Kleinschmidt - acid base

Question 1

what do you have if you have a low pH and a normal pCO2

Answer 1

metabolic acidosis

Question 2

what do you have if you have a low pH and a high pCO2

Answer 2

respiratory acidosis

Question 3

elevated anion gap acidosis mnemonic

Answer 3

MUDPILES

Methanol

Uremia - creatinine >5, BUN > 60, gap rarely over 20

DKA

Propylene glycol (used to be paraldehyde, but not used anymore)

Iron or isoniazid

Lactic acid

Ethylene glycol (also ethanol) - see oxalate urine crystals

Salicylates

Question 4

what would cause a normal gap acidosis and mnemonic

Answer 4

either they are taking and acid (rare) or they are loosing bicarb

HARD-ASS

Hyperalimentation
Addison disease
Renal tubular acidosis
Diarrhea
Acetazolamide
Spironolactone
Saline infusion

Question 5

Causes of chloride unresponsive metabolic alkalosis

Answer 5

due to high aldosterone

Cushing’s
Bartter’s

Question 6

causes of respiratory acidosis

Answer 6

airway obstruction
COPD
sedation due to drugs
ALS, guillon barre

Question 7

if you have a chronic respiratory acidosis, how would you expect your bicarb change in relation to your pCO2

Answer 7

pCO2 goes up 10 points ->

bicarb compensates up 3 points

Question 8

acute vs chronic bicarb (kidney) compensation in respiratory alkylosis

Answer 8

acute:
pCO2 drops 10 ->
bicarb drops 2

chronic:
pCO2 drops 10 ->
bicarb drops 4

Question 9

causes of respiratory alkylosis

Answer 9

anything that can cause tachypnea

anxiety
coke
pregnancy

Question 10

how to calculate the osm gap

Answer 10

Measured - calculated

calculated:
2*Na + (glu/18) + (BUN/2.8)

it is normally around 10

Question 11

what does the oms gap mean

Answer 11

if you have an osm gap that is over ten, it means that you have more solute in the plasma than just sodium, glucose, and urea.

measured (actual total amount of solute) - calculated (just the main solutes)

Question 12

what is a delta gap and what is normal

Answer 12

drop in bicarb in relation to the anion gap

for every 1 increase in the anion gap, there is normally 1 drop in the bicarb for a basic metabolic acidosis.

if the bicarb doesn’t drop like you would expect, you have a high delta gap

(gap - 12) / (24 - bicarb)

Question 13

normal serum bicarb

Answer 13

24

Question 14

why does it matter if a COPD patient is a “retainer”

Answer 14

if they retain CO2 a lot, then their respiratory drive is probably based on hypoxic conditions. If you give them O2 in the hospital, you take away that drive and they can stop breathing.

if their bicarb is in the 30s, they are probably a retainer

Question 15

normal arterial pCO2

Answer 15

40

Question 16

acute vs chronic bicarb (kidney) compensation in respiratory acidosis

Answer 16

in acute,

pCO2 up 10 ->
HCO3 up 1

in chronic

pCO2 up 10 ->
HCO3 up 3