PH2.2 Prepare oral rehydration solution from ORS packet and explain its use.
Oral rehydration solution (ORS) is a liquid preparation made from salt mixture of glucose,
sodium chloride, potassium chloride & Sodium Citrate.
After being dissolved in the requisite volume of water they are intended for the prevention
& treatment of dehydration. Dehydration is the reduction in circulatory blood volume and
can be diagnosed based on physical signs and clinical symptoms and can be classified as mild
and severe.
Signs and Clinical Symptoms Mild Severe
1 Patient’s appearance Thirsty and alert Sweaty and drowsy
2 Pulse Normal rate and volume Rapid & feeble
3 Blood pressure Normal Less or unrecordable.
4 Skin elasticity Pinch retracts immediately Pinch retracts slowly
5 Tongue Moist Dry
Causes of Dehydration
1) Excessive fluid loss as seen in gastroenteritis, diarrhoea, vomiting;
2) Inadequate water intake as seen in oesophageal obstruction, water deprivation or lack of
thirst
Types of ORS
1) Standard WHO ORS (Old- Osmolarity 311 mOsm/Litre )
2) New formula WHO ORS (Low Osmolarity ORS- 245 mOsm/Litre )
3) Resomal (Rehydration solution for Malnutrition)
4) Cereal based ORS
5) Home made ORS
New Formula WHO ORS (Low Osmolarity)
Component Chemical formula Concerntration gm/L
Sodium Chloride NaCl 2.6 gm
Potassium Chloride KCl 1.5 gm
Trisodium Citrate C6H5Na3O7 2.9 gm
Anhydrous Glucose C6H12O6 13.5 gm
Water H2O 1L
Concentration yielded after dissolution in 1 litre drinking water.
Component Concerntration
Sodium 75 mOsm/Litre
Glucose 75 mOsm/Litre
Chloride 65 mOsm/Litre
Potassium 20 mOsm/Litre
Citrate 10 mOsm/Litre
Total Osmolarity 245 mOsm/Litre
Low Osmolarity ORS due to reduction in glucose as compared to older preparations
causes reduction in stool output, decrease in vomiting and decrease in use of I.V
fluids without increasing risk of hyponatremia.
For this reason, the recommendation for use of Standard WHO ORS was changed to
low osmolarity ORS.
GENERAL PRINCIPLE OF ORS
1) It should be isotonic or somewhat hypotonic to plasma i.e. total osmolarity 200-310
mOsm/Litre for all ages and all types of diarrhoea.
2) Zinc supplementation along with low osmolarity ORS reduces the duration, severity and
risk of recurrence of acute diarrhoea episodes in children below 5 years of age.
3) Glucose facilitates absorption of sodium (and hence water) on a 1:1 molar basis in the
small intestine.
4) Sodium and Potassium are needed to replace losses of essential ions during diarrhoea.
5) Citrates correct acidosis resulting from dehydration.
Indications of ORS
1. To prevent or treat dehydration due to diarrhoea.
2. Post-surgical, Post burn & post trauma maintenance of Hydration & nutrition in
place of I.V infusion.
3. Heat stroke
4. During changeover from I.V to enteral alimentation
Contraindications of ORS
1. Signs of dehydration worsen despite giving ORT.
2. Persistent vomiting despite proper administration of ORT
3. comatose or unconscious
4. Proven or suspected intestinal obstruction or ileus.
EXERCISE
Q. What is composition of WHO recommended low osmolarity ORS?
Q. What are the functions of each ORS ingredients?
Q. Write general guidelines for ORS administration after each loose stool for different age
groups?
Q. What are the advantages of new reduced osmolarity ORS ?
Q. How is Homemade oral rehydration solution prepared?
Q. How long can oral rehydration solution be used after preparation?
