AKI, Acid/Base

Question 1

Buzzword: “Muddy brown casts on UA”. Dx?

Answer 1

ATN

Question 2

Urine studies of ATN? Specifically, urine Na & FeNa?

Answer 2

Urine Na > 20. FeNa > 1%.

Question 3

Difference in physiology between pre-renal AKI and ATN?

Answer 3

In ATN, the kidney is damaged and UNABLE to retain Na, causing high urinary sodium.

Question 4

Name of FDA-Approved biomarker of risk of AKI?

Answer 4

NephroCheck. Contains TIMP-2 & IGFBP-7.

Question 5

RBCs in casts in UA indicates problem where (anatomically)?

Answer 5

Glomerulous. Glomerulonephritis, e.g.

Question 6

RBCs in UA that are free floating (not in casts) indicates problem is where (anatomically)?

Answer 6

Below the kidneys, in the GU system.

Question 7

Cutoff of FeUrea?

Answer 7

30%

Question 8

Types of hepatorenal syndrome?

Answer 8

I: rapid.
II: assoc w/ diuretic resistant ascites.

Question 9

FeNa of Contrast-Induced-Nephropathy?

Answer 9

FeNa < 1%

Question 10

In SMART & SALTED trials, LR improved outcomes with over NS. What subgroup drives this outcome?

Answer 10

septic

Question 11

When doing acid/base calculations, using the old method of bicarb & anion gap, it is important to remember what correction?

Answer 11

Correct AG for hypoalbumenmia.

Question 12

Equation to correct anion gap for hypoalbumenmia?

Answer 12

AG increases by 2.5 for every 1g/dL of hypoalbumemia.

Question 13

Winter’s formula?

Answer 13

Expected PaCo2 = 1.5*HCO3 + 8 +/-2

Question 14

Equation for expected PaCO2 in response to metabolic alkalosis?

Answer 14

Expected PaCO2 = 0.9*HCO3 +15 +/-5

Question 15

How to find expected metabolic compensations due to primary respiratory problems? Easy mnemonic.

Answer 15

For every change of 10 PaCO2, the HCO3 will change by (1,2,4,5) in response to a (Acute/Chronic Respiratory Acidosis/Alkalosis - in alphabetical order).

Question 16

Lab value to indicate that a metabolic alkalosis is chloride-responsive?

Answer 16

Urinary chloride < 10

Question 17

Ddx of chlorine-responsive metabolic alkalosis? (4)

Answer 17

Vomiting, NG suction, diuresis, post-hypercapnea

Question 18

Components of MUDPILES mnemonic for HAGMA?

Answer 18

• Methanol.
• Uremia.
• DKA.
• Paralydehyde.
• Iron, INH.
• Lactate.
• Ethylene Glycol.
• Salicylates.

Question 19

Components of HARDUP menmonic for NAGMA?

Answer 19

• Hyperalimentation.
• Acetazolamide.
• RTA.
• Diarrhea.
• Uretero-bowel fistulas.
• Pancreatic fistula, post-hypervention

Question 20

Equation for renal anion gap?

Answer 20

UrNa + UrK - UrCl

Question 21

Normal Urinary anion gap?

Answer 21

+/-10

Question 22

In setting of metabolic acidosis, what does high urinary anion gap mean? Low UrAG?

Answer 22

High = kidney problem. Low = not kidney problem.

Question 23

3 causes of low anion gap?

Answer 23

• High K, Mg, Ca.
• Li.
• Paraproteins / multiple myeloma.