Laboratory Values

Question 1

Serum Sodium

Answer 1

A major cation of ECF. Maintains osmotic pressure and assists in the transmission of nerve impulses. Absorbed in the small intestine.

Question 2

Serum Potassium

Answer 2

Major cation of ICF. Regulates cellular water balance, electrical conduction in muscle cells and acid base balance. Balance maintained by the kidneys.

**patient with a high white cell count may have false high potassium levels

Question 3

aPTT- Activated Partial Thromboplastin Time

Answer 3

20-36 seconds

Measures how well the clotting system is functioning. Measures time in seconds for plasma to clot after partial thromboplastin is added to it.

aPTT - is 1.5 x 2.5 times the normal value when patient is on heparin therapy.

Question 4

PT - Prothrombin Time

Answer 4

9. 6-11.8 seconds (adult male)
10. 5-11.3 seconds (adult female)

Measures the time in seconds of clot formation.

Used to monitor warfarin therapy or diagnose coagulation disorders.

Question 5

INR - International Normalized Ratio

Answer 5

2-3 - standard warfarin therapy
3-4.5 - high does warfarin therapy

Used to measure the effectiveness of oral anticoagulants.

Question 6

Platelets

Answer 6

150,000 - 400,000 cells per minute

Produced by the bone marrow, function in hemostatic plug formation, clot retraction and coagulation factor activation.

Question 7

ESR - Erythrosedimentation rate

Answer 7

0-30mm/hr

Rate at which erythrocytes settle out of anti-coagulated blood in 1 hour.

Question 8

Hematocrit

Answer 8

35-52%

The proportion of blood that contains red blood cells. Used to diagnose anemia or polycythemia.

Question 9

CK - Creatinine Kinase

Answer 9

26-174 units/L

Enzyme found in muscle and brain tissue. Reflects damage due to cell trauma.

Levels rise within 6 hours of damage and peak at 18 hours.

Question 10

Troponin

Answer 10

Troponin i: 0.6-1.5 ng/mL
Troponin t: 0.1-0.2 ng/mL

Protein released by the myocardium into the bloodstream after an infarct.

Question 11

Myoglobin

Question 12

ANP - Atrial Natriuretic Peptides

Answer 12

22-27 pg/ml

Used in cardiac atrial muscle. Indicates heart failure.

Question 13

BNP - Brain Natriuretic Peptides

Answer 13

less than 100

Question 14

Albumin

Answer 14

3.4-5 g/dL

Plasma protein of the blood which transports bilirubin, fatty acids, medications, and hormones which are insoluble in water.

Levels of this protein increase in conditions like:

• dehydration
• metastatic carcinoma
• diarrhea
• acute infection
• ascites
• alcoholism

Question 15

Ammonia

Answer 15

10-80 mcg/dL

Byproduct of catabolism which is metabolized by the liver into urea. Levels elevate resulting from hepatic dysfunction and can lead to encephalopathy.

Question 16

ALT - Alaning aminotransferase

Answer 16

10-40 units / L

Used to identify inflammation and damage to the liver

Question 17

AST - Aspartate aminotransferase

Answer 17

10-30 units/L

Used to identify patients with liver cell inflammation, damage or disease.

Question 18

Amylase

Answer 18

25-151 units/L

Enzyme produced by the pancreas and salivary gland which aids in the digestion of complex carbohydrates and is excreted by the kidneys.

Helps detect chronic and acute pancreatitis.

Question 19

Lipase

Answer 19

10-140 units/L

Pancreatic enzyme which converts fats and triglycerides into fatty acids and glycerol.

Helps diagnose pancreatic disorders.

Question 20

Bilirubin

Answer 20

Direct - 0-0.3 (intestines)

Indirect -

Question 21

HDL value

Answer 21

60 mg/dL and higher

Question 22

Total Lipid value

Question 23

LDL value

Question 24

Triglycerides

Question 25

Protein

Answer 25

6-8 g/dL

Regulates osmotic pressure and is required for the formation of many hormones, enzymes and antibodies. Also the building material for skin, hair, eyes, nails and internal organs.

Question 26

Fasting Glucose Test

Answer 26

Patient fasts for 8-12 hours prior to test (or if diabetic withhold morning medication). Fasting level should be 70-100 mg/dL.

Test used to check for diabetes mellitus.

Question 27

Normal Glucose Level

Answer 27

60-110 mg/dL

Question 28

Fasting Glucose Level

Answer 28

70-100 mg/dL

Question 29

Glucose tolerance test

Answer 29

Administration of IV or oral glucose followed by checking of levels. If glucose levels peak at higher than normal levels 1-2 hours after administration and levels are slower than normal to return to fasting levels then diagnosis of diabetes is confirmed.

Baseline fasting 60-100 mg/dL
60 minutes fasting

Question 30

Glycosylated hemoglobin - HbA1c

Answer 30

Reflects how good control of glucose has been over 3-4 month period.

Good control: 7%
Fair control: 7-8%
Poor control: > 8%

Question 31

Serum creatinine

Answer 31

0.6-1.3 mg/dL

Specific indicator of renal function. Increased levels indicate a slowing of the eGFR.

Question 32

Blood Urea Nitrogen

Answer 32

8-25 mg/dL

Formed in the liver by enzymatic breakdown. High levels indicate a slowing eGFR level.

Question 33

Calcium

Answer 33

8.6-10 mg/dL

Aids in blood clotting by converting prothrombin to thrombin. Aids in bone formation, nerve impulse transmission and muscle contraction.

Question 34

Magnesium

Answer 34

1.6-2.6 mg/dL

Used in blood clotting, regulates neuromuscular activity, modifies enzyme activity and effects the metabolism of calcium. Used as an indicator to determine metabolic activity and renal function.

Question 35

Phosphorus

Answer 35

2.7-4.5 mg/dL

Absorbed from food. Important in bone formation, energy storage and release, urinary acid-base buffering and carbohydrate metabolism.

Question 36

Thyroid stimulating hormone level

Answer 36

0.2 - 5.4 mu/mL

Question 37

Thyroxine (T4)

Answer 37

5-12 mcg/dL

Question 38

Thyroxine free (FT4)

Answer 38

0.8-2.4 ng/dL

Question 39

Triiodothyronine (T3)

Answer 39

80-230 ng/dL

Question 40

White Blood Cell Count

Answer 40

4,500-11,000 cells/mm3

Immune defense system of the body.