COMPONENTS OF BODY FLUIDS
| A | 51 Cr | |
| B |
59 Fe |
|
| C |
32 P |
|
| D |
121 I |
Plasma is the fluid portion of the blood which aids in the transport of other substances in the body. Total plasma volume in relation with body weight is:
| A |
5% |
|
| B |
10% |
|
| C |
20% |
|
| D |
25% |
The following are true about body water:
| A |
Water constitutes 60% of the body weight |
|
| B |
Plasma volume constitutes 10% of the total body water |
|
| C |
ECF volume can be determined by dilution methods |
|
| D |
10% is intracellular water |
D20 (Deuterium oxide) is used to measure volume of
| A |
Blood |
|
| B |
Total body water |
|
| C |
Extracellular fluid |
|
| D |
Intracellular fluid |
Most accurate measurement of extracellular fluid volume (ECF) can be done by using :
| A |
Sucrose |
|
| B |
Mannitol |
|
| C |
Inulin |
|
| D |
Aminopyrine |
Which of the following methods is not used for measurement of body fluid volumes?
| A |
Antipyrine for total body water |
|
| B |
Insulin for extracellular fluid |
|
| C |
Evans blue for plasma volume |
|
| D |
I125-albumin for blood volume |
The apparent volume of distribution of a drug less than 5 liters implies that the drug is predominantly in which of the following compartment?
| A |
Extracellular fluid |
|
| B |
Total body water |
|
| C |
Intracellular fluid |
|
| D |
Intravascular fluid |
When ICF and ECF of child becomes equal to adult person –
| A |
1 year |
|
| B |
2 year |
|
| C |
3 year |
|
| D |
4 year |
Which of the following methods is NOT used for measurement of body fluid volumes ?
| A |
Antipyrine for total body water |
|
| B |
Inulin for extracellular fluid |
|
| C |
Evans blue for plasma volume |
|
| D |
125I-albumin for blood volume |
Which of the following is true:
September 2010
| A |
ExtraCellular Fluid is rich in organic anion |
|
| B |
ECF is more than Intra Cellular Fluid |
|
| C |
High sodium to potassium ratio is seen in ECF |
|
| D |
ECF is potassium ion rich |
Total body water is ‑
| A |
40% of body weight |
|
| B |
20% of body weight |
|
| C |
10% of body weight |
|
| D |
60% of body weight |
False about total body water (TBW) ‑
| A |
ICF is 2/3rd of TBW |
|
| B |
In newborn TBW is 60% of body weight |
|
| C |
Premature newborns have more TBW |
|
| D |
In adults, TBW is 60% of body weight |
Which of the following statements is true about body fluid osmolarity?
| A |
Major contributor is proteins |
|
| B |
Major contributor is Na+ |
|
| C |
ECF osmolarity is 250 mOsm/L |
|
| D |
Measured by dilution method |
Total body water is ‑
| A |
14 litres |
|
| B |
28 litres |
|
| C |
35 litres |
|
| D |
42 litres |
Plasma volume is measured by ‑
| A |
Inulin |
|
| B |
Evans blue |
|
| C |
Mannitol |
|
| D |
D2O |
Red cell volume can be measured by injecting tagged red blood cells. All of the following are used to tag red cell, EXCEPT:
| A |
51 Cr |
|
| B |
59 Fe |
|
| C |
32 P |
|
| D |
121 I |
Red cell volume is the volume occupied by all the circulating red cells in the body. It can be measured by sustracting the plasma volume from total body water. It can also be measured by injecting tagged red blood cells and measuring the fraction of red cells that is tagged.51 Cr radio isotope of chromium is commonly used. Isotopes of iron(59Fe) and phosphate (32P)and antigenic tagging is also used.
Ref: Ganong’s Reveiw of Medical Physiology, 21st Editon, Page 3
Plasma is the fluid portion of the blood which aids in the transport of other substances in the body. Total plasma volume in relation with body weight is:
| A |
5% |
|
| B |
10% |
|
| C |
20% |
|
| D |
25% |
Normal plasma volume is about 5% of body weight, or roughly 3500 mL in a 70-kg man.
- Plasma clots on standing, remaining fluid only if an anticoagulant is added.
- The plasma proteins consist of albumin, globulin, and fibrinogen fractions.
- These proteins therefore exert an osmotic force of about 25 mm Hg across the capillary wall that pulls water into the blood.
- The plasma proteins are also responsible for 15% of the buffering capacity of the blood.
The following are true about body water:
| A | Water constitutes 60% of the body weight | |
| B |
Plasma volume constitutes 10% of the total body water |
|
| C |
ECF volume can be determined by dilution methods |
|
| D |
10% is intracellular water |
A i.e. Water constitutes 60% of body weight
D20 (Deuterium oxide) is used to measure volume of
| A |
Blood |
|
| B |
Total body water |
|
| C |
Extracellular fluid |
|
| D |
Intracellular fluid |
B i.e. Total body water
Most accurate measurement of extracellular fluid volume (ECF) can be done by using :
| A |
Sucrose |
|
| B |
Mannitol |
|
| C |
Inulin |
|
| D |
Aminopyrine |
C i.e. Inulin
| ECF |
|
Which of the following methods is not used for measurement of body fluid volumes?
| A |
Antipyrine for total body water |
|
| B |
Insulin for extracellular fluid |
|
| C |
Evans blue for plasma volume |
|
| D |
I125-albumin for blood volume |
D i.e. I125 -albumin for blood volume
|
Body Fluid |
Method of Measurement |
|
Total body fluid Mn : “DAT” |
– Deuterium (2H20, D20 most commonly used)Q – AminopyrineQ, Antipyrine – Tritium oxide. (3H20) |
|
Extracellular fluid volume |
– SucroseQ, Tiosulfate |
|
Mn : “SIMaN” |
– InulinQ (most accurate measurement), 1125 iothalamate |
|
|
– MannitolQ, Na22 |
|
Plasma volume |
– Evan’s blueQ (T-1824) |
|
Mn : [P E A] |
– Albumin labeled with radioactive iodineQ (1125) |
|
Intracellular volume |
Total body fluid – Extracellular fluid |
|
(Cannot measured directly) |
|
|
Interstitial fluid volume (Cannot measured directly) |
ECF – Plasma volume |
|
Blood volume |
– Crsi labelled RBC or = Plasma volume |
|
|
1 – Hematocrit |
| A | Extracellular fluid | |
| B |
Total body water |
|
| C |
Intracellular fluid |
|
| D |
Intravascular fluid |
Ans is ‘C’ i.e., Intracellular fluid
A drug with a high volume of distribution has more concentration in tissue and less in plasma.
A drug with a low volume of distribution has concentration only in plasma (intravascular)
Relationship between the volume of distribution and extent of distribution
|
Vd (L) |
% body weight |
Extent of distribution |
|
< 5 |
7 |
only in plasma |
|
5-20 |
7-28 |
In extracellular fluid |
|
20-40 |
28-56 |
In total body water |
|
>40 |
>56 |
In deep tissues; bound to peripheral tissues |
| A | 1 year | |
| B |
2 year |
|
| C |
3 year |
|
| D |
4 year |
Ans. is ‘a’ i.e., 1 year
o In fetus, ECF is much larger than ICF.
o By the age of 1 year, ratio of ICF to the ECF volume approaches adult level.
| A |
Antipyrine for total body water |
|
| B |
Inulin for extracellular fluid |
|
| C |
Evans blue for plasma volume |
|
| D |
125I-albumin for blood volume |
Ans. D i.e. 125I-albumin for blood volume
- Blood cell volume is determined by the hematocrit value and radioisotope method (mainly Cr52).
MEASUREMENT OF BODY FLUID COMPARTMENTS
- Measurement of body fluid volumes is done by ‘Dilution method’
| VOLUME | MEASUREMENT |
| TBW |
|
| ECF |
|
| PLASMA VOLUME(PV) |
|
| RED CELL VOLUME |
|
| ICF |
|
September 2010
| A |
ExtraCellular Fluid is rich in organic anion |
|
| B |
ECF is more than Intra Cellular Fluid |
|
| C |
High sodium to potassium ratio is seen in ECF |
|
| D |
ECF is potassium ion rich |
Ans. C: High sodium to potassium ratio is seen in ECF
Remember:
- ICF is more abundant than ECF
- ECF contains large amounts of sodium and chloride ions
- ICF contains large amount of potassium ions and phosphate ions
| A |
40% of body weight |
|
| B |
20% of body weight |
|
| C |
10% of body weight |
|
| D |
60% of body weight |
Ans. is d i.e., 60% of body weight
False about total body water (TBW) ‑
| A |
ICF is 2/3rd of TBW |
|
| B |
In newborn TBW is 60% of body weight |
|
| C |
Premature newborns have more TBW |
|
| D |
In adults, TBW is 60% of body weight |
Ans. ‘B’. In newborn TBW is 60% of body weight
- In a term newborn, TBW is 70-80% of body weight.
- It is more in premature newborn than in term newborn.
| A |
Major contributor is proteins |
|
| B |
Major contributor is Na+ |
|
| C |
ECF osmolarity is 250 mOsm/L |
|
| D |
Measured by dilution method |
Ans. is ‘B’ i.e., Major contributor is Na+
- The osmolarity is the number of osmoles per liter of solution (eg. Plasma).
- Osmolarity is affected by the volume of the various solutes in the solution and the temperature.
- About 80% of the total osmolarity of the interstitial fluid and plasma is due to sodium and chloride ions, whereas for intracellular fluid almost half the osmolarity is due to potassium ions and the remainder is divided among many other intracellular substances.
Total body water is ‑
| A |
14 litres |
|
| B |
28 litres |
|
| C |
35 litres |
|
| D |
42 litres |
Ans. is ‘d’ i.e., 42 litres
Plasma volume is measured by ‑
| A |
Inulin |
|
| B |
Evans blue |
|
| C |
Mannitol |
|
| D |
D2O |
Ans. is ‘b’ i.e., Evans blue