Oral solutions for infantile gastroenteritis--variations in composition

Safety and effectiveness of homemade and reconstituted packet cereal-based oral rehydration solutions: a randomized clinical trial

OBJECTIVES

Parents may be deterred from obtaining commercial oral rehydration solutions (ORS) for their young children with acute diarrheal disease because of its availability and/or cost, especially if they are poor. We conducted a randomized clinical trial to determine 1) whether low-income parents could safely mix and administer cereal-based ORS (CBORS) both from ingredients commonly found in the home and from a premixed packet; 2) whether these CBORS were as effective in maintaining hydration as commercial glucose-based ORS; and 3) whether CBORS were more effective in reducing severity and duration of illness.

METHODS

Children 4 to 36 months of age discharged from emergency departments and health centers with acute diarrheal disease were randomized to receive either homemade CBORS, reconstituted packet CBORS, or Pedialyte. A study nurse saw the child at home each day until the illness resolved, and obtained capillary blood for serum sodium at enrollment and at 24 to 48 hours; a sample of CBORS for sodium concentration; stool for pathogen analysis; and daily fluid intake, stool frequency, and weight.

RESULTS

A total of 232 children were enrolled, of whom 203 (88%) completed the study. Two parents (3%) in the homemade CBORS group and one parent (1%) in the packet CBORS group made mixing errors resulting in a high sodium concentration (>100 mEq/L); their children refused the solution and had normal serum sodium values. Mean CBORS sodium concentration for the remainder of the homemade CBORS group was 60 +/- 10 mEq/L, and for the packet CBORS group, 54 +/- 13. Eighteen children (11%) had abnormal serum sodium values at presentation, which returned to normal in all groups in most cases. Three children (4.5%) in the homemade CBORS group, 4 (6%) in the packet CBORS group, and 1 child (1.4%) in the Pedialyte group failed therapy. Children refused to take homemade CBORS and packet CBORS (43% and 32%, respectively) more often than Pedialyte (9%), and those in the CBORS groups tended to take less ORS and total fluids. There were no significant differences among the three groups in incidence of daily vomiting or stooling, duration of diarrhea, or weight gain.

CONCLUSIONS

CBORS do not offer a clinically significant advantage over glucose-based ORS. Homemade CBORS represent a treatment option in carefully selected cases, but it is not the safest alternative for regular clinical use.

Search for the ideal oral rehydration solution: studies in a model of secretory diarrhoea

In situ perfusion of whole rat small intestine was used to compare the efficacy of five oral rehydration solutions in promoting water and sodium absorption in normal intestine and secreting intestine after exposure to cholera toxin. Solutions varied in their sodium (35-90 mmol/l) and glucose (111-200 mmol/l) concentrations, molar ratio of glucose:sodium (1.2-5.8), and osmolality (281-331 mOsmol/kg), and contained either bicarbonate (18-30 mmol/l) or citrate (10 mmol/l). In normal intestine all solutions promoted net water absorption. Cholera toxin induced reproducible water secretion but all solutions reversed this to absorption. Water absorption was greatest with solutions containing sodium 60 mmol/l and glucose 111 or 140 mmol/l, and with a glucose:sodium ratio approximately 2, in both normal and secreting intestine. All solutions promoted net glucose absorption in both normal and secreting intestine. Net sodium absorption occurred with solutions containing greater than or equal to 60 mmol/l sodium in normal intestine but sodium secretion occurred from all solutions in secreting intestine. Sodium movement was directly related to the sodium concentration of the solution and sodium secretion occurred despite net water and glucose absorption. We consider that these studies may guide future development of oral rehydration solutions.

Optimising oral rehydration solution composition for the children of Europe: clinical trials

Clinical trials testing different oral rehydration solutions (ORS) are reviewed. The effects of individual components and their concentrations are analysed in order to establish margins of safety for the composition of the ideal ORS for children in Europe. Glucose is the solute of choice for ORS and concentrations of 70-140 mmol/l are adequate. Glucose may be replaced by sucrose or glucose polymers. "Low" sodium concentrations (35-60 mmol/l) are advised for rehydration and maintenance in acute non-cholera diarrhoea, for children of all ages, including neonates, and for any degree of dehydration except shock. Although intended for children who are not malnourished, the European ORS should have an adequate potassium concentration (20-30 mmol/l), namely the same concentration as found in WHO-ORS. Chloride concentration depends upon other constituents of ORS, namely sodium and potassium, but the range of 30-90 mmol/l is considered to be adequate. Base or base precursors are not required for correction of acidosis except in the severe cases that always need intravenous replacement. A relatively low osmolality seems advisable.

Oral rehydration in infantile diarrhoea in the developed world

Acute diarrhoea is an important health problem in developed countries, particularly in young children. The attack rates for viral diarrhoea are similar in developed and developing countries. Rotavirus is the most common pathogen, followed by adenovirus. Bacterial diarrhoea is less common in developed than developing countries. The 2 most common bacterial pathogens are Campylobacter jejuni and Salmonella. The most serious consequence of diarrhoea is dehydration, and the treatment for this is the same whatever the pathogen. Recently, there have been major changes in the management of diarrhoea with emphasis on oral rehydration and early feeding. Two controversial areas are the sodium content of solutions designed for developed countries and the best route of administration of fluids to children with moderately severe dehydration. There have been 4 randomised controlled trials in developed countries comparing oral and intravenous rehydration. The findings have confirmed the experience in developing countries that most children without shock can be rehydrated orally, thus substantially reducing the need for intravenous fluids. It is important to give physiologically balanced solutions which contain 2% glucose and 50 to 90 mmol/L of sodium. Many of the commercially available oral solutions are appropriate for rehydration and maintenance of hydration in infants with diarrhoea of all types. They are recommended particularly for the prevention of dehydration in children of all ages with severe diarrhoea and for the treatment of dehydration. Children with mild diarrhoea and no dehydration can be given commercial clear fluids diluted with water, or homemade solutions made with table sugar and water. Salt must not be used. Babies should continue on breast milk or formula with extra water. Education is the key to successful oral rehydration, and the ultimate aim should be the prevention of dehydration.

High sugar worse than high sodium in oral rehydration solutions

The literature on oral sugar-electrolyte mixtures for treatment of acute diarrhoea is reviewed. Several trials have shown that the solution proposed by the WHO for developing countries containing inter alia 90 mmol/l of sodium and 111 mmol/l of glucose is safe for short term oral rehydration. When used in this manner there is no risk for development of hypernatraemia. The surplus base of the solution is not essential and, furthermore, other anions e.g. acetate may be substitute for bicarbonate. Other modifications of the WHO formula have also been successfully tried, e.g. sucrose 4% (117 mmol/l) instead of glucose 2% (111 mmol/l). A somewhat lower concentration of sucrose may, however, prove to be better. Most acute childhood diarrhoeas are not mediated by enterotoxin and thus not of the secretory type, but temporary malabsorption is common. Therefore, the amount of carbohydrate in oral sugar-electrolyte mixtures should be limited. Osmotic diarrhoea due to carbohydrate malabsorption is a more likely cause of hypernatraemia in dehydrated children than too much dietary sodium. In developed countries prepacked oral sugar-electrolyte mixtures are mainly designed for moderately sick children treated at home. There is no reason to raise the carbohydrate content of these mixtures above that of the WHO formula, but the sodium content must be lower. For most situations in home treatment 50 mmol/l of sodium will be adequate.