause

Question 11

CKD Pulmonary Manifestations

Answer 11

• ⇡ Blood volume → Pulmonary edema & HTN
• Kussmaul respirations
  
  • Hyperventilation
  • Compensatory mechanism for metabolic acidosis

Question 12

Types of Acute Kidney Injury (AKI)

Answer 12

• Prerenal
  
  • ⇣ Blood flow to and through kidneys
• Intrarenal
  
  • Structural damage
• Postrenal
  
  • Obstruction to urine outflow
    
    • BPH (most common)

Question 13

Acute Kidney Injury (AKI)

Answer 13

Abrupt injury to the kidneys, w/i 48 hrs.– REVERSIBLE (if treated early)

Question 14

Chronic Kidney Disease Management

Answer 14

• Dietary restrictions
  
  • ⇣ Protein, Na⁺, K⁺ & Phosphate
  • Vit. D supplementation
  • Fluid balance/restriction
  • Glucose control (DM)
• Medications
  
  • ACE-Is & ARBs
    
    • Dilate efferent arteriole
• End-stage renal failure
  
  • Renal replacement therapy
    
    • Peritoneal dialysis
    • Hemodialysis
  • Kidney transplant

Question 15

Prerenal AKI Causes

Answer 15

• Shock
  
  • Hypovolemia
• HF w/ ⇣ CO
• Intrarenal vasoconstriction
  
  • Contrast media
  • Cyclosporine
  • NSAIDS

Question 16

Other CKD Manifestations

Answer 16

• Altered immune function
  
  • ⇡ Infection risk
• Altered CNS & PNS Function
  
  • Peripheral neuropathy
  • Restless leg syndrome
  • Uremic encephalopathy
• Sexual dysfunction
  
  • Impotence
  • Hypofertility
  • Dysmenorrhea
• Disorders of skin integrity
  
  • Pale, sallow, grey skin
  • Dry/scaly skin and mucous membranes
  • Bruising

Question 17

Chronic Kidney Disease (CKD) Clinical Manifestations

Answer 17

Multiple systemic effects related to loss of GFR and endocrine functions

• ⇣ Kidney function
  
  • ⇣ GFR
    
    • <60 mL/min for 3 months +
  • ⇣ Ion, electrolyte, and H₂O resorption
  • ⇣ Endocrine functions
• Azotemia (nitrogenous waste in blood)
  
  • ⇡ BUN & ⇡ SCr
• Uremia (urine in blood)
  
  • ⅔ of Nephrons destroyed
  • Uremic encephalopathy
    
    • Pruritis
    • N/V
    • Weakness/fatigue
  • ⇡ BP
  • ⇣ Erythropoiesis
  • Impaired Vit. D synthesis