60% OF HUMAN BODY IS WATER! How to Determine The Volume of Body Fluids Compartments?? Oedema Dehydration

1. Body Fluids
“MohmmadRjab” S. Seder

2. ≈ 60% OF HUMAN BODY IS WATER!
AND WE HAVE MADE
FROM WATER
EVERY LIVING
THING
Quran 21:30

3. Total Body Water

4. • 40% is intracellular fluid (ICF)
i.e. fluid inside the cells.
• 20% is extracellular fluid (ECF) i.e. fluid outside the cells. Further divided into:
• Interstitial Fluid (ISF)- 15%
• Plasma- 5%
≈ 60% OF HUMAN BODY IS WATER!

5. ≈ 60% OF HUMAN BODY IS WATER!
• 40% is intracellular fluid (ICF)
i.e. fluid inside the cells.
• 20% is extracellular fluid (ECF) i.e. fluid outside the cells. Further divided into:
• Interstitial Fluid (ISF)- 15%
• Plasma- 5%

7. Distribution of Total Body Water
COMPARTMENTS VOLUME (L) PERCENTAGE %
BODY WEIGHT BODY WATER
TOTAL BODY WATER 42 60 100
ICF 28 40 67
ECF 14 20 33
PLASMA (25%) 3.5 5 8
INTERSTITIAL FLUID 10.5 15 25
TRANSCELLULAR FLUID
MESENCHYMAL TISSUE
(75%)

8. Percentage of Water in The Body
• Total Body Water varies depending on body fat:
 Infant: 73%
 Male adult: 60%
 Female adult: 40-50%
 Effects of obesity
 Old age 45%

9. Water content varies in different body organs and
tissues, from as little as 8 percent in the teeth to as
much as 85 percent in the brain.

11. ECF Vs ICF
ECF
• Most abundant cation: Na+
• Most abundant anion: Cl-
ICF
• Most abundant cation: K+
• Anions are protein and
phosphates (HPO4
-2)
• Also called internal environment
or milieu interior
ICF ECF
Volume 40% 20%
Major
ions
K+
Proteins
Na+
Cl-
pH 7.0 7.4

12. Movement of Body Fluids
• Body fluids are not static.
• Fluids and electrolytes shift from
compartment to compartment.
• Emphasis is always on maintaining
homeostasis.

13. Composition of Body Fluids
• Body fluids contain water and solids. Solids are organic and
inorganic substances.

14. Composition of the
ICF, IF, and plasma
The graph shows the composition of the ICF, IF,
and plasma. The compositions of plasma and IF
are similar to one another but are quite different
from the composition of the ICF

15. You're looking at Plasma, a typical body
fluid

16. Significance of Body Fluids
• In transport mechanism: body
water forms the transport medium
by which nutrients and other
essential substances enter the
cells and wastes come out of the
cells.

17. Significance of Body Fluids
• In Metabolic reactions: water
inside the cells forms the medium
for various metabolic reactions,
which are necessary for growth
and functional activities of the cells

18. Significance of Body Fluids
• In Texture of tissues: water inside the
cells is necessary for the characteristic
form and texture of various tissues.
• In Temperature regulation: body water
plays a vital role in the maintenance of
normal body temperature.

19. Regulatory Mechanisms
• Hypothalamus
Thirst mechanism
• Kidneys
Kidney Function
• Hormones
Renin
Angiotensin
Aldosterone
Anti-Diuretic Hormone

20. How to Determine The Volume of Body
Fluids Compartments??

21. Measurements of Body Fluids
INDICATOR DILUTION METHOD
fluid
sample
the
in
indicator
of
ion
concentrat
indicator
of
Amount
Fick's Principle Dilution Principle
1- A known amount of indicator is injected intravenously. The indicator should
be inert, non-toxic and not used by tissue.
2- Enough time is allowed for even distribution of indicator.
3- A sample is taken to determine concentration (dilution) of indicator volume.
Volume of distribution = V = M / C

22. C1 x V1 = C2 x V2

23. Prerequisite for Accurate Body Fluid
Measurements
• Non-toxic
• Mix-evenly
• Relatively easy to measure.
• No effect on distribution of
water.
• Must be unchanged &if changed
must be known.

24. Measurement of fluid volume

25. Measurement of Total Body Water
• By injecting marker which evenly
distribute in all compartment of body.
• Markers used
• Deuterium Oxide (D2O) / (2H2O)
• Tritium Oxide (3H2O)
• Aminopyrine
• Antipyrine

26. Measurement of ECF Volume
• Marker should not enter the cell but freely pass through capillary
membrane.
• Markers used:
• Radioactive substances _Na, Cl,Bromide sulphate, Thiosulphate
• Non-Metabolizable saccharides_ Inulin (Most accurate), Mannitol, Sucrose

27. Unfortunately, some bromine -82 also distributes into
the cells. Thus, bromine measurements of the ECF
volume frequently over-estimate the ECF volume

29. Measurement of Plasma Volume
• Marker should bind strongly
with plasma proteins and
should not diffuse into
Interstistium.
• Markers used:
• Radioactive iodine (I121)
• Evan’s blue dye
• Radioactive isotopes of
Chromium (Cr51)

30. Measurement of ICF Volume
• Cannot be measured directly.
• So, ICF = TBW - ECF

31. Measurement of Interstitial Fluid Volume
Interstitial Fluid Volume = ECF – Plasma volume

32. Estimating the blood volume on the basis
of the measured plasma volume
Hematocrit: is the volume percentage of red blood
cells in blood, measured as part of a blood test.

33. Water Balance
• Body fluid levels are maintained at normal levels when the intake
and output of water are balanced.
• When the intake is more than the output then a positive water
balance develops.

35. Physiological Positive Water Balance
• Growth
• Convalescence
• Pregnancy

36. Pathological Positive Water Balance
OEDEMA
0
• Oedema: Abnormal accumulation of
water in normally existing space in the
body.
• Oedema develops in
• Heart Failure
• Renal failure
• Malnutrition
• Inflammation of tissue

37. Oedema
Oedema is mostly extracellular and may develop due to:
 Increase in capillary hydrostatic pressure
 Decreased colloidal osmotic pressure
 Increased permeability of the capillary
 Lymphatic obstruction
 Failure of kidney to excrete excess water

38. Oedema
• Edema is the accumulation of excess water in the tissues.
• It is most common in the soft tissues of the extremities.
• The symptoms of edema include swelling of the subcutaneous
tissues, an increase in the normal size of the limb, and
stretched, tight skin.

39. Negative Water Balance
• Physiological Negative Water Balance: occurs during exercise,
working in hot sun.
• Pathological Negative Water Balance: Is seen in
dehydration, burns, hemorrhage, vomiting, diarrhea.
When the output is more than input, negative water balance
develops.

40. Dehydration
• Excessive loss of body water leading to a decline in body
water level is called dehydration.
• Dehydration may be due to:
• Simple water loss.
• Loss of bothwater and electrolytes.

41. Dehydration- Excessive loss of body water
is seen in:
• Excess body water loss as in diarrhea
• Severe vomiting
• Excessive sweating
• Fluid loss inburns
• Addison’s disease
• Diabetes mellitus and Diabetes insipedus
• Renal disease

42. The clinical symptoms associated with
severe dehydration are:
• Low cardiac output
• Rapid pulse rate
• Low blood pressure
• Decreased skin turgor
• Acidosis
• Sunken eye balls
• Lethargy, confusion and coma
• excessive sleepiness
• lessened urine output
• Intracellular dehydrationmay lead to death

43. Treatment of Dehydration
• The replenishment of body with
water and electrolytes.
• Electrolytes and pH should be
monitored carefully.

44. Exchangeable Ions
• All body K+ is exchangeable
• 65-70% of Na is Exchangeable.
• All Ca &Mg Non-exchangeable.
• Only exchangeable solutes –
Osmotically active