Acute Renal Injury

Question 1

Compare acute renal injury with chronic renal disease with regards to:

permanence
onset
treatment
cause

Answer 1

acute:

• usually reversible
• fast onset (hours-days)
• may or may not require dialysis
• caused by acute injury, infection, toxins, episode of hypovolemia etc.

chronic:

• not reversible
• slow onset (months-years)
• will eventually require dialysis
• caused by chronic diseases (DM, HTN)

Question 2

What are the three categories of acute renal injury?

Answer 2

1) pre-renal
2) intra-renal
3) post-renal

Question 3

Give examples of causes for each of the three categories of acute renal injury.

Answer 3

1) pre-renal:
- hypovolemia & hypertension
(dehydration, bleeding)

2) intra-renal:
- toxic drugs
- infection
- ischemia from hypovolemia/hypotension

3) post-renal:
- BPH
- kidney stone
- tumour

Question 4

What are the phases of acute renal injury? How might treatment be different for each phase?

Answer 4

1) initiation - time of injury to time of signs and symptoms

2) oliguria and increase in metabolic waste
- key to monitor for hyperkalemia
- treatment will depend on cause, if from hypovolemia, need to give IV fluids but monitor closely for FVE because unable to produce urine

3) diuresis
- urine out put will increase as healing begins but not able to concentrate urine
- monitor for dehydration

4) recovery - can take months

Question 5

What are important care issues for someone with acute renal injury?

Answer 5

1) hyperkalemia (damaged kidney unable to excrete potassium)
2) fluid imbalance
3) azotemia/uremia
4) metabolic acidosis (accumulation of wastes and inability to excrete hydrogen or absorb bicarbonate)
5) anemia (inability to make EPO, uremia can also damage GI tract and cause bleeding)
6) dry itchy skin (from deposition of metabolic waste in skin)

Question 6

What group is at higher risk for acute renal injury and why?

Answer 6

elderly:

• more easily dehydrated
• often receiving nephrotoxic drugs

Question 7

What are symptoms of hyperkalemia?

Answer 7

• arrhythmias
• muscle weakness
• abdominal cramps
• weak, irregular pulse
• low blood pressure

Question 8

What is azotemia/uremia? What are symptoms?

Answer 8

azotemia = build up of nitrogenous waste in the blood

uremia = build up of nitrogenous waste with toxic symptoms such as cerebral irritation

• mental status changes
• pruritus
• nausea, vomiting
• fatigue
• muscle weakness
• seizure, coma

Question 9

What other fluid imbalances can occur in acute renal injury?

Answer 9

• hyponatremia if free loss of water (seizures, muscle twitching)
• increased phosphorous
• low calcium (kidney activates vitamin D, which is needed for calcium absorption)

Question 10

What are nursing interventions for a patient with acute renal injury?

Answer 10

• apply oxygen to decrease kidney ischemia
• encourage/give fluids and monitor fluid status
• change diet to decrease kidney workload (high carb, low protein, low potassium)
• provide skin care
• encourage rest (to decrease metabolism and therefore amount of waste kidney burdened with)

Question 11

What are some medications that can be used in the treatment of acute renal injury?

Answer 11

• IV fluids
• IV insulin and glucose, or calcium gluconate (will temporarily shift potassium back into cells)
• Kayexalate (PO or enema, exchanges sodium for potassium in GI tract)
• sodium bicarbonate (corrects acidosis, which will prevent movement of potassium out of cells)
• diuretic may be used to increase urine production (prevent water retention) during oliguric phase

Question 12

What diagnostic tests are helpful in acute renal injury?

Answer 12

• increased BUN
• increased creatinine
• urinalysis and C&S, will show damage, to find cause (ex. proteinuria, infection, DM)
• decreased GFR
• imaging (stone?)