Chapter 4: Lab Values & Drug Monitoring

Question 1

Answer 1

Na
(135-145 mEq/L)

Question 2

Answer 2

Cl
(95-106 mEq/L)

Question 3

Answer 3

BUN
(7-20 mg/dL)
Elevated in renal impairment and dehydration

Question 4

Answer 4

Glucose
(70-110 mg/dL)

Question 5

Answer 5

SCr
(0.6-1.3 mg/dL)
May increase due to nephrotoxic drugs
False elevation due to
* SMX/TMP
* H2RAs
* Cobicistat

Question 6

Answer 6

HCO3
Venous: 24-30 mEq/L
Arterial: 22-26 mEq/L
increased by steroids & loop diuretics
decreased by topiramate

Question 7

Answer 7

K
(3.5-5 mEq/L)
Increased by: ACEs, ARBs, spironolactone, aliskiren, tacrolimus, canagliflozin, cyclosporine, SMX/TMP, drospirenone

Decreased by: albuterol, diuretics, insulin, sodium polystyrene sulfonate

Question 8

Answer 8

WBC
(4,000-11,000 cells/mm^3)

Question 9

Answer 9

Hgb
Males: 4.5-5.5 x 10^6 cells/uL
Females: 12-16 x 10^6 cells/uL

Question 10

Answer 10

Platelets
150,000-450,000 cells/mm^3
decreased by: heparin, LMWH, fondaparinux, linezolid, valproic acid

Question 11

Answer 11

Hct
Males: 38-50%
Females: 36-46%

Question 12

Therapeutic range:

Carbamazepine

Answer 12

4-12 mcg/mL

Question 13

Therapeutic range:

Digoxin

Answer 13

0.8-2 ng/mL (AF)
0.5-0.9 ng/mL (HF)

Question 14

Therapeutic range:

Gentamicin

Answer 14

Peak: 5-10 mcg/mL
Trough: < 2 mcg/mL

Question 15

Therapeutic range:

Lithium

Answer 15

0.6-1.2 mEq/L
trough only monitoring

Question 16

Therapeutic range:

Phenytoin/Fosphenytoin

Answer 16

10-20 mcg/mL

Question 17

Therapeutic range:

Free Phenytoin

Answer 17

1-2.5 mcg/mL

Question 18

Therapeutic range:

Procainamide

Answer 18

4-10 mcg/mL

Question 19

Therapeutic range:

NAPA (procainamide active metabolite)

Answer 19

15-25 mcg/mL

Question 20

Therapeutic range:

Combined Procainamide & NAPA

Answer 20

10-30 mcg/mL

Question 21

Therapeutic range:

Theophylline

Answer 21

5-15 mcg/mL

Question 22

Therapeutic range:

Tobramycin

Answer 22

Peak: 5-10 mcg/mL
Trough: < 2 mcg/mL

Question 23

Therapeutic range:

Valproic acid

Answer 23

50-100 mcg/mL

Question 24

Therapeutic range:

Vancomycin

Answer 24

Trough: 15-20 mcg/mL (serious infections: meningitis, bacteremia, osteomyelitis)

Trough: 10-15 mcg/mL (all other infections)

Question 25

Therapeutic range:

Warfarin

Answer 25

INR: 2-3
2.5-3.5 for mechanical mitral valve