3.4.1 Osmolality and Osmolal Gap

Question 1

Osmolality is measured clinically using an Osmometer

T or F

Answer 1

T

Question 2

Osmolality is based on the measurement of a decrease in

a. Melting point
b. Freezing point
c. Vapor pressure
d. Condensation

Answer 2

b and c

Question 3

When calculating osmolality, these are based on 3 osmotic particles,
namely:

S______(mmol/L),
G______ (mg/dl),
B_____(mg/dl).

Answer 3

Sodium
Glucose
BUN

Question 4

Calculated Osmolality:

2Na(mmol/L) + (Glucose mg/dL / 18) + (BUN mg/dL / 2.8)

T or F

Answer 4

T

Question 5

Effective screening method in Detecting the presence toxic compounds

a. Osmometry
b. Osmolal gap
c. Clark method

Answer 5

b

Question 6

The difference of measured osmolality determined by an osmometer

a. Osmometry
b. Osmolal gap
c. Clark method

Answer 6

b

Question 7

Osmolal gap = Measured osmolality - _________ osmolality

Answer 7

Calculated

Question 8

Reference value :

Serum osmolality:

a. 275-297 mOsm/kg
b. 250-300 mOsm/kg
c. 5-10 mOsm/kg
d. 3-7 mOsm/kg

Answer 8

a

Question 9

Reference value :

Osmolal gap

a. 275-297 mOsm/kg
b. 250-300 mOsm/kg
c. 5-10 mOsm/kg
d. 3-7 mOsm/kg

Answer 9

c

Question 10

Clinical significance:

OG > ____ mOsm/kg

a. 10
b. 12
c. 11

Answer 10

b

Question 11

OG > 12 mOsm/kg
Abnormal osmotic particles are present in plasma causes:

• Renal failure
• Diabetic insipidus
• Lactic acidosis
• Intoxication with alcohols

Which of the following does not belong?

Answer 11

Diabetic insipidus

Should be ketoacidosis

Question 12

Common application: ethanol intoxication

a. These toxic compounds increase osmolal gaps
b. These toxic compounds Decrease osmolal gaps

Answer 12

a