2. Basic physiology
Total body water- 60% of body weight
I.C.F 40% of E.C.F 20%
Body Water of Body Water
2/3 of
body
water
1/3 of Body
water
3. Distribution of body fluid
Intra
cellular
fluid-40%
Plasma 5%
Interstitial
fluid 15%
E.C.
F
1/3
I.C.F
2/3
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4. FLUID VOLUME- calculation
Fluid
type
Total ICF ECF Interstiti
al
Plasma
% of
body
weight
60% 40% 20% 15% 5%
Volume
for 70 kg
wt
42L 28L 14L 10.5L 3.5L
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6. Normal daily insensible fluid loss
=700ml
Insensible fluid input = 300ml due to oxidation
Insensible fluid loss = 500ml through skin
400 ml through lungs
100 ml through stool
Fluid loss- fluid input= 1000-
300ml=700ml
Daily fluid requirement= urine o/p+
700ml
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8. Major ions
ECF ICF
Cation Sodium Potasium &
magnesium
Anion Cloride &
bicorbonate
Phosphate ,
sulphate &
protein
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9. Units of measurement
Ion- atom/group of atoms
Anion- negative
Cation- positive
Mole – atomic/molecular wt of that substance
Milimole- 1/1000 mole
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10. Molecular wt
Substance Symbol Atomic/molecular wt
Calcium Ca2+ 40.1
Carbon C 12
Cloride ion Cl - 35.5
Hydrogen ion H+ 1
Magnesium ion Mg 2+ 24.3
Oxygen O 16
Phosphorus P 31
Potassium ion K+ 39.1
Sodium ion Na+ 23
Ammonium NH 4+ 18
Bicarbonate ion HCO3- 61
Phosphate ion PO43- 95
WATER H2O 18
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11. Equivalent & mili-equivalent
An equivalent is the atomic weight in grams x valence
e.g. Na+, Cl-
Ca++
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13. Relationship bet mEq & mg
mg/dl x 10 x valence
mEq/L = --------------------------
mol. Weight
If 1 gm salt NaCl is added to 1 lit water, wt will be the
conc. In mEq/L
NaCl 1gm/L =1000mg/L= 100mg/ dl, valence=1
mEq/L=100x10x1/ 58.5 (Na=23+Cl=35.5)
=17.1
1gm NaCl/L= 17.5 mEq/L
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14. Convert mEql/l to mg/dl
Eg. If 1 lit NaCl contains 154 mEq NaCl, how much
mg/dl NaCl
mEq/L x mol. Wt
mg/dl= --------------------------
10 x valence
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15. Osmotic pressure & osmolality
OP= distribution of water among different fluid
compartment, particularly bet ECF & ICF
Osmotic pressure generated by solution ~ no. of
particles/unit volume of solvent, not to type, valency
or weight
To generate OP the solute must be unable to cross cell
membrane
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16. Osmole= unit of measurement of OP, one osmol
= 1 gm molecular wt ( 1mol) of any nondissociable
substance and contains
6.024 x 10 23 particles
Miliosmol= 1/1000 osmol
Osmolarily= solvent is measured in Litre
Osmolality= solvent is measured in Kilogram
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17. Basic principles for IV Fluid
Therapy
Advantage
1. Accurate, controlled, predicted
2. Immediate response
3. Prompt correction of serious fluid & electrolyte
disturbances
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18. Indications
1. Oral intake not possible coma, anaesthesis.
2. Severe vomiting, diarrhoea
3. Moderate to severe dehydration & shock, where
urgent & rapid fluid replacement needed
4. Hypoglycemia
5. Vehicle
6. Total parenteral nutrition
7. Critical problems- shock, anaphylaxis, cardiac arrest,
severe asthma, forced diuresis in overdose,poisoning,
urinary stone
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19. Disadvantages
1. Most expensive
2. Strict asepsis needed
3. Possible only in hospitalized
4. Improper selection, volume, rate, technique leads
complications
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