Oral rehydration without added bicarbonate for childhood gastroenteritis

Effect of bicarbonate, acetate, and citrate on water and sodium movement in normal and cholera toxin-treated rat small intestine

Bicarbonate, citrate, or acetate are commonly included in oral rehydration solutions to correct acidosis and possibly because of their ability to promote water and sodium absorption. We have investigated the effect of these anions on water and sodium transport in normal and also in secreting (cholera toxin-treated) rat small intestine using a single-pass perfusion technique. In normal jejunum bicarbonate and acetate produced net absorption, and citrate net secretion of both water and sodium. In normal ileum all anions produced net absorption of water and sodium. In the secreting jejunum, however, bicarbonate had no effect on water and sodium secretion, whereas acetate and citrate actually enhanced the secretory state for both water and sodium. None of these anions had any effect on water and sodium secretion in the ileum. These observations suggest that normal and secreting intestine are qualitatively different with regard to handling of these organic anions. The addition, therefore, of bicarbonate, acetate, or citrate to oral rehydration solutions may have no beneficial effect with regard to the promotion of water and sodium absorption in the secreting intestine during acute diarrhoeal states and could actually be deleterious.

Oral rehydration therapy without bicarbonate for prevention and treatment of dehydration: a double-blind controlled trial

Forty children (less than or equal to 2 years of age) were admitted to hospital with acute gastroenteritis and were randomly assigned to receive either an oral rehydration solution (ORS) containing bicarbonate (Na 35, K 20, Cl 37, HCO3 18, glucose 202 mmol litre-1) or an identical solution in which bicarbonate was replaced by chloride ions. Groups were matched for age, sex, ethnic origin, duration of diarrhoea and nutritional status. On admission, degree of dehydration, biochemical and haematological parameters were similar. The majority had minimal or no dehydration and only 30% had moderate to severe dehydration. All children were treated successfully with no complications. Oral rehydration solution intake by each group was similar. Clinical outcome, as judged by speed of rehydration or maintenance of hydration, duration of diarrhoea, stool frequency and length of hospital stay, was the same in both groups. After 24 h of ORS there was no difference between groups in venous pH, serum bicarbonate, urea and electrolytes. In hospitalized children with acute gastroenteritis in the United Kingdom an ORS without bicarbonate is a safe, effective means to prevent dehydration and maintain hydration and acid-base status where dehydration is not severe. Exclusion of bicarbonate would simplify production, increase stability and reduce the cost of ORS without apparent impairment of efficacy.