Major Extra and Intracellular electrolytes – Pharmaceutical Inorganic Chemistry B. Pharma 1st Semester

Major Extra and Intracellular electrolytes


• Body fluid compartments

• Electrolytes

• Hormones which regulates the electrolyte

• Functions of electrolytes

• Physiological role of acid, bases, buffers, sodium ion,
Chloride ion, bicarbonate ion, Phosphate ion, calcium ion, magnesium ion and
potassium ion

• Buffer system present in human body

• Metabolic acidosis and metabolic alkalosis

• Monograph analysis of compounds used as electrolyte


At the end of this
lecture, the student will be able to:

• Define electrolytes

• List, describe and compare the body fluid compartments

• Compare the compositions of intracellular and
extracellular fluids

• Identify the hormones that play important roles in
regulating fluid and electrolyte balance

• Describe the function of Electrolytes

• List the normal concentration of cations and anions
present in the body fluid compartments

• Describe the physiological role of sodium ion and
potassium ion

• Describe the physiological role of:

 Chloride ion

 Bicarbonate ion

 Phosphate ion

 Calcium ion

 Magnesium ion

• Calculate the amount of electrolyte in terms of

• Discuss the physiological role of acid and bases and

• Describe the different buffer system present in the body

• Define metabolic acidosis and metabolic alkalosis

• Explain the monograph analysis of:

 Sodium Chloride

 Potassium chloride

 Calcium Gluconate

 Oral dehydration salts


Electrolytes: Substances whose molecules dissociate into
ions when they are placed in water

Medically significant / routinely ordered electrolytes



Cation: Positively
Charged particles

Sodium (Na+)

Potassium (K+)

Calcium (Ca++)

Magnesium (Mg++)

Anion: Negatively
charged particles

Chloride (Cl-)

Bicarbonate (HCO3-)

Phosphate (HPO4-)

Composition of the Human Body

Fluids: Introduction

• Total amount of fluid in the human body is approximately
70% of body weight

Body fluid has been divided into two compartments:–

Intracellular fluid

• Inside the cells

• 55% of total body

Extracellular fluid

• Outside the cells

• 45% of total water body water

fluid includes

Interstitial fluid

Present between the cells

Approximately 80% of ECF


Present in blood

Approximately 20% of ECF

Also includes


Synovial fluid

Aqueous humor

Cerebrospinal fluid


Barriers separate ICF, interstitial fluid and plasma:

Plasma membrane:

Separates ICF from surrounding interstitial fluid

Blood vessel wall:

Separate interstitial fluid from plasma

Body Fluid
Compartments in human system

of body fluids

Inorganic substances

Organic substances

• Sodium

• Potassium

• Calcium

• Magnesium

• Chloride

• Phophate

• Sulphate

• Glucose

• Amino acids

• Fatty acids

• Hormones

• Enzymes


Methods of
fluid & electrolyte movement

• Diffusion

• Osmosis

• Active Transport

• Filtration


• Process by which a solute in solution moves

• Involves a gas or substance

• Movement of particles in a solution

• Molecules move from an area of higher concentration to an
area of lower concentration

• Evenly distributes the solute in the solution

For eg: diffusion of CO2 and O2 at respiratory epithelia


• Movement of the solvent or water across a membrane

• Involves solution or water

• Equalizes the concentration of ions on each side of

• Movement of solvent molecules across a membrane to an area
where there is a higher concentration of solute that cannot pass through the

Active transport system

• Moves molecules or ions uphill against concentration &
osmotic pressure

• Hydrolysis of adenosine triphosphate (ATP) provides energy

• Requires specific “carrier” molecule as well as specific
enzyme (ATPase)

• Sodium, potassium, calcium, magnesium, plus some sugars,
& amino acids use it


• Movement of fluid through a selectively permeable membrane
from an area of higher hydrostatic pressure to an area of lower hydrostatic

• Arterial end of capillary has hydrostatic pressure >
than osmotic pressure so fluid & diffusible solutes move out of capillary

involved Fluid balance and electrolyte balance

Fluid balance and electrolyte balance are mediated by three

• Antidiuretic hormone (ADH)

• Aldosterone

• Renin

ADH (Antidiuretic

• Produced in hypothalamus; water conservation hormone

• Stored in posterior pituitary gland

• Acts on renal collecting tubule to regulate reabsorption
or elimination of water

• If blood volume decreases, then ADH is released &
water is reabsorbed by kidney. Urine output will be lower but concentration
will be increased.


• Produced by adrenal cortex

• Released as part of RAA mechanism

• Acts on renal distal convoluted tubule

• Regulates water re absorption by increasing sodium uptake
from the tubular fluid into the blood but potassium is excreted

• Responsible for re absorption of sodium & water into
the vascular compartment


• Released by kidneys in response to decreased blood volume

• Causes angiotensinogen (plasma protein) to split &
produce angiotensin I

• Lungs convert angiotensin I to angiotensin II

• Angiotensin II stimulates adrenal gland to release
aldosterone & causes an increase in peripheral vasoconstriction

Functions in general:

• Volume and osmotic regulation

• Myocardial rhythm and contractility

• Cofactors in enzyme activation

• Regulation of ATPase ion pumps

• Acid-base balance

• Blood coagulation

• Neuromuscular excitability

• Production of ATP from glucose

plasma range of Electrolytes


Major cations inside
the cell (ICF) include

• Sodium (Na)

• Potassium (K)

• Magnesium (Mg)

Major cations outside
the cell (ECF) include

• Sodium (Na)

• Potassium (K)

• Calcium (Ca)

• The concentration of cations inside the cell and outside
the cell differs as shown  in figure on
the right e.g. there is much  higher
concentration of potassium in the ICF than in the ECF,  there is much higher concentration of sodium
in the ECF than in the ICF.


Major Anions inside
the cell (ICF) include

• Chloride (Cl)

• Proteins

• Phosphates (HPO4)

• Bicarbonate (HCO3)

• SO4

Major Anions outside
the cell (ECF) include

• Chloride (Cl)

• Proteins

• Phosphates (HPO4)

• Bicarbonate (HCO3)

• SO4

• The concentration of anions inside the cell and outside
the cell differs as shown in figure on the right e.g. there is much higher
concentration of proteins and Phosphate in the ICF than in the ECF,  there is much higher concentration of
chloride in the ECF than in the ICF

Cations and
Anions in Body Fluids

• Despite the differences in the concentration of specific
substances, the ICF and ECF osmotic concentrations are identical

• If the cell membrane were freely permeable, diffusion
would continue until these ions were evenly distributed across the membrane


• Range 135 – 145 mEq /L in serum

• Total body volume estimated at 40 mEq/kg

• 1/3 fixed to bone, 2/3 extracellular and available for
Trans membrane exchange

• Normal daily requirement 1-2 mEq/kg/day

• Chief extracellular cation about 90%

Food Sources

High Sodium

Low Sodium


Corned beef



Potato chips



Soda crackers

Tomato juice

Beef cubes


Decaffeinated coffee





Unsalted grains




Shredded wheat

Fresh meats



Sodium function

•Transmission and conduction of nerve impulses

•Responsible for osmolality of vascular fluids

•Regulation of body fluid levels

•Sodium shifts into cells and potassium shifts out of the
cells (sodium pump)

•Assists with regulation of acid-base balance by combining
with Cl- or HCO3 to regulate the balance

Clinical Features:

• IF serum sodium ions is < 135 mmol/L Hyponatremia

•Increased Na+ loss

• Aldosterone deficiency

• Addison’s disease (hypo-adrenalism, result in desearsed

• Diabetes mellitus

• In acidosis of diabetes, Na is excreted with ketones

• Potassium depletion

• K normally excreted, if none, then Na

• Loss of gastric contents

manifestations of Hyponatremia

• Neurological symptoms: Lethargy, headache, confusion,
apprehension, depressed, reflexes, seizures and coma

• Muscle symptoms: Cramps, weakness, fatigue

• Gastrointestinal symptoms: Nausea, vomiting, abdominal
cramps and diarrhoea

Hypernatremia: Serum
Sodium exceeds 145 meq/liter

Clinical Features: Hypertonic IV solution

• Oversecretion of aldosterone

• Loss of pure water

• Long term sweating with chronic fever

• Respiratory infection → water vapor loss

• Diabetes – polyuria

• Insufficient intake of water ( hypodipsia hypodipsia)

Cushing’s syndrome
– opposite of Addison’s

manifestations of Hypernatremia

• Thirst

• Lethargy (Lack of energy)

• Neurological dysfunction due to dehydration of brain cells

• Decreased vascular volume

Treatment of

• Lower serum Na+

• Isotonic salt -free IV fluid

• Oral solutions preferable

ions( K+)

Potassium normal values

Serum (adults) – 3.5 – 5.3 mEq/L

Newborns slightly higher – 3.7 – 5.9 mEq/L

• Range 3.5 – 5.0 mEq mEq/L in serum

• Total body volume estimated at 50 mEq/kg

• 98% intracellular concentration of 150 mEq mEq/L

• Extracellular concentration of 70 mEq/L

• Normal daily requirement 0.5 – 0.8 mEq/kg/day

• Chief intracellular cation

Potassium Function:

• Most abundant intracellular cation

 Necessary for transmission and conduction of nerve

• Maintenance of normal cardiac rhythm

 Necessary for smooth and skeletal muscle contraction

Food sources –
veggies, fruits, nuts, meat

Causes of Hypokalemia

• Increased K+ loss

• Chronic diuretics

• Acid/base imbalance

• Trauma and stress

• Increased aldosterone

• Redistribution between ICF and ECF

• Hepatic disease

• Acute alcoholism

manifestations of Hypokalemia

• Neuromuscular disorders

• Weakness, flaccid paralysis, respiratory arrest,

• Dysrhythmias: appearance of U wave

• Postural hypotension

• Cardiac arrest

Treatment: Increase
K+ intake, but slowly, preferably by foods


• Serum K+ > 5.5 mEq / L

• Check for renal disease

• Massive cellular trauma

• Insulin deficiency

• Addison Addison’s disease

• Potassium sparing diuretics

• Decreased blood pH

• Exercise causes K+ to move out of cells

Treatment of

If time, decrease intake and increase renal excretion

• Insulin + glucose

• Bicarbonate

• Ca++ counters effect on heart


– The normal adult value for chloride is 97-107 mEq/L.

– Chloride is the major extracellular anion

– Moves relatively easily between ECF and ICF because most
plasma membranes contain Cl

– Leakage channels and antiporters

– Can help balance levels of anions in different fluids

• Chloride shift in RBCs

– Regulated by

• ADH – governs extent of water loss in urine

• Processes that increase or decrease renal reabsorption of
Na+ also affect reabsorption of Cl-

• Chloride is an important electrolyte

• Maintains body’s metabolism

• Maintains water balance, acid-base balance, aids in
digestion (hydrochoric acid) & osmotic pressure (with Na and H20) Combines
with Na to form salts

• Regulated by kidneys

Source of foods – Citrus fruits, Salt

Clinical features:

Hyperchloremia (increased plasma Cl concentration)

• Serum level > 106mEq/

Causes of

May include:

• Loss of body fluids from prolonged vomiting, diarrhea,
sweating or high fever (dehydration).

• High levels of blood sodium.

• Kidney failure, or kidney disorders

• Diabetes insipidus or diabetic coma

• Drugs such as: androgens, corticosteroids, estrogens, and
certain diuretics

restore fluid & electrolyte balance

Symptoms of

•Many people do not notice any symptoms of hyperchloremia,
unless they are experiencing very high or very low levels of chloride in their

•Dehydration, fluid loss, or high levels of blood sodium may
be noted.

•Diarrhea, or vomiting when suffering from hyperchloremia

•Arrhythmias, decreased cardiac output, muscle weakness, LOC
changes, Kussmauls’s respirations

Clinical features:

Hypochloremia (decreased plasma Cl concentration)

 Serum level 96mEq/L

 Results from prolonged vomiting & suctioning

 Is observed in salt-losing nephritis as associated with
chronic pyelonephritis

diet/IV therapy

Causes of
hypochloremia may include:

•Loss of body fluids from prolonged vomiting, diarrhea,
sweating or high fevers

•Drugs such as: bicarbonate, corticosteroids, diuretics, and

Symptoms of

• Dehydration, fluid loss, or high levels of blood sodium
may be noted

• Diarrhea, or vomiting

• Metabolic alkalosis

• Nerve excitability

• Muscle cramps

• Twitching

• Hypoventilation

• Decreased BP if severe

Phosphate   PO4-

• Principal anion of intracellular fluid compartment

• Plasma 1.7-2.6 mEq/liter

• Phosphate (H2PO4 -, HPO42-, PO4 3-)

• Most (85%) is stored in bone as calcium salts

• Also combined with lipids, proteins, carbohydrates,
nucleic acids (DNA and RNA), B vitamin synthesis

• High energy phosphate transport compound

• Important acid-base buffer in body fluids

Source of foods:
Dairy product, meats, poultry, fish, egg, nuts.

Function of

•Involved in acid–base buffering system, ATP production, and
cellular uptake of glucose

•Maintenance requires adequate renal functioning

•Essential to muscle, RBCs, and nervous system function

Clinical features:

• Serum level < 1.8mEq/L

• Results from decreased intestinal absorption and increased

• S/S bone & muscle pain, mental changes, chest pain,
respiratory failure

Treatment: Diet/
IV therapy


– Oral supplementation

– Ingestion of foods high in PO43-

– IV administration of sodium or potassium phosphate

Clinical features:

• Serum level> 2.6mEq/L

• Results from renal failure, low intake of calcium

• S/S: neuromuscular changes (tetany), EKG changes,

Treatment: Diet;
hypocalcemic interventions   Medications:
phosphate binding

• The body can tolerate hyperphosphatemia fairly well BUT
the accompanying hypocalcemia is a larger problem!


– Identify and treat underlying cause

– Restrict foods and fluids containing PO43-

– Adequate hydration and correction of hypocalcemic


• Bicarbonate 22-28 mEq/L

• Second most prevalent extracellular anion

• Principle buffer of body pH. (Extracellular)

• Neutralizes acids

• Plays important role in acid / base balance

• Acts as chemical sponge to soak up Hydrogen ions

• (Acidic metabolic waste) for every one Hydrogen ion twenty
bicarbonate ions are released to maintain balance


 Bicarbonate is regulated by secretion / reabsorption of
the renal tubules

Acidosis : ↓ renal excretion

Alkalosis : ↑ renal excretion

 Kidney regulation requires the enzyme carbonic anhydrase –
which is present in renal tubular cells & RBCs carbonic anhydrase

Reaction: CO2 + H2O H2CO3 H+
+ HCO3–

Clinical Significance:

• Alterations of HCO3- and CO2 dissolved in
plasma are characteristic of acidbase imbalance

• When acid-base imbalance is suspected, evaluation of blood
gases and pH is required

– Increase in CO2 occur in metabolic alkalosis due to:

eg: severe vomiting,hypokalemic states

– Decrease in CO2 are seen in: eg: renal failure

Calcium Ca++

• In body fluids mainly an extracellular cation

• Most abundant in body but: 99% in teeth and bones

• Needed for nerve transmission, vitamin B12 absorption,
muscle contraction & blood clotting

• Inverse relationship with Phosphorus

• Vitamin D needed for Calcium absorption

• The most abundant mineral in the human body

Food sources for
calcium ions

Dairy foods: Milk, yogurt, cheese

Leafy green vegetables: Broccoli, kale, spinach

Fruits: Oranges

Beans and peas: Tofu, peanuts, peas, black beans, baked

Fish: Salmon, sardines

Miscellaneous: Sesame seeds, blackstrap molasses, corn
tortillas, almonds, brown sugar

How it functions in
body metabolism

• 99% of total body calcium is stored in the bones and teeth

• 1% is found throughout the body in blood, muscle, and the
fluid between cells

 45% circulates as free Ca ions

 40% bound to albumin

 15% bound to anions

• Ionized calcium is usually a more sensitive and specific
for calcium disorders

function of calcium ions

• The normal transmission of nerve impulses

• Calcium flows into nerve cells and stimulates the release
of molecules called neurotransmitters

• The role in muscle contraction

• Healthy blood pressure

• The initiation of blood clotting and

• The regulation of various hormones and enzymes

function of calcium ions

Can it be synthesized by the human body or must it come from
other sources

• Body needs calcium to build and maintain strong bones and

• Absorb calcium every day from dietary intake because body
does not make calcium

Clinical Features:

• Serum Calicum < 4.3mEq/L

• Results from low intake, loop diuretics, parathyroid
disorders, renal failure

• Treatment: diet/IV therapy

• What are some
medical conditions that may cause hypocalcemia?

Hypoparathyroidism (low PTH levels = decreased release of Ca
from bones)

S/P thryoid surgery (low Calcitonin = decreased release of
Ca from bones)

Acute pancreatitis

Crohns Disease (inflammatory bowel disease)

Hyperphosphatemia (ESRF)

• What are some other
conditions that might cause low Ca?

GI losses – nasogastric suctioning, vomiting, diarrhea

Long term immobilization

Lactose intolerance

• If hypocalcemia is
prolonged, the body will utilize stored Ca from bones. What complication might

Fractures (late sign)

Treatment of

Calcium, Vitamin D

Clinical Features:

• Serum Ca > 5.3mEq/L

• Results from hyperparathyroidism, some cancers, prolonged

• S/S muscle weakness, renal calculi, fatigue, altered LOC,
decreased GI motility, cardiac changes

• Treatment: medication/ IV therapy

• What are some
medical conditions that may cause hypercalcemia?

Hyperparathyroidism (high PTH levels = increased release of
Ca from bones)

Paget ’s disease

Some Cancers – Multiple Myleoma

Chronic Alcoholism (with low serum phosphorus)

• What are some other
conditions that might cause low Ca?

Excessive intake of Ca OR Vitamin D

Excessive intake of OTC antacids

If hypercalcemia is
uncorrected, AV block and cardiac arrest may occur

Mg 2+

• The eighth most abundant element in the earth’s crust

• Body concentration: 1.5-2.5mEq/L

• Most located within ICF

• Needed for activating enzymes, electrical activity,
metabolism of proteins, DNA synthesis

• Regulated by intestinal absorption and kidney

• Magnesium plays important roles in the structure and the
function of the human body

Food Sources for
magnesium ion

• Green vegetables such as spinach because the center of the
chlorophyll molecule (which gives green vegetables their color)

• Legumes (beans and peas)

• Nuts and seeds

• Unrefined grains

• Tap water (varies according to the water supply)

How it functions in
body metabolism

• Activates more than 300 enzymes (energy related)

• Regulates (Ca, K, and Na) transmission of nerve impulses.
Calcium contract muscles and magnesium relax muscles

• Ensures proper DNA and RNA formation and function

• Facilitates PTH secretion

• Helps to regulate blood sugar levels, promotes normal
blood pressure

• Involve in energy metabolism and protein synthesis

Metabolism of
magnesium ion in the body

• Healthy individuals absorbs 40-60% magnesium consumed

• Absorption enhanced by calcium, phosphorus and fat

• Long term storage in the bones

• Kidney is the organ regulate magnesium homeostasis

• 90% of filtered magnesium is reabsorbed by the kidneys in
response to salt and H2O reabsorption

Can it be synthesized
by the human body or must it come from other sources

• Magnesium is a mineral, so therefore just like calcium,
magnesium must be absorbed through dietary intake

• 50% of total body magnesium is found in bone

• The other half is found predominantly inside cells of body
tissues and organs

• Only 1% of magnesium is found in blood, but the body works
very hard to keep blood levels of magnesium constant

Clinical Features:

• Serum < 1.5mEq/L

• Results from decreased intake, prolonged NPO status,
chronic alcoholism & nasogastric suctioning

• S/S: muscle weakness, cardiac changes, mental changes,
hyperactive reflexes & other hypocalcemia S/S

• Treatment: replacement IV therapy restore normal Ca levels
(Mg mimics Ca) seizure precautions

Clinical Features: Hypermagnesemia

• Serum>2.5mEq/L

• Results from renal failure, increased intake

• S/S: Flushing, lethargy, cardiac changes (decreased HR),
decreased respiratory, loss of deep tendon reflexes

• Treatment: Restrict intake,diuretic

Concentration for
expressing electrolytes:

The concentration of electrolytes in solution is expressed
in terms of milli equivalents (mEq)

• Refers to the chemical activity of an electrolyte

• Is related to the total number of ionic charges in
solution and considers the valence (charge) of each ion

• For a given chemical compound, the milli equivalents of
cations equals that of anions

Example: a solution of NaCl will contain the same number of
milliequivalents of Na+ (the cation) as it will Cl- (the anion)

• There is a trend to shift from using mEq to using mg of
the given ion

• Beware that this can be confusing! They are not
EQUIVALENT!!! And mg of a given ion is not equivalent to mg of the compound

For example:  mEq
CaCl2 is not equal to mg CaCl2 which is not equal to mg Ca ion

equivalents Formula:

• mEq =
represents amount in milligrams, of a solute equal to 1/1000 of its gram
equivalent weight taking into account the valence of the ions.

mEq = mg x
valence / atomic, molecular or formula weight

mg = mEq x
atomic, molecular or formula weight / valence

Equivalent weight =
formula weight divided by the total valence

Equiv Weight (g) =
atomic, molecular or formula weight / valence

Acids and
Bases and Buffers

• Acids– Release
H+ into solution

• Bases– Remove
H+ from solution

• Acids and bases–
Grouped as strong or weak

• Buffers: Resist
changes in pH

– When H+ added, buffer removes

– When H+ removed, buffer replaces

• Types of buffer

– Carbonic acid/bicarbonate

– Protein

– Phosphate


The importance of pH

• The pH of the ECF remains between 7.35 and 7.45

– If plasma levels fall below 7.35 (acidemia), acidosis

– If plasma levels rise above 7.45 (alkalemia), alkalosis

– Alteration outside these boundaries affects all body

e.g. can result in coma, cardiac failure, and circulatory

of blood pH

• The lungs and kidneys play important role in regulating
blood pH

• The lungs regulate pH through retention or elimination of
CO2 by changing the rate and volume of ventilation

• The kidneys regulate pH by excreting acid, primarily in
the ammonium ion (NH4+), and by reclaiming HCO3- from the glomerular filtrate
(and adding it back to the blood)

of pH control

• Buffer system consists of a weak acid and its anion

• Three major buffering systems:

– Carbonic acid-bicarbonate

• Buffers changes caused by organic and fixed acids

– Protein buffer system

• Amino acid

– Hemoglobin buffer system

• H+ are buffered by hemoglobin

Acid-Bicarbonate Buffering System

• Carbonic acid-bicarbonate buffer system

– CO2 + H2O ßà H2CO3 ßà H+ + CO3

• Has the following limitations:

– Cannot protect the ECF from pH changes due to increased or
depressed CO2 levels

– Only functions when respiratory system and control centers
are working normally

– It is limited by availability of bicarbonate ions
(bicarbonate reserve)

buffer system

H2CO3 + H2O ↔ H3O+ + HCO3

• Excess acid (H3O+) in the body is neutralized by HCO3-

• H2CO3 + H2O ← H3O+ + HCO3

Equilibrium shifts left

• Excess base (OH-) reacts with the carbonic acid (H2CO3)

• H2CO3 + OH- → H2O + HCO3-

Equilibrium shifts right

buffer system

• Proteins contain – COO groups, which, like
acetate ions (CH3COO), can act as proton acceptors.

• Proteins also contain – NH3+ groups, which,
like ammonium ions (NH4+), can donate protons.

• If acid comes into blood, hydronium ions can be
neutralized by the – COO groups

– COO + H3O+ → – COOH + H2O

• If base is added, it can be neutralized by the – NH3+

– NH3+ + OH→ – NH2 + H2O

buffer system

• The phosphate buffer system (HPO42-/H2PO4)
plays a role in plasma and erythrocytes.

H2PO4 + H2O ↔ H3O+ + HPO42-

• Any acid reacts with monohydrogen phosphate to form
dihydrogen phosphate

H2PO4 + H2O ← HPO42- + H3O+

• The base is neutralized by dihydrogen phosphate

H2PO4 + OH→ HPO42- + H3O+

excretion of H+

– Metabolic reactions produce nonvolatile acids

– One way to eliminate this huge load is to excrete H+
in urine

– In the proximal convoluted tubule, Na+ /H+ antiporters
secrete H+ as they reabsorb Na+

– Intercalated cells of collecting duct include proton pumps
that secrete H+ into tubule fluid

– Urine can be up to 1000 times more acidic than blood

– 2 other buffers can combine with H+ in collecting duct

• HPO42- and NH3


– Normal pH range of arterial blood 7.35-7.45

• Acidosis – blood pH below 7.35

• Alkalosis – blood pH above 7.45

– Major physiological effect of

• Acidosis – depression of synaptic transmission in CNS

• Alkalosis – overexcitability of CNS and peripheral nerves


• Results from changes in HCO3 concentration

– Metabolic acidosis – abnormally low HCO3 in
systemic arterial blood

• Loss of HCO3 from severe diarrhea or renal

• Accumulation of an acid other than carbonic acid – ketosis

• Failure of kidneys to excrete H+ from
metabolism of dietary proteins

• Hyperventilation can help

• Administer IV sodium bicarbonate and correct cause of

Clinical Features:
Metabolic acidosis

– Abnormally high HCO3 in systemic arterial

• Nonrespiratory loss of acid – vomiting of acidic stomach
contents, gastric suctioning

• Excessive intake of alkaline drugs (antacids)

• Use of certain diuretics

• Severe dehydration

• Hypoventilation can help

• Give fluid solutions to correct Cl, K+
and other electrolyte deficiencies and correct cause of alkalosis

of Sodium chloride

Name: sodium

Chemical formula:

Molecular weight:

Standards: Sodium
Chloride contains not less than 99.0 per cent and not more than 100.5 per cent
of NaCl, calculated on the dried basis

Synonyms: common

Method of

Industrially, Laboratory

Industrially: By the evaporation of sea water

Laboratory: By neutralization process

Chemical reaction:

NaOH + HCl à
NaCl + H2O

Properties of Sodium


 White or colourless crystals or a white crystalline powder

Solubility: Freely soluble in water

Test for purity

•Appearance of solution

•Acidity or alkalinity




•Loss on drying

•Calcium and magnesium


• Heavy metals

• Barium


Assay Principle

Precipitation titration, Modified Volhards Method

Nitrobenzene /dilute HNO3

NaCL + AgNO3 ————————————-à AgCl + NaNO3 + AgNO3


NH4SCN + AgNO3 à  AgSCN + NH4NO3


NH4SCN + Ferric alum à Ferric thiocyanate

Storage: Store
protected from light

Medicinal uses:

•Manufacturing dialysis fluid

•Electrolytic replenisher

•Common Salt

of Potassium chloride

Name: Potassium

Chemical formula:

Molecular weight:

Potassium Chloride contains not less than 99.0 per cent and not more than 100.5
per cent of KCl, calculated on the dried basis

Synonyms:  Sylvine, sylvite

Method of

It is prepared by neutralization of potassium hydroxide and
hydrochloric acid

KOH + HCl à KCl + H2O

Properties of
Potassium chloride:

Description: Colourless,
Elongated, Prismatic or Cubical crystals or White granular powder, Odourless

Freely soluble in water; insoluble in ethanol

Test for purity


•Appearance of solution


•Heavy metals



•Calcium and magnesium


• Barium

•Loss on Drying

•Acidity or alkalinity

Assay Principle

Precipitation titration, Mohr’s Method

KCL + AgNO3 à AgCl + KNO3

Potassium chromate

Colour change:
Yellow to Brick red

Storage: Store
protected from moisture

Medicinal uses:

•Seasoning agent

•Electrolytic replenisher

•Gelling agent

•Yeast food

of Calcium Gluconate

Name: Calcium

Chemical formula:
C12H22CaO14. H2O

Molecular weight:

Calcium gluconate contains not less than 98.0 per cent and not more than 102.0
per cent of calcium gluconate, calculated on the dried basis

Properties of Calcium
gluconate :

Description: Colourless
or White granular powder, Crystalline, Odourless, Stable in air

Freely soluble in boiling water; insoluble in ethanol, chloroform and ether

Assay of
calcium gluconate

Buffer: Ammonia
and ammonium chloride solution

Modarant Black II

Colour change:
Pink – blue

Storage: Store
protected from moisture

Medicinal uses:


•Electrolytic replenisher

Rehydration Salts

Name: Oral
Rehydration Salts

Standards: Oral
Rehydration Salts contain not less than 90.0 per cent and not more than 110.0
per cent of the stated amount of Dextrose (anhydrous) or Dextrose Monohydrate
(as appropriate) and of the requisite amounts of sodium, Na, potassium, K,
chloride, Cl, and citrate, C6H5O7, calculated from the stated amounts of the
relevant constituents.

ORS Powder

Oral Rehydration Salts are dry, homogeneously mixed powders
containing Dextrose, Sodium Chloride, Potassium Chloride and either Sodium
Bicarbonate or Sodium Citrate for use in oral rehydration therapy after being
dissolved in the requisite amount of water


•Store protected from moisture in sachets, preferably made
of aluminium foil,

•containing sufficient powder for a single dose or for a
day’s treatment or

•for use in hospitals, in bulk containers containing
sufficient quantity to produce a volume of solution appropriate to the daily
requirements of the hospital concerned

Labelling. The label

(1) For sachets, the total weights, in g, of each

(2) For bulk containers, the weights, in g, of each
constituent in a stated quantity, in g, of the oral powder

(3)The molar concentration in millimoles per litre of
sodium, potassium, chloride and citrate ions, and of dextrose as well as the
total osmolar concentration in mOsmol per litre of the solution prepared from
the oral powder

(4) The total weight of the contents of the container

(5) The directions for use

(6) That any portion of the solution prepared from the oral
powder that remains unused for 24 hours after preparation should be discarded

(7) The storage conditions

Properties of ORS:

Description: white
to creamy-white, amorphous or crystalline powder, odourless

Freely soluble in water

Test for purity

•Uniformity of weight

•Seal test

•Other test as per oral powders

Medicinal uses:

•Maintaining acid base balance in body fluid

•Electrolytic replenisher


•The compositions of intracellular and extracellular fluids

•The movement of fluid that takes place within the ECF,
between the ECF and the ICF, and between the ECF and the environment

•The hormones play important role in regulating fluid and
electrolyte balance

Electrolytes play a major role in the body fluid
compartments: Osmotic regulation, myocardial, acid base balance, blood

The cations:
Sodium, potassium, magnesium

The anion:
Chloride, phosphate, bicarbonate, sulphate

• Sodium: Major
cat ion found in ECF

Function: Nerve impulses, sodium potassium pump.

Deficiency: Hyponatraemia – Sodium ions replacement

Hypernatraemia-Less sodium content

• Potassium:
Higher concentration in the ICF

Maintains intracellular, functioning of excitable cells

Deficiency: Hypokalaemia -Replacement of potassium ions

Hyperkalaemia- Insulin + glucose, bicarbonate

• Chloride: The
major extracellular anion, 97-107 mEq/L,regulated by ADH,maintains body
metabolism, water and acid base balance, mainly with sodium ions

Deficiency: Hyperchloremia:Serum level > 106mEq/L

Treatment: restore fluid & electrolyte balance

Hypochloremia: Serum level > 106mEq/L

Treatment: restore fluid & electrolyte balance

• Phosphate PO4- :
Plasma 1.7-2.6 mEq/liter, important acid-base buffer in body fluids


Hypophosphatemia: Serum level < 1.8mEq/L

Treatment: Diet/ IV therapy

Hyperphosphatemia Serum level> 2.6mEq/L

Treatment: Diet; hypocalcemic interventions

Medications: phosphate binding

• Bicarbonate:
Second most prevalent extracellular anion, 22-28mEq/L concentration, principle
buffer of the body pH

• Change in the concentration of bicarbonate ions can form
metabolic acidosis and metabolic alkalosis

• Calcium: Mainly
an extracellular cation —4.5-5.5mEq/L,99% of total body calcium is stored in
the bones and teeth,1% is found throughout the body in blood, muscle, and the
fluid between cells.

Function: Nerve impulses, releases neurotransmitters, muscle
contraction, blood clotting, regulation of blood clotting

Deficiency: Hypocalemia: Serum calcium < 4.3mEq/L,

Treatment: diet and IV therapy

Hypercalcemic: Serum Ca > 5.3mEq/L,

Treatment: Medication / IV therapy

• Magnesium:
1.5-2.5mEq/L, located within ICF

– Function: For activating enzymes, electrical activity,
metabolism of proteins, DNA synthesis

– Deficiency : Hypomagnesemia: Serum < 1.5mEq/L

Treatment: Replacement/ IV therapy

Hypermagnesemia: Serum>2.5mEq/L

Treatment: Restrict intake, diuretic 

• Milli equivalents:
Represents amount in milligrams, of a solute equal to 1/1000 of its gram
equivalent weight taking into account the valency of the ions

• Acids: Release
H+ into solution

Bases: Remove H+ from solution

• Buffers: Resist
changes in pH

• Types of buffer

– Carbonic acid/bicarbonate

– Protein

– Phosphate

• Metabolic acidosis
abnormally low HCO3- in systemic arterial blood

• Metabolic
Abnormally high HCO3- in systemic arterial blood

•Sodium chloride:
Commonly known as common salt, is prepared by evaporation of sea water, assayed
by modified Volhards method and medicinally used as electrolyte replenisher and
in the preparation of isotonic solution

•Potassium chloride:
Prepared by neutralising potassium hydroxide with Hydrochloric acid, assayed by
Mohr’s method and medicinally used as electrolyte replenisher, gelling agent,
adsorbent and yeast food

Calcium gluconate:
Prepared by treating gluconic acid with calcium carbonate, used in the
treatment of calcium deficiency

• ORS: Available
in the form of sachets with different flavours, used for maintaining acid base


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