Acute Kidney Injury I and II

Question 1

T/F usually there are a lot of symptoms of AKI

Answer 1

false. usually they first do not have symptoms. History is crucial but not sensitive or specific

Question 2

Diagnosed through ____ ___

Investigate patients with diseases or symptoms that cause AKI

Answer 2

Diagnosed through laboratory measurements Investigate patients with diseases or symptoms that cause AKI

Question 3

Diagnosing Definition of AKI

Answer 3

1. less than 7 days; over hours to days.
2. rise of creatinine of 26.5 umol/L OR
3. rise of creatining to 1.5x baselines OR
4. or less than 0.5ml/kg/hr for 6 hours

Question 4

general causes of AKI

Answer 4

vomiting, CHF, infection, pr autoimmune conditions

Question 5

T/F eGFR is beneficial in diagnosing AKI

Answer 5

false. It’s just an estimate that assumes that creatinine is stable. in AKI, creatinine may not be stable and eGFR calculations are wrong.

Question 6

Fill out AKI staging table

Answer 6

Question 7

Natural history of AKI:

10 – 15% chance of __

___ increases chance of surviving to 40-60%
Survivors are at risk of ___ and __

Answer 7

10 – 15% chance of dying

Dialysis increases chance to 40-60%
Survivors are at risk of CKD and hypertension

Question 8

ultimate pre-renal cause of AKI

Answer 8

decreased perfusion of the kidneys

Question 9

ultiamate renal cause of AKI

Answer 9

injury to the kidney parenchyma

Question 10

ultimate post-renal cause of AKI

Answer 10

blockage of urine outflow

Question 11

pre-renal cause of AKI (that lead to reduced blood flow to kidneys) can be due to: (3)

Answer 11

Any disease state that lowers blood flow to the kdineys can cause an injury, they are separated into different categories:

hypovolemia (GI bleed), distributive shock (septic shock), cardiogenic shock (CHF).

Question 12

signs that can help lead you to diagnose PRE-renal AKI

Answer 12

• look for signs that indicate reduced blood flow or poor perfusion. The kidneys are holding onto salt to keep water.

- random urine sodium less than 20 mmol/L

- fractional excretion of sodium FeNa than 1%

Question 13

FeNa equation and what it means

Answer 13

FeNa<1% indicates that kidneys are underperfused. The body is doing anything it can to hold onto sodium. Measure of the percentatge of sodium that the body is wasting, compared to the amount of creatinine being filtered.

Note that low urine sodium is not exclusing to pre-renal AKI. it can also be due to renal and post- renal causes due to low EABV. Rule out with urinalysis and microscopy, and ultrasound KUB

Question 14

Note that low urine sodium is not exclusing to pre-renal AKI. it can also be due to renal and post- renal causes due to low __. Rule out with ___ and __, and ultrasound ___

Answer 14

Note that low urine sodium is not exclusing to pre-renal AKI. it can also be due to renal and post- renal causes due to low EABV. Rule out with urinalysis and microscopy, and ultrasound KUB

Question 15

Question 16

Post renal (blocked outflow to the kidneys). As more urine enters the urinary tract, the pressure builds due to the blockage. the pressure rises to the point where it rises to the kidenys. pressure leads to kidney damage. 
What are some diseases that can result in blockage of the urinary tract?

Answer 16

males: prostatic hypertropy, prostate cnacer

Both sexes; kidney stones, developmental anomalies, cancers, retroperitoneal fibrosis (where lining of the abdomen gets fibrotic and compresses the kidneys)

Question 17

signs of prostatic hypertrophy

Answer 17

hesitancy, low flow, frequent urination, nocturia

Question 18

signs of kideny stones

Answer 18

flank pain

Question 19

signs of cancer causing AKI

Answer 19

constitutional symptoms, hematuria

Question 20

ultrasound indications of blocked UT

Answer 20

1. hydronephrosis (due to blocked ureteres)
2. kidney stones (mechanical block)
3. bladder masses

Question 21

foley catheterization can used in diagnosing and treatment of urinary tract obstruction. how?

Answer 21

when you put the catheter in, a large amount of urine released may indicate an obstruction and treat the condition/symptoms of pressure

Question 22

In renal, the injury is happening to the kidney parenchyma itself. there are four parts of the parenchyma:

Answer 22

1. glomeruli
2. tubules
3. microvasculature
4. interstitium

Question 23

glomeruli renal injury; damaged filers causing AKI. What components of urine would indicate damaged glomeruli?

Answer 23

dysmorphic red blood cells,

red blood cell casts

proteinuria

Question 24

MAID acroncym for causes of glomerular renal injury resulting in AKI

Answer 24

M: malignancy

A: Autoimmune

I: infection

D: drugs

Question 25

Acute tubular necrosis (ATN)- the tuubles draining the glomeruli are damaged to the point that they die. This causes an acute kidney injury. there are two main causes of ATN:

Answer 25

1. ischemic; tubules not getting enough blood and die from hypoxia
2. toxins.

Question 26

Diagnosing ATN via Lab findings and microscopy

Answer 26

when tuublar cells die, they fall into the lumen of the tubule. they get trapped and form a casting of the tubule cell. there are lots of granules in the tubular cells and thus their casts look granular. depending on the scope, they may have a muddy brown color.

- FeNa greater than 2%. Tubular cells are not working properly. thirsty kidneys do everything they can be reabsorbing salt then water. if they have a low EABV, urine Na is low. if tubular cells are low, they cannot reabsorb sodium. therefore if someone has a low EABV and their fractional excretion of sodium is greater than 2%, the tubular cells are not working.

Question 27

interstitial nephritis – 4 big causes

Answer 27

inflammation of kidney interstitium. Caused by

1. antibiotics
2. NSAIDS
3. Autoimmune conditions
4. Infections; WBC flood into interstitium, causing damage.

Question 28

classic lab clue that will indicate interstitial nephritis (renal cause of AKI)

Answer 28

WHITE BLOOD CELL CASTS are pathognmonic. some WBCs that cause the inflammation move throuhg the tubules and get trapped in the proteins, coming out as white cell casts.

Question 29

in vascular cases of renal AKI, we refer to ___ vasculature of kidneys, not the renal arteries. caused by the same things that cause __ __ __ (__)

Answer 29

in vascular cases of renal AKI, we refer to microscopic vasculature of kidneys, not the renal arteries. Its caused by the same things that cause microangiopathic hemolytic anemia (MAHA)

• TTP and HUS (ecoli)
• microthrombi form in the small vasculature of the organs, causing ischemia that ultimately lead to AKI

Question 30

biggest clues that can indicate a vascular cause of AKI (renal)

Answer 30

recall that vascular renal AKI is caused by similar things that cause MAHA (TTP/HUS).

-therefore, the clues are MAHA findings, like thrombocytopenia, hemolysis and schistocytes

Question 31

summary;

Answer 31