Acute Kidney Injury (AKI)

Question 1

What is AKI?

Answer 1

an abrupt decline in kidney function

Question 2

Where is damage most often in AKI?

Answer 2

renal tubules

Question 3

What are 3 causes for AKI?

Answer 3

infectious agent
toxin
ischemia (decreased blood flow to kidneys)

Question 4

Examples of toxins

Answer 4

aminoglycosides
NSAIDs
IV rad contrast agents
ethylene glycol

Question 5

Examples of infectious causes

Answer 5

leptospirosis

bacterial pyelonephritis

Question 6

Examples of ischemic causes

Answer 6

heat stroke
hypovolemic shock
septic shock
severe hemorrhage
thrombus or embolism

Question 7

What is the primary pathologic change in AKI?

Answer 7

abrupt decrease in glomerular filtration

Question 8

What happens when there is a decrease in glomerular filtration?

Answer 8

• less toxins filtered from blood –> more toxins left in blood stream –> damage renal tubules –> normal secretion/absorption of electrolytes/water can’t happen
• less production of filtrate (urine)
• cellular hypoxia and damage to renal tubular cells due to lack of O2 and energy supply

Question 9

What is another cause for pathologic change that can occur within the kidney in AKI?

Answer 9

tubular obstruction

Question 10

What happens with tubular obstruction?

Answer 10

• secondary to accumulation of dead cells and debris within tubular lumen
• decreases urine production
• leads to cellular damage that further potentiates tubular dysfunction
• inability to regulate the loss of certain electrolytes and water –> unable to conserve water despite dehydration

Question 11

GI tract pathology that can result for AKI

Answer 11

toxins accumulate in bloodstream due to decreased glomerular filtration –> direct damage to GI mucosa

Gastrin (hormone responsible for acid secretion within stomach) is not filtered and excreted properly –> gastrin levels rise –> more acid gets secreted as a result –> gastric acidity increases

Both of these things lead to gastric or duodenal ulcer formation

Question 12

changes to CBC due to AKI

Answer 12

• normal
• leukocytosis if infectious agent
• moderate to severe regenerative anemia if GI ulcer with hemorrhage is present
• hemoconcentration if severe dehydration

Question 13

What’s the deal with azotemia and AKI?

Answer 13

cannot be properly evaluated unless the body’s ability to concentrate urine is evaluated at the same time, so biochem panel and UA must be obtained at the same moment in time prior to giving IV or SQ fluids

Question 14

Sudden onset of azotemia in the presence of…

Answer 14

isosthenuria (SG 1.070-1.012) OR inappropriate SG (<1.030)

Question 15

Electrolyte abnormalities seen with AKI

Answer 15

hyperphosphatemia
hyperkalemia

(kidney unable to excrete P or K)

Question 16

UA abnormalities with AKI

Answer 16

• cellular casts if renal tubular damage

- WBC and bacteria if pyelonephritis is present

Question 17

Clinical signs common with AKI

Answer 17

• sudden onset, usually within hours to days of exposure to underlying cause
• good BCS b/c sudden onset
• lethargy/weakness
• anorexia
• vomiting (fresh red blood or dark black digested blood if ulcer present)
• generally look quite ill

Question 18

List the therapeutic strategies used to treat AKI

Answer 18

• identify and eliminate underlying cause
• IVF therapy
• Peritoneal dialysis
• Hemodialysis

Question 19

If AKI underlying cause is bacteria

Answer 19

• send off urine for culture and sensitivity

- use appropriate antibiotic

Question 20

If AKI underlying cause thought to be a toxin

Answer 20

use antidote if available

Question 21

if AKI underlying cause though to be a medication

Answer 21

evaluate all meds patient is on and discontinue the med that is suspected

Question 22

Purpose of AKI IVF therapy

Answer 22

• maintain fluid, electrolyte, and pressure balance
• promotes elimination of excessive circulating toxins
• rehydrates patient
• replaces ongoing losses

Question 23

What meds may be used in addition to IVF therapy?

Hint: 3-4 types of meds are used

Answer 23

• Diuretics and/or vasodilators to attempt to increase blood flow to kidneys and subsequently increase urine flow
• antiemetics if vomiting
• H2 inhibitors to help manage the increased gastric acidity

Question 24

What is peritoneal dialysis

Answer 24

decreases circulating toxins and excessive electrolytes by drawing them into a solution that has been instilled into the abdominal cavity; solution sits in the cavity until toxins and electrolytes have had time to move from bloodstream to solution

solution is removed from the abdominal cavity via gravity and the process is repeated thru the day and night

Question 25

What is hemodialysis?

Answer 25

eliminates the toxins and excessive electrolytes in blood by removing the blood from patient and circulating it through a machine that cleanses the blood and returns it to the patient

Question 26

What nursing things are done to monitor an AKI patient?

Answer 26

• place an indwelling urinary catheter to measure the amount of urine produced to help determine how to manage fluid therapy and medical management
• monitor for overhydration by weighting q4hr and auscultation of lungs q4hr for crackle sound (pulmonary edema); also check PCV and total solids several times daily