Electrolyte replenishers

1. ELECTROLYTE REPLENISHERS

3. BODY FLUID:
Contains various inorganic and organic ions, water, proteins, carbohydrates,
amino-acids (essential, non-essential) etc.
3- main compartment of body
 Intracellular (40-45%of body weight)
 Interstitial fluid (12-15%of body weight)
 Plasma/vascular fluid (3-5%of body weight)
In ordered to maintain the homeostasis ,each compartment are ionically
balanced.
Important function serves by electrolyte are:
To control osmosis of water between body compartment
To maintain acid-base balance needed for normal cellular activities.
To generate action potential and graded potential
Control secretion of hormones and neurotransmitters
Anionic electrolytes:
HCO3, Cl- , SO4 , HPO4
Cationic electrolytes:
Na+ K+, Ca+2, Mg+2 .

4. Ions Extracellular
concentration
Intra cellular
concentration
Plasma
concentration
mEq/L mEq/L mEq/L
Cations
Na+
K+
Ca++
Mg++
142
4
3
2
10
160
--
35
142
4
5
3
Anions
Cl-
SO4
--
HCO3
-
PO4
-
115
1
30
2
2
0
8
140
103
1
27
2
Organic Acids
5 -- 5
Proteins 1 55 16
Various concentration of important Electrolyte

5. . Role of major physiological cations and anions:
Important function serves by electrolyte are:
To control osmosis of water between body compartment
To maintain acid-base balance needed for normal cellular activities.
To generate action potential and graded potential
Control secretion of hormones and neurotransmitters.
Sodium ion (Na+)
Source: Marine foods like fish, water etc
Role:
Most important extracellular ion.
Plasma concentration 136-142 mEq/L.
Normal intake varies from 5-20gm per day
excess quantities get excreted through urine.
The Na+ level in the blood is controlled by
Aldosterone and antidiuretic (ADH) hormones
Normally in kidney, it plays important role in
excretion of sodium which is reabsorbs from
Glomerular filtration.
With chloride and bicarbonates it play
important role in acid base equilibrium.
Maintains osmotic pressure and excessive
fluid loss.
Plays important role in transmission of nerve
impulse.

6. Deficiency:
Hyponatremia:
Cause due to low serum sodium level/ concentration.
Excessive urination in case of diabetes insipidus results in loss of sodium ion concentration.
Excessive excretion in “metabolic acidosis”, diarrhoea and vomiting.
In “Addison’s disease” in which there occur a decreased excretion of hormones Aldosterone which is
anti-diuretic.
 Hypernatremia
Cause due to high serum sodium concentration.
Severe dehydration
Hyper Adrelanism (cushing syndrome)
Brain damage.
Excessive treatment with sodium salt.

7. Potassium ion (K+)
Source: Milk, vegetables, meat and whole
grains.
Role:
Most important intracellular electrolyte.
Plasma concentration 3.8-5 mEq/L.
Normal intake varies from 5-7gm per day.
Daily requirement is 1.5-4.5 gm.
Mainly important in contraction of muscle
(Cardiac muscle).
Transmission of nerve impulses.
Many biochemical activities are maintained
inside the cell.
It rapidly get absorbed from diet from GIT
and is rapidly get excreted through kidney.
That result in changes in acid-base balance
and activity of adrenal cortex.
Hyperkalemia:
Increase serum potassium level. ( renal failure,
dehydration, shock.)
In “Addison disease”- increases the serum K+ level.
Causes Cardiac and CNS depression, bradycardia,
poor heart sound, peripheral vascular collapse and
cardiac arrest.
Increase level of K+ brings about metal confusion,
weakness of respiratory muscles.
Hypokalemia:
Result due to low serum K+
Post-operative treatment which includes I.V.
administration of solution not having K+ for prolong
period.
Associated with malnutrition, gastrointestinal
losses, as in diarrhoea and in metabolic alkalosis.
In certain diuretics like acetazolamide,
chlorothiazide the K+ excretion increase.

8. Calcium ion (Ca++)
Source: Milk, cheese, green vegetables, eggs and fish.
Role:
Most important extracellular ion. The total plasma Ca++ has been 2.2-2.6 mEq/L.
Daily requirement in body is 0.8gm. minimum req. is 0.4g.
Ca++ associated with Vit.D and phosphorous in hardening of bones.
Also involve in coagulation of blood and in impulse propagation and in muscle contraction.
Important in release of AcH from preganglionic nerve terminal.
Greater amount needed during pregnancy and lactation. For child growt.
Deficiency:
Level of Ca++ is maintained by parathyroid hormone and calcitonin.
Under the condition like Vit. D. deficiency, renal failure and intestinal mal-absorbtion. Ca++
Absorption gets reduced.
If the ionized concentration becomes low, tetanic spasms or convulsion may take place.
If the ionized Ca++ is high, cardiac function are disturbed.

9. Phosphate ion (PO4¯):
Source: milk, milk product, whole grain legumes, nuts.
Role:
•Ions like H2PO4¯, HPO¯4 are main anion of intracellular fluids.
•Normal plasma concentration is 1.7-2.6mEq/L
•Total body phosphate is present in teeth and bones along with calcium. Mostly found in
phospholipids, ATP, DNA-RNA
•Play important role in buffer systems. Mainly occur as monohydrogenphosphate and
dihydrogenphosphate.
•Mainly involve in phosphorylation that involve the conversion of organic compound to phosphate
ester.
•Deficiency:
Phosphate deficiency associated with patient with calcium deficiency.
Phosphate depletion occurs as a result of renal tubular disordered or in patients consuming large
amount of antacid, specifically aluminum hydroxide

10. Electrolyte use for replacement therapy:
Replacement Therapy: Objective
To restore the volume and composition of body fluid.
Volume contraction is life threatening condition. In extreme case (Accident or during
surgery) 100ml per minute for 1000ml has been consider necessary.
A general rule is to replace one half of the estimated volume loss in the first 12-24 hours
of treatment.
During the disease condition like diarrhoea, vomiting, dysentery the fluid loss cause
disturbance of electrolyte balance

11. Potassium Replacement
Potassium Chloride: KCl (MW 74.56)
•I.P. Limit. Potassium chloride contains not less than 99 % calculated with reference to dried
substance. It occurs as sylvine (KCl) and Carnallite (KCl, MgCl2)6H2O contaminated with magnesium
sulphate and chlorides. It occurs as white crystalline solid, cubic crystals. It is less soluble in water than
sodium chloride, and slightly more soluble in boiling water, soluble in glycerin and insoluble in alcohol
•Preparation:
1. It is prepared by fusing Carnallite whereby liquefied magnesium chloride hexahydrate
is separated from the solid potassium chloride.
2. The crushed Carnallite is dissolved by boiling with liquor leaving other impurities
undissolved. These are filtered off and the filtrate is crystallizes to get cubic crystals of
potassium chloride.
3. It is also prepared in laboratory by reacting HCl with potassium carbonate or
bicarbonate
K2CO3 + 2HCl KCl + H2O +CO2
KHCO3 + HCl KCl + H2O +CO2

12. •Use:
•Electrolyte replenisher in potassium deficiency, familial periodic paralysis, Meniere’s syndrome
(disease of inner ear),
•antidote in digitalis intoxication, myasthenia gravis.
•Contraindication: renal impairment with oligouria, acute dehydration.
Potassium Chloride injection: Ringer injection
Calcium Replacement
Calcium Lactate: C6H10CaO6 xH2O (MW 308.30)
•I.P. Limit. Potassium chloride contains not less than 97% and not less than 103% of Calcium Chloride
dihydrate. It occurs as white odorless powder. The pentahydrate effloresces and becomes anhydrous at
120°. Aqueous solutions are prone to become moldy. It is soluble in water, practically insoluble in
alcohol.
•Preparation:
It is obtained by neutralizing a hot solution of lactic acid with calcium carbonate in slight excess. The
hot liquid is filtered and filtrate is evaporated to crystalline product

13. 2. It is also obtained by fermenting hydrolyzed starch with a suitable mold in the presence
of calcium carbonate
3. Or by fermentation of mother liquor resulting from the production of milk sugar and
chalk. The mixture is digested for a week at about 30°. The product is purified by
crystallization.
Use: An excellent source of calcium in oral treatment of calcium deficiency
•Physiological acid-Base balance
Objective:
Acid-base concentration maintenance.
Essential because the biochemical reaction taking place in living system is very sensitive
to small changes of acidity or alkalinity.
The normal concentration of free H+ in the extracellular fluid (ECF) is extremely small,
approximately 40 nmEq/L, which is equivalent to one millionth of a mEq/L concentration
of sodium.
Normal metabolism produces hydrogen in the form of volatile and fixed acids.
To maintain pH within its normal narrow range of 7.35 to 7.45, acids must be buffered or
excreted

14. Buffer system:
Main function of the buffer system is to prevent drastic changes in pH values in the blood.
Buffers are able to remove the excess H+ ion from body fluid and not from whole body
pH Regulation:
pH is controlled by two major and related processes
1) pH regulation. 2) pH compensation
Regulation is a function of the buffer systems of the body in combination with the
respiratory and renal systems,
Whereas compensation requires further intervention of the respiratory and/or renal
systems to restore normalcy.
Most important buffer systems in our body
are:
•Carbonic acid-bicarbonate buffer system.
•Phosphate buffer system.
•Haemoglobin buffer system.
Body fluids pH Ranges
Urine 4.5-8.0
Blood 7.4-7.5
Gastric juice 1.5-3.5
Saliva 5.4-7.5
Bile 6.0-8.5
Semen 7.2-7.6

15. Carbonic acid-bicarbonate buffer system:
Occurs in plasma and kidneys.
Bicarbonate ion act as weak base and accepts H+ to form carbonic acid.
As CO2 is produce in large quantity in metabolic reaction and from the environment they
are inhale, the amount of water in body are in plenty of amount hence the reaction between
these two give rise to carbonic acid in presence of enzyme carbonic anhydrase.
CO2 + H2O H2 CO3
•When H+ ion concentration is less then this carbonic acid get
dissociated into H+ ion and thus maintain the balance.
•Normal metabolism gives rise to more acid than bases. But
blood is made more acidic, therefore the body needs more
bicarbonate salt than it needs carbonic acid. Hence
physiological pH 7.4 the plasma is having about 24mEq/L of
bicarbonate in comparison to about 1.2mEq/L of carbonic
acid(ratio 20:1)

16. Phosphate buffer system:
•Occur in cell and kidney.
•The system consist of monohydrogenphosphate/dihydrogenphosphate anions.
•If there occurs an excess of H+ ion, the monohydrogen phosphate ion acts as the weak base by
accepting the proton.
HCl + Na2HPO4 NaCl + NaH2PO4
Strong acid weak base Salt + weak acid
•While the dihydrogen phosphate ion act as weak acid and is able to
neutralize the alkaline condition
NaOH + NaH2PO4 H2O + Na2HPO4
Strong base + weak acid Water + weak base
•Ex. In kidney if excess H+ ion in the kidney tubule combines with NaH2PO4.
•The sodium ion release in this reaction forms sodium bicarbonate by accepting
bicarbonate ion.
•The NaHCO3 then enter in the blood. The H+ ion that replaces Na+ becomes part of the
NaH2PO4. That goes into the urine.
•The ratio in intracellular fluid is about 4:1.1

17. Electrolyte used in acid-
base therapy:
Generally K+/Na+ compound such
as bicarbonate,lactate,acetate can be
used for treating metabolic acidosis.
Where as metabolic alkalosis can be
trated with ammonium salt,
important being ammonium
chloride.
Example. Sodium acetate, sodium
citrate, potassium bicarbonate,
sodium lactate. Ammonium
chloride. (Note:Monograph are
attch)

18. Electrolyte combination therapy:
When patient undergoes a surgery, he is unable to take normal diet therefore
combinations of glucose and saline solutions are usually sufficient in short term
therapy for restoring electrolyte loss. But in severe deficit of electrolytes due to
heavy blood loss or chronic diarrhea, solutions containing additional electrolytes
are usually required. The combination products are of two types :
1. Fluid maintenance therapy
2. Electrolyte replacement therapy
Electrolyte Concentration
mEq/L
Sodium 25-30
Potassium 15-20
Chloride 22
Bicarbonate 20-23
Phosphorous 3
Magnesium 3

19. The electrolyte concentrations in solutions for rapid initial
replacement are almost similar to the electrolyte
concentrations found in extracellular fluids. The electrolyte
concentrations of these solutions are given as.
Two types of solutions are used in replacement therapy:
i) Solution for rapid initial replacement
ii) A solution for subsequent replacement
Official compound used are:
Example.
1. Sodium chloride injection,
2. Compound sodium chloride
injection (Ringer injection),
3. Ringer solution lactated
(Hartmanns solution).

20. Oral rehydration salt/ therapy
Oral rehydration therapy is the use of modest amounts of sugar and salt added to
water in order to prevent and/or treat dehydration.
This dehydration is most commonly caused by diarrhoea and also caused by
vomiting
•Dehydration: Loss of water and dissolve salts from the body, occurring, for
instance as result of diarrhoea.
•Rehydration: correction of dehydration.
Characteristics of ORS:
1. Dry , homogeneously mix powder containing Dextrose, Sodium Chloride,
Potassium Chloride and either Sodium Bicarbonate or Sodium Citrate
2. May contain flavoring agent, but no artificial sweeteners are added
( saccharin and aspartame)

21. Composition of the formulation in terms of the amount, in g, to be dissolved in
sufficient water to produce 1000 ml.
The molar concentrations of sodium, potassium, chloride and citrate ions in terms
of millimoles per liter are given below:
The total osmolar concentration of the solution in terms of
mOsmol per liter is 245