Anion Gap

Question 1

Anion Gap Formula

Answer 1

(Na +K) - (Cl + HCO3)= Anion Gap = UA - UC

Question 2

Unmeasured Cations (2)

Answer 2

1. Ca

2. Mg

Question 3

Unmeasured Anions (5)

Answer 3

1. Albumin
2. Ketones
3. Lactate
4. Sulfates / Phosphates = Uremic acids
5. Exogenous

Question 4

ID specific acid-base disturbance most commonly associated w/ INCREASED anion gap

Answer 4

Endogenous Anions

1. Uremic acids = Renal azotemia
2. Lactic acid = Lactic acidosis
3. Ketoacids = Ketoacidosis (diabetes, pregnancy)

Exogenous Anions

4. Ethylene glycol toxicity (glycolic, glyoxylic, oxalic acids)
5. Salicylate/ Aspirin toxicity

Question 5

ID specific acid-base disturbance most commonly associated w/ DECREASED anion gap

Answer 5

1. Hypoalbuminemia

- Albumin = weak acid

Question 6

ID specific acid-base disturbance most commonly associated w/ NEGATIVE anion gap

Answer 6

Bromide toxicity
KBr = anticonvulsant drug
-Detecting Br- instead of Cl- (non-physiologic)

Question 7

Which is more clinically significant: increase / decreased anion gap?
What type of disturbance will be associated with it?

Answer 7

INCREASE anion gap

–associated w/ Titrational acidosis

Question 8

What is increased anion gap associated with on chem panel?

Answer 8

decreased TCO2

-due to consumption as a buffer