equatios

Question 1

normal AG

Answer 1

8-12

Question 2

stool osmotic gap

Answer 2

290-2(stool Na+stool K)

Question 3

how to interpret stool osmotic gap

Answer 3

under 50 is secretory, over 100 is osmotic

Question 4

causes of secretory diarrhea

Answer 4

bacterial toxins, VIPoma, gastrónoma, thyroid medullary cancer

Question 5

causes of osmotic diarrhea

Answer 5

celia, whipple, pancreatic insufficiency, laxative abuse, lactose intolerance aka malabosprtion

Question 6

SAAG calculate

Answer 6

serum albumin- ascites albuin

Question 7

interpreting SAAG

Answer 7

<1.1 is NOT related to portal HTN, >1.1 is portal HTN

Question 8

4 causes of SAAG <1.1

Answer 8

nephrotic TB malignancy, peritoneal carcinomatosis

Question 9

causes of SAAG >1.1

Answer 9

pre sinusoidal (splenic v or portal v thrombosis, schistosomiasis) sinusoidal (cirrhosis ) and post sinusoid (R heart failure budd chair, constrictive pericarditis)

Question 10

serum osm formula

Answer 10

(2*serum Na) + (BUN/2.8)+ (glucose/18)

Question 11

osmolol gap

Answer 11

measured- calculated

Question 12

normal osmolol gap

Answer 12

under 10

Question 13

what could cause a high osmolol gap

Answer 13

mannitol, ethylene glycol, sorbitol, PEG< methanol

Question 14

how to calculate water deficicit

Answer 14

total body water * ((serum Na/140)-1)

Question 15

what is total body water

Answer 15

60% of total body weight

Question 16

corrected calcium formula

Answer 16

measured calcium + (0.8)(4-albumin)

Question 17

corrected Na formula

Answer 17

measured Na+ 0.016 (Glucose-100)

Question 18

winters

Answer 18

expected PCo2 = 1.5 (HCO3)+ 8 +/- 2

Question 19

Aa gradient

Answer 19

PAo2-Pao2= Pio2- (PaCO2/0.8)-PaO2

Question 20

how to calculate PiO2

Answer 20

(Patm-47)* FiO2

Question 21

what is PiO2 on RA at sea level

Answer 21

150

Question 22

minute ventilation

Answer 22

tidal volume * RR

Question 23

3 causes of elevated AA gradient

Answer 23

VQ mismatch, diffusion limited, R to L shunt

Question 24

FENa formula

Answer 24

100* (ScrUna)/(SnaUcr)

Question 25

how to interpret FENa

Answer 25

< 1%= pre renal, >1% is intrinsic renal

Question 26

delta delta formula

Answer 26

change in AG/ change in HCO3

Question 27

when to use Delta delta

Answer 27

in high anion gap metabolic acidosis

Question 28

delta delta should = what if complicated by an alkalosis

Answer 28

over 2

Question 29

delta delta <0.4 means

Answer 29

high Cl normal anion gap metabolic acidosis

Question 30

normal high anion gap metabolic acidosis (pure) means delta delta of what

Answer 30

1-2