NUR 315 Exam 3

• Intrarenal


  Damage to structures within the kidney
• Prerenal

  Marked decrease in renal blood flow
• Postrenal

  Obstruction of urine outflow from the kidney after urine has been formed
• Risk factors for acute renal dysfunction

  • HTN
  • Exposure to aminoglycosides
  • Hemoglobinuria and myoglobinuria
  • Dehydration
  • Pre existing renal disease
  • Exposure to radiocontrast dyes
• Acute renal dysfunction

  • Increase in nitrogenous waste products
  • Decrease in urine output to < 1mL/lg/hr
• BUN

  • From protein in diet
  • Normal range: 8-18
  • Elevation of BUN alone doesn't always mean kidney disease
• Creatinine


  • From muscle
  • Normal range: 0.6-1.2
  • Increases when kidney function isn't good
• When is decrease in urine output especially problematic?

  
  

  if <30 mL/hr in adults
• Prerenal dysfunction

  • Any condition that directly or indirectly decreases renal perfusion
  • May be due to reduced CO or severe hypovolemia
• Intrarenal dysfunction


  • Untreated hypertension (major cause)
  • Autoimmune diseases
  • Uncontrolled diabetes
  • Direct damage to renal tissue
• Intrarenal dysfunction causes

  • Nephrotoxic meds (aminoglcosides)
  • NSAIDs like ibuprofen (damage glomerulous)
• Postrenal dysfunction

  • Obstructive uropathy preventing urine outflow from the kidney
  • Urine backs up leading to hydronephrosis
• Acute tubular necrosis

  • With ischemia, cells slough into the tubular lumen blocking it, preventing fluid to flow through the lumen reducing urine formation
  • The blocked lumen contributes to further ischemic injury of the cells lining the tubules
• Acute tubular necrosis is recoverable
• Glomerulonephritis


  • Immune complexes cause inflammation and membrane damage (commonly following beta hemolytic strep)
  • Seen 7-21 after strep infection
• Goodpatsures syndrome

  • Acute, rapidly progressive form of glomerulonephritits caused by circulating antibodies to the glomerular basement membrane (type 2 hypersensitivity)
  • Autoimmune of unknown etiology
  • T cells initiate the disorder
  • Treatment: plasmapheresis and immunosuppressants
• Nephrolithiasis


  • Formation of kidney stones
  • Dehydration major risk factor
  • Recurrence is common
• Kidney stones formed by

  • Calcium oxalate: most
  • Struvite (megnesium, ammonium, phosphate)
  • Uric acid
  • Cystine: least
• Predisposing factors for kidney stones

  • 40+ men
  • Dietary (pruines, calcium, oxalate)
  • High sodium diet
  • Gastric bypass surgery
  • Hypercalciruia, hyperparathyroidism, hyperuricemia
  • Inflammatory bowel disease
  • Dehydration (main risk)
• Pyelonephritis

  • Infection of renal pelvis and interstitum
  • Bacteria usually ascend from lower urinary tract
  • Most common cause is bacterial infection, that may result from urine reflux or obstructions (e.coli, proteus, pseudomonas)
  • Most are hospitalized
• Polycystic kidney disease

  • Most common form is autosomal dominant
  • Most common hereditary cause of renal disease
  • Also susceptible to disorder of other organs- liver, pancreas, and spleen
  • May experience heart valve problems and cerebral aneurysms
  • Defects is polycystin 1 or 2
  • Fluid filled cysts in kidneys proliferate and fibrotic changes occur
  • Progression is slow, rarely before age 40
• Chronic renal failure risk factors

  • Family history
  • AA
  • Atherosclerosis
  • Chronic glomerulonephritis
  • Diabetes
  • Hypertension
  • Nephrotoxic medications
• Renal insufficiency

  Decline in GFR to about 25% of normal
• Renal failure

  Decline in GFR to 15-20% of normal
• End-stage renal failure

  • 10% or less of normal GFR
  • Don't see symptoms until 75% of function is lost
• Chronic kidney disease (CKD)

  • CKD that has reached less that 15% of kidney function
  • Requires renal replacement therapy or kidney transplant (dialysis)
  • Symptoms: nausea, vomiting, fatigue, weakness, decreased mental sharpness, itching from urate crystals
• Renal cell carcinoma

  • 85% of all renal neoplasms
  • Associated with smoking, obesity
  • Usually caught in later stages
• Renal cell carcinoma manifestations

  • Hematuria
  • Flank pain
  • Palpable flank mass
  • Weight loss
  • Fatigue
  • Anemia
• Neuromuscular bladder control

  • Alpha adrenergic fibers relax destrusor muscle and tighten the internal sphincter
  • Stretching of bladder signals PNS to contract the detrusor muscle and relax the internal sphincter
• Bladder holds 300-400 mL of fluid
• Micturition (urination) reflex

  • Spinal cord coordinates reflex
  • Cerebral cortex can override (conscious decision to urinate)
• Obstructive uropathy

  • Kidney stones
  • Benign prostatic hypertrophy (BPH)
• UTIs

  • More in women
  • Cloudy, strong smelling urine and hematuria
  • If untreated, can lead to pylonephritis
  • Most commonly caused by E.coli (proteus, pseudomonas, streptococci, staphylococcus, klebsiella)
• Urolithiasis

  • Can be kidney stones that have moved and wedged themselves in the ureters
  • Can form in the bladder with low fluid intake, low urine production (concentrated urine can develop stones)
• Stress urinary incontinence

  With coughing or sneezing
• Urge urinary incontinence

  Overactive bladder
• Overflow urinary incontinence

  Chronic distention, BPH
• Neurogenic urinary incontinence

  Interruption of sensory nerves between bladder and spinal cord
• Functional urinary incontinence

  Caused by CNS problems such as stroke, dementia, delirium
• Bladder cancer


  • Most common type of urological cancer
  • More common in white men
  • Average diagnosis at 73
  • Related to environmental exposure (smoking, occupational)