Lab Work

Question 1

Ferritin elevated?

Answer 1

Acute phase reactant, compare to Hbg is it appropriate?

Question 2

RBC macrocytosis

Answer 2

B12/ Folate deficiency - consider chronic alcohol use

Question 3

Neutrophils up but WBC normal?

Answer 3

Consider immunosuppression, elderly

Question 4

INR?

Answer 4

If they are on Warfarin titrate accordingly, if elevated and not on Wafarin be very concerned - 1.5 is enough to bleed out

Question 5

RF elevated?

Answer 5

Think connective tissue disorder

Question 6

ANA elevated?

Answer 6

Think lupus - true lupus is an elevated RF and ANA

Anything over 1:160 is lupus, 1:80 is connective tissue and 1:320 is very very sick

Question 7

Lactate vs LDH

Answer 7

LDH - measure of myocardial damage and hemolysis

Lactate - acidosis from metabolism

Question 8

ANCA/ p-ANCA?

Answer 8

Tests for vasculitis

Question 9

Anti ds-DNA?

Answer 9

Final test for lupus (antibodies to your own DNA)

Question 10

Lots of IG?

Answer 10

Consider multiple myeloma

Question 11

CK?

Answer 11

Muscle breakdown

Question 12

Sky high testosterone/ estrogen/ DHEA?

Answer 12

Probably using the steroids

Question 13

Hepatitis B surface Ag

Answer 13

Rules out active infection

Question 14

Urine samples are best when?

Answer 14

First morning is better, no heavy work before, must test in 1 hour, 2-8C for 24 hours for CHEMICAL testing only

Question 15

Low specific gravity urine?

Answer 15

Basically H20 - diabetes insipidus

High specific gravity for urine - diabetes Mellitus

Question 16

Speckling on urine dip?

Answer 16

Solid RBC casts

Question 17

Urine nitrites?

Answer 17

Are a highly specific test, but not very sensitive for UTI

Question 18

Urine ketones sensitivity?

Answer 18

More sensitive than plasma ketones

Question 19

Urine protein?

Answer 19

Measures albumin - need to do 24 hour screen to figure out.

Question 20

Signs/ Sx of Tylenol OD

Answer 20

Right away no sx, N/V malaise
2-3 days, RUQ pain, change in blood chemistry - this is when the liver starts to die

After that the question is if the liver will recover or you will have liver failure

Question 21

When does the Rumack- Matthew nonogram

Answer 21

4-24 hours for the nonogram - draw the serum Tylenol - then if risk of toxicity - give NAC (usually given IV for 24 hours) and call poison control.

Question 22

Classic ASA overdose?

Answer 22

Tinnitus, signs of metabolic acidosis

Question 23

Osmolar gap?

Answer 23

Looking for large molecules in the blood - toxic alcohols, mannitol, etc

Question 24

How to calculate the osmolar gap

Answer 24

Measured - 2x Na + sticky (glucose) + BUN

Question 25

Hypokalemic? What’s the first step?

Answer 25

Is their BP high? Or not?

If yes then it is aldosterone

If no then it is either due to high pH, high insulin or catacholemines

Or poor intake

Question 26

Hyponatremia what do you have to check?

Answer 26

Is the glucose or TG also high? If yes then fake.

Is the serum osmolal off? If normal or high it is likely one of the two above. It needs to be low. This is in comparison to urine osmolo

Then look at the patient. Are they dry? Are they wet?
This gives volume status.

Then look at urine sodium is it high or low this will give cause.

Question 27

Urine sodium is not useful when?

Answer 27

Diuretics, on fluids take it before

Question 28

Approach to Hyponatremia

Answer 28

1. Is it true? High TGs or Glucose
2. Serum osmol - is it high, low or normal (this determines tonicity- if hypotonic get ->
3. Urine osmol - high? (ADH is active), low (aldosterone is active)
4. Volume status -compare urine sodium and urine osmol hypo (low sodium in urine, and high osmol (>100)) , euvolemic, hyper (low sodium in urine, high osmol), euvol- urine sodium normal, and high osmol

Remember that the urine osmol is relative to serum.

Causes of hypervol - heart failure, cirrhosis, nephrosis (you are just 3rd spacing) -
Causes hypovolemic - dehydration - give fluids, Lasix and fluid restrict.
Causes of euvolemic - SIADH, primary polydipsia, SSRI overdose, thyroid, adrenal insufficiency (AM cortisol and ACTH) - Fluid restriction

Question 29

Tx of severe hyponatremia

Answer 29

100cc 3% NS (increase sodium by 4-5 points), repeat up to 3 times. But in real life we don’t tend to do this
- Only use of patient has a sodium less than 120 and is showing severe features, seizures.

(Ideal sodium/ actual sodium)xTBW = amount of fluids in L
Then divide by 24 hours

Be cautious - undercorrect rather than overcorrect.

Question 30

Urine sodium when?

Answer 30

BEFORE tx hyponatremia

Question 31

BUN is up rest of kidney is normal

Answer 31

Digesting blood. Consider GI bleed