Hypotonic oral rehydration solution in acute diarrhoea: a controlled clinical trial

Issues and Controversies in the Evolution of Oral Rehydration Therapy (ORT)

The original studies demonstrating the efficacy of oral glucose-electrolytes solutions in reducing or eliminating the need for intravenous therapy to correct dehydration caused by acute watery diarrheas (AWD) were focused chiefly on cholera patients. Later research adapted the oral therapy (ORT) methodology for treatment of non-cholera AWDs including for pediatric patients. These adaptations included the 2:1 regimen using 2 parts of the original WHO oral rehydration solution (ORS) formulation followed by 1 part additional plain water, and a “low sodium” packet formulation with similar average electrolyte and glucose concentrations when dissolved in the recommended volume of water. The programmatic desire for a single ORS packet formulation has led to controversy over use of the “low sodium” formulations to treat cholera patients. This is the subject of the current review, with the conclusion that use of the low-sodium ORS to treat cholera patients leads to negative sodium balance, leading to hyponatremia and, in severe cases, particularly in pediatric cholera, to seizures and other complications of sodium depletion. Therefore it is recommended that two separate ORS packet formulations be used, one for cholera therapy and the other for non-cholera pediatric AWD.

The management of acute diarrhea in children in developed and developing areas: from evidence base to clinical practice

INTRODUCTION

Acute diarrhea remains a major problem in children and is associated with substantial morbidity, mortality and costs. While vaccination against rotavirus could reduce the burden of the disease, the persistent impact of intestinal infections requires effective treatment in adjunct to oral rehydration solutions, to reduce the severity and duration of diarrhea. Several therapeutic options have been proposed for acute diarrhea, but proof of efficacy is available for few of them, including zinc, diosmectite, selected probiotics and racecadotril. However, at present there is no universal drug, and therapeutic efficacy has only been shown for selected drugs in selected settings, such as: outpatients/inpatients, developed/developing countries and viral/bacterial etiology.

AREAS COVERED

This narrative review reports the opinions of experts from different countries of the world who have discussed strategies to improve the management of diarrhea.

EXPERT OPINION

More data are needed to optimize the management of diarrhea and highlight the research priorities at a global level; such priorities include improved recommendations on oral rehydration solution composition, and the reevaluation of therapeutic options in the light of new trials. Therapeutic strategies need to be assessed in different settings, and pharmacoeconomic analyses based on country-specific data are needed. Transfer to clinical practice should result from the implementation of guidelines tailored at a local level, with an eye on costs.

Oral rehydration solutions in non-cholera diarrhea: a review

The use of oral rehydration solution (ORS) has revolutionized the management of acute diarrhea. The implementation of the standard World Health Organization ORS (WHO-ORS) has resulted in decreased mortality associated with acute diarrheal illnesses in children, although in general stool volume and diarrhea durations are not reduced. Decreased morbidity and mortality have occurred because of improved hydration status. Decreased morbidity has also been described in adults who used this therapy. Various modifications to the standard ORS have been derived. These modifications have included hypo-osmolar or hyperosmolar solutions, use of rice-based ORS, zinc supplementation, and the use of amino acids, including glycine, alanine, and glutamine. Some of these variations have been successful, some have not, and others are still under investigation. ORS has been used for travelers' diarrhea and to decrease intravenous (IV) fluid requirements in patients with short bowel syndrome (SBS) who require parenteral nutrition (PN). This paper reviews the standard WHO-ORS and its mechanism of action, followed by more contemporary reduced osmolarity ORS and rice-based ORS in non-cholera diarrhea. Various modifications to improve ORS are also discussed.

Why has oral rehydration for calves and children diverged: direct vs. indirect criteria of efficacy

Oral rehydration therapy (ORT) for acute diarrhoea has advanced in contrary directions in humans and animals; the unresolved question is whether this reflects species differences or a divergence in scientific outlook. This review suggests that the explanation lies in the fact that developments in veterinary ORT have the advantage of utilising more reliable criteria than those available from human patients. The dilemma for human ORT is that the validity of systematic reviews and meta-analyses are undermined when the underlying data only reflect crucial variables indirectly and unreliably. It is therefore possible that the approaches currently used to treat calves, which are radically different from those used by paediatricians, could potentially benefit children and the necessary additional research should be initiated. At a time when the value of animal models of human disease is frequently questioned, the benefits of being able to utilise disease models in the target species for clinical research deserve to be emphasised.

Effect of reducing sodium or glucose concentration in a hypo-osmolar ORS (oral rehydration salts) on absorption efficiency: marker perfusion study in rat jejunum

We evaluated the relative absorption efficiency of reducing the sodium or glucose concentration to make an ORS hypo-osmolar in a perfusion model. In nine adult albino rats 30 cm of jejunum was perfused at 0.4 ml/min with three glucose salt solutions for 45 min each, one with 60 mM sodium, 111 mM glucose, and osmolarity 247, one with 90 mM sodium, 60 mM glucose, and osmolarity 250, and one with 90 mM sodium, (111 mM) glucose, and osmolarity 301 (control solution). Each contained 2 g/L polyethylene glycol 4000 as a marker. The net water and sodium absorption were 2.8 (P < 0.001) and 2.6 (P < 0.001) times higher from low-sodium and 1.7 (P < 0.001)- and 1.5 (P < 0.001)-fold higher from low-glucose solutions compared to the control. Net glucose absorption was 2.2 (P < 0.001)-fold higher from low-sodium solutions compared to the control. The net water, sodium, potassium, and glucose absorptions were 1.6 (P < 0.001)-, 1.7 (P < 0.001)-, 1.36 (P < 0.05)-, and 4.15 (P < 0.001)-fold higher from low-sodium compared to low-glucose solutions. The hypo-osmolar ORS with reduced sodium was substantially more absorption efficient compared to the one with reduced glucose.

Efficacy and safety of a modified oral rehydration solution (ReSoMaL) in the treatment of severely malnourished children with watery diarrhea

OBJECTIVES

Efficacy, development of overhydration, and correction of electrolyte disturbances of severely malnourished children with acute diarrhea using a modified oral rehydration solution for malnourished children (termed ReSoMaL and recommended by the World Health Organization [WHO]) were evaluated and compared with standard WHO-oral rehydration solution (ORS).

STUDY DESIGN

Children age 6 to 36 months with severe malnutrition and acute watery diarrhea were randomized to ReSoMaL (n=65) or standard WHO-ORS (n=65). Major outcome measures included the number of children who developed overhydration and the number who corrected hypokalemia.

RESULTS

The numbers of children who developed overhydration were not significantly different (ReSoMaL vs WHO-ORS, 5% vs 12%, P=.2). ReSoMaL corrected basal hypokalemia in a greater proportion of children by 24 hours (36% vs 5%, P=.0006) and 48 hours (46% vs 16%, P=.004) compared with WHO-ORS. More children on ReSoMaL than WHO-ORS remained hyponatremic at 48 hours (29% vs 10%, P=.017). Three children in the ReSoMaL group developed severe hyponatremia by 24 hours, with one experiencing hyponatremic convulsions (serum sodium, 108 mmol/L).

CONCLUSIONS

ReSoMaL has a large beneficial effect on potassium status compared with standard ORS. However, ReSoMaL therapy may result in symptomatic hyponatremia and seizures in patients with severe diarrhea.

Fluid and electrolyte transport in the small intestine

The small intestine is in a dynamic state of secretion and absorption, the sum of which results in net absorption. Secretion is principally the result of chloride and bicarbonate extrusion through apical chloride channels after the activation of the second messengers cAMP, cGMP, and calcium. In addition to the cystic fibrosis transmembrane conductance regulator, several other candidate chloride channels have been identified and proposed to play a role in intestinal secretion, including the calcium-dependent chloride channel hCLCA1. Pathways leading to the negative control of secretion have been described that use cellular messengers, including inositol (3,4,5,6) tetrakisphosphate and phosphatidylinositol 3-kinase, which may act via basolateral potassium channels. The control of ion transport can also be viewed in terms of the enteric nervous system. The reflex neural pathways involved in enterotoxin-induced secretion have been substantiated and shown to involve 5-hydroxytryptamine, substance P, and the neurokinin 1 and 2 receptors in the sensory arm, and vasoactive intestinal peptide in the secretomotor efferents. Absorption of glucose in addition to active cotransport with sodium via the Na/glucose cotransporter protein has also been shown to occur passively through a carrier-mediated mechanism, using the membrane protein glucose transporter protein 2.

Reduced osmolarity oral rehydration solution for treating dehydration due to diarrhoea in children: systematic review

OBJECTIVES

To compare reduced osmolarity oral rehydration solution with standard World Health Organization oral rehydration solution in children with acute diarrhoea.

DESIGN

Systematic review of randomised controlled trials.

STUDIES

15 randomised controlled trials including 2397 randomised patients.

OUTCOMES

The primary outcome was unscheduled intravenous infusion; secondary outcomes were stool output, vomiting, and hyponatraemia.

RESULTS

In a meta-analysis of nine trials for the primary outcome, reduced osmolarity rehydration solution was associated with fewer unscheduled intravenous infusions compared with standard WHO rehydration solution (odds ratio 0.61, 95% confidence interval 0.47 to 0.81). Three trials reported that no patients required unscheduled intravenous infusion. Trials reporting secondary outcomes suggested that in the reduced osmolarity rehydration solution group, stool output was lower (standardised mean difference in the log scale -0.214 (95% confidence interval -0.305 to -0.123; 13 trials) and vomiting was less frequent (odds ratio 0.71, 0.55 to 0.92; six trials). Six trials sought presence of hyponatraemia, with events in three studies, but no significant difference between the two arms.

CONCLUSION

In children admitted to hospital with dehydration associated with diarrhoea, reduced osmolarity rehydration solution is associated with reduced need for unscheduled intravenous infusions, lower stool volume, and less vomiting compared with standard WHO rehydration solution.

Multicenter, randomized, double-blind clinical trial to evaluate the efficacy and safety of a reduced osmolarity oral rehydration salts solution in children with acute watery diarrhea

OBJECTIVE

To compare the efficacy of a reduced osmolarity oral rehydration salts (ORS) solution (75 mmol/L of sodium [Na], 20 mmol/L of potassium [K], 65 mmol/L of chloride, 10 mmol/L of citrate, and 75 mmol/L of glucose; osmolarity, 245 mosm/L) with that of the standard World Health Organization (WHO) ORS solution.

DESIGN

A multicenter, double-blind, randomized, controlled clinical trial conducted in children with acute diarrhea in 5 developing countries to measure mean stool output in the 24 hours after randomization, proportion of children who required unscheduled intravenous therapy, proportion of children who vomited in the first 24 hours, and diarrhea duration after randomization.

RESULTS

A total of 675 children who ranged in age from 1 to 24 months and who had acute diarrhea and dehydration were enrolled in the trial; 341 were randomized to receive reduced osmolarity ORS solution, and 334 were randomized to receive the WHO ORS solution. The mean (SE) stool output (g/kg) in the first 24 hours (reduced osmolarity ORS solution vs WHO ORS solution = 114 [4] vs 125 [5]) and during the total study period (reduced osmolarity ORS solution vs WHO ORS solution = 320 [18] vs 331 [18]) were comparable. The proportion of children who vomited in the first 24 hours (reduced osmolarity ORS solution vs WHO ORS solution = 58% vs 62%) and the diarrhea duration in the 2 treatment groups, compared by log rank test, were similar. The proportion of children who required unscheduled intravenous therapy was significantly lower in children who received reduced osmolarity ORS solution (10%) as compared with those who received the WHO ORS solution (15%; odds ratio = 0.6, 95% confidence interval = 0.4-1.0). There was no significant difference in the incidence of hyponatremia (serum Na <130 mmol/L) at 24 hours between the 2 treatment groups (11% in reduced osmolarity ORS solution group vs 9% in the WHO ORS solution group; odds ratio = 1.3; 95% confidence interval = 0.8-2.2). The frequency of patients with serum Na <125 mmol/L at 24 hours was 13 of 341 (4%) in children who were treated with reduced osmolarity ORS solution versus 7 of 334 (2%) in children who received the WHO ORS solution.

CONCLUSIONS

Treatment with reduced osmolarity ORS solution was associated with a 33% reduction in the need for unscheduled intravenous therapy and had no apparent effect on stool output and illness duration when compared with treatment with the standard WHO ORS solution. Children with acute diarrhea, therefore, may benefit from a reduced osmolarity ORS solution. The results of trials that examine the efficacy and safety of reduced osmolarity ORS solution in adult patients with cholera have to be taken into consideration before consensus on composition of oral rehydration formulation can be reached.

Reduced osmolarity oral rehydration solution for persistent diarrhea in infants: a randomized controlled clinical trial

OBJECTIVE

We evaluated and compared the efficacy of the World Health Organization (WHO) oral rehydration solution (ORS) and 2 different formulations of reduced osmolarity ORSs in infants with persistent diarrhea.

STUDY DESIGN

Infants with persistent diarrhea (n = 95) were randomized to 1 of the 3 ORSs: WHO-ORS (control, n = 32), a glucose-based reduced osmolarity ORS (RORS-G, n = 30), or a rice-based reduced osmolarity ORS (RORS-R, n = 31) for replacement of ongoing stool losses for up to 7 days. Major outcome measures were stool volume and frequency, ORS intake, and resolution of diarrhea.

RESULTS

Although there were variations from one study day to another, the stool volume was approximately 40% less in the reduced osmolarity ORS groups; consequently, these children required less ORS (22% for RORS-G and 27% for RORS-R groups). A higher proportion of children in the RORS-R groups also had resolution of diarrhea during the study period. No children in any of the treatment groups had hyponatremia.

CONCLUSION

Reduced osmolarity ORS is clinically more effective than WHO-ORS and may thus be advantageous for use in the treatment of children with persistent diarrhea.

Double blind, randomised controlled clinical trial of hypo-osmolar oral rehydration salt solution in dehydrating acute diarrhoea in severely malnourished (marasmic) children

AIMS

To compare the clinical efficacy of hypo-osmolar oral rehydration salt (ORS) solution (224 mmol/l) and standard ORS solution (311 mmol/l) in severely malnourished (marasmic) children having less than 60% Harvard standard weight for age with dehydrating acute watery diarrhoea.

METHODS

In a double blind, randomised, controlled trial, 64 children aged 6-48 months were randomly assigned standard (n = 32) or hypo-osmolar ORS (n = 32).

RESULTS

Stool output (52.3 v 96.6 g/kg/day), duration of diarrhoea (41.5 v 66.4 hours), intake of ORS (111.5 v 168.9 ml/kg/day), and fluid intake (214.6 v 278.3 ml/kg/day) were significantly less in the hypo-osmolar group than in the standard ORS group. Percentage of weight gain on recovery in the hypo-osmolar group was also significantly less (4.3 v 5.4% of admission weight) than in the standard ORS group. A total of 29 (91%) children in the standard ORS group and 32 (100%) children in the hypo-osmolar group recovered within five days of initiation of therapy. Mean serum sodium and potassium concentrations on recovery were within the normal range in both groups.

CONCLUSION

Our findings suggest that hypo-osmolar ORS has beneficial effects on the clinical course of dehydrating acute watery diarrhoea in severely malnourished (marasmic) children. Furthermore, children did not become hyponatraemic after receiving hypo-osmolar ORS.

Reduced osmolarity oral rehydration solution for treating dehydration caused by acute diarrhoea in children

BACKGROUND

Oral rehydration solution (ORS) has reduced childhood deaths from diarrhoea in many countries. Recent studies suggest that the currently recommended formulation of ORS recommended by the World Health Organization (WHO) may not be optimal, and solutions that contain lower concentrations of sodium and glucose may be more effective.

OBJECTIVES

In children with acute diarrhoea, to compare reduced osmolarity glucose-based oral rehydration salt solution with international WHO formulation.

SEARCH STRATEGY

The Cochrane Collaboration Trials Register, MEDLINE, and EMBASE were searched. Additional trials were identified by hand searching. Content experts were contacted.

SELECTION CRITERIA

Randomised controlled trials comparing reduced osmolarity ORS solution with the WHO formulation. Outcomes sought were unscheduled intravenous fluid infusion therapy and measures of clinical illness.

DATA COLLECTION AND ANALYSIS

Data were extracted by two reviewers. We tested for heterogeneity using the chi-square statistic, conducted sensitivity analysis by allocation concealment, and the regression approach to assess funnel plot asymmetry from selective trial publication.

MAIN RESULTS

The primary outcome was reported in 12 trials. In a meta-analysis of nine trials, reduced osmolarity ORS was associated with fewer unscheduled infusions compared with standard WHO ORS (Mantel Haenzel odds ratio 0.61, 95% confidence interval 0.47 to 0.81) with no evidence for heterogeneity between trials. No unscheduled intravenous fluid infusion therapy was required in any participant in three trials. Thirteen trials reported stool output, and data suggested less stool output in the reduced osmolarity ORS group. Vomiting was less frequent in the reduced osmolarity group in the six trials reporting this. Six trials sought hyponatraemia, with events in three studies, but no obvious difference between the two arms.

REVIEWER'S CONCLUSIONS

In children admitted to hospital with diarrhoea, reduced osmolarity ORS when compared to WHO ORS is associated with fewer unscheduled intravenous infusions, smaller stool volume post randomisation, and less vomiting. No additional risk of developing hyponatraemia when compared with WHO ORS was detected.

Partially hydrolyzed guar gum-supplemented oral rehydration solution in the treatment of acute diarrhea in children

BACKGROUND

Partially hydrolyzed guar gum (Benefiber; Novartis Nutrition, Minneapolis, MN, U.S.A.) is fermented by colonic bacteria liberating short-chain fatty acids (SCFAs), which accelerate colonic absorption of salt and water. The purpose of this study was to evaluate the effect of Benefiber (BF)-supplemented World Health Organization Oral Rehydration Solution (WHO ORS) in the treatment of acute noncholera diarrhea in children.

METHODS

A double-blind, randomized, controlled clinical trial was performed at ICDDR,B in 150 male children aged 4 to 18 months who had watery diarrhea of less than 48 hours' duration. After admission, children were assigned to receive either WHO ORS or BF-supplemented WHO ORS until recovery. Major outcome measures, such as duration of diarrhea and amount of stool output, were compared between the treatment groups.

RESULTS

Patients receiving BF-supplemented WHO ORS had significantly reduced duration of diarrhea compared with the control group (mean +/- SD, 74 +/- 37 vs. 90 +/- 50 hours, P = 0.03). Survival analysis for duration of diarrhea also showed a reduction the BF-supplemented WHO ORS-treated group (P = 0.025, log rank test). There was also less stool output daily from days 2 through 7 in the patients treated with BF-supplemented WHO ORS compared with that in the children treated with WHO ORS; the reduction was significant on day 7 only.

CONCLUSION

Benefiber added to standard WHO ORS substantially reduces the duration of diarrhea and modestly reduced stool output in acute noncholera diarrhea in young children, indicating its potential as a new antidiarrheal therapy for acute diarrhea in children.

Efficacy and safety of oral rehydration solution with reduced osmolarity in adults with cholera: a randomised double-blind clinical trial. CHOICE study group

BACKGROUND

The effects of oral rehydration solution (ORS) with reduced osmolarity on children with acute watery diarrhoea are known, but little is known about the effects of such ORS on adults with cholera. We aimed to compare the efficacy and safety of an ORS with reduced osmolarity with that of standard WHO ORS in adults with cholera.

METHODS

We undertook a double-blind, controlled clinical trial in adults with severe cholera at the International Centre for Diarrhoeal Disease Research, Bangladesh. Our primary outcomes were mean stool output in the 24 h after randomisation, proportion of patients who needed unscheduled intravenous therapy, and proportion of patients with biochemical hyponatraemia 24 h after randomisation.

FINDINGS

147 patients received ORS with reduced osmolarity and 153 received standard WHO ORS. There was no significant difference between the two groups in terms of main outcome variables: mean initial 24 h and total stool output (reduced osmolarity vs standard WHO ORS 212 [SE 8] vs 207 [8] and 284 [13] vs 273 [13] g/kg respectively), duration of diarrhoea (46 [1.5] vs 43 [1.5]). The proportion of patients vomiting during the first 24 h and the proportion who received unscheduled intravenous infusion during the first 24 h was similar between groups. More patients on reduced osmolarity ORS than on standard WHO ORS developed hyponatraemia during the first 24 h, defined as serum sodium concentration below 130 mmol/L (29 of 142 vs 16 of 150; odds ratio 2.1 [95% CI 1.1-4.1]). However, all hyponatraemic patients in both groups were symptom-free and the proportion of patients with serum sodium concentration below 125 mmol/L was similar between groups.

INTERPRETATION

There was no difference in clinical outcome between cholera patients treated with reduced osmolarity ORS solution and those treated with standard WHO ORS. The risk of increased incidence of symptom-free hyponatraemia in patients with cholera treated with an ORS with reduced osmolarity should be further assessed by meta-analysis. The risk should be taken into account when choice of ORS is made in areas in which cholera is endemic.

Successful treatment of rotavirus diarrhea in children with immunoglobulin from immunized bovine colostrum

BACKGROUND

Oral ingestion of immunoglobulins in humans has been shown to be effective as prophylaxis against enteric infections. However, its therapeutic effect in children with infectious diarrhea has hitherto not been proven. We treated children with rotavirus diarrhea with immunoglobulins extracted from immunized bovine colostrum (IIBC) containing high titers of antibodies against four rotavirus serotypes.

METHODS

In this double blind placebo-controlled trial, 80 children with rotavirus diarrhea were randomly assigned to receive orally either 10 g of IIBC (containing 3.6 g of antirotavirus antibodies) daily for 4 days or the same amount of a placebo preparation. The daily stool output (grams/kg/day), intake of oral rehydration solution (ml/kg/day), stool frequency (number of stools/day) and presence of rotavirus in stool were monitored for the 4 days during treatment.

RESULTS

Children who received IIBC had significantly less daily and total stool output and stool frequency and required a smaller amount of oral rehydration solution than did children who received placebo (P < 0.05). Clearance of rotavirus from the stool was also earlier in the IIBC group compared with the placebo group (mean day, 1.5 vs. 2.9, P < 0.001). No adverse reactions from the colostrum treatment were observed.

CONCLUSIONS

Treatment with antirotavirus immunoglobulin of bovine colostral origin is effective in the management of children with acute rotavirus diarrhea.

Management of acute diarrhoea with low osmolarity oral rehydration solutions and Lactobacillus strain GG

Two hypotonic oral rehydration solutions with osmolarities of 224 mosmol/l (Na+ 60 mmol/l, glucose 84 mmol/l) and 204 mosmol/l (Na+ 60 mmol/l, glucose 64 mmol/l), respectively, and oral treatment with Lactobacillus GG were evaluated in a double blind trial in children aged 6-36 months hospitalised for acute diarrhoea. Early administration of Lactobacillus GG at the start of oral rehydration resulted in the shortest duration of diarrhoea, best weight gain, and fastest correction of acidosis. A reduced osmolarity oral rehydration solution (224 mosmol/l) combined with early administration of Lactobacillus GG is an effective treatment for acute diarrhoea in young children; further reduction of osmolarity may not be beneficial.

A trial in the Karelian Republic of oral rehydration and Lactobacillus GG for treatment of acute diarrhoea

In a controlled trial in Petrozavodsk, Karelia, the effects of oral rehydration and Lactobacillus strain GG (LGG) on recovery from acute diarrhoea (27% rotavirus, 21% bacterial aetiology) were studied in 123 children aged between 1 and 36 months of age. On admission to hospital, the patients were first randomized to receive either isotonic oral rehydration solution (ORS) with osmolarity 311 mosmol/l and sodium 90 mmol/l (WHO-ORS), or a hypotonic ORS with osmolarity 224 mosmol/l and sodium 60 mmol/l (Light-ORS), and thereafter randomized to receive either 5 x 10(9) colony forming units of LGG or a matching placebo. The two ORS performed equally for acute rehydration, and oral rehydration with either ORS was associated with a shorter duration of diarrhoea than intravenous rehydration (p = 0.036). Patients receiving LGG had a significantly shorter duration of watery diarrhoea [mean (SD) 2.7 (2.2) days] than those receiving the placebo [3.7 (2.8) days, p = 0.03]. LGG significantly shortened the duration of rotavirus diarrhoea but not diarrhoea with confirmed bacterial aetiology.

Randomised double blind study of hypotonic oral rehydration solution in diarrhoea

A hypotonic (osmolality 224 mmol/l, sodium 60 mmol/l) oral rehydration solution (ORS) was compared with an isotonic high glucose ORS (osmolality 304 mmol/l, sodium 60 mmol/l) in children with acute diarrhoea in a randomised double blind study. The stool output and hence the mean consumption of ORS for maintenance hydration was less (p = 0.036) in patients receiving hypotonic (69 ml/kg) than isotonic (97 ml/kg) ORS. Hypotonic ORS was more effective in patients with rotavirus positive than with rotavirus negative diarrhoea.

Hypo-osmolar sucrose oral rehydration solutions in acute diarrhoea: a pilot study

Based on studies showing improved absorption of hypo-osmolar oral rehydration solutions (ORS) with reduced glucose and sodium concentration, a hypo-osmolar ORS with sucrose replacing glucose (sodium 60, potassium 15, chloride 60, citrate 5, sucrose 58 mmol l-1, calculated osmolality 198 mOsm kg-1) was compared with mildly hyperosmolar glucose ORS (WHO) in 46 children aged 6-30 months with acute diarrhoea and dehydration. In the hypo-osmolar sucrose ORS group (n = 18) faecal output was less by 30% during the initial 24 and 48 h compared with controls, suggesting better absorption. Sucrose may be a suitable alternative to glucose in an absorption-efficient hypo-osmolar ORS.

Reduced osmolarity oral rehydration salt in Cholera

In a controlled clinical trial conducted in 34 adults with severe cholera diarrhoea, the use of a relatively dilute oral rehydration salt (ORS) solution (sodium 67, potassium 20, chloride 66, citrate 7, glucose 89 mmol/l, osmolality 249 mOsmol/kg) caused a 29% (p=0.003) reduction in stool output over the first 24 h and a 37% (p=0.001) reduction over the first 48 h compared with 29 controls who received the hyperosmolar WHO/UNICEF ORS. No controls but 3 study-group patients had marked but asymptomatic hyponatraemia (sodium <125 mmol/l) at 24 h. Twenty-four % of controls and 12% of patients receiving the dilute ORS needed unscheduled intravenous therapy for recurrence of dehydration. The ORS intake was twice the 48 h stool volume in controls and 3 times in the study group. The test ORS with a reduced glucose and sodium concentration is more efficient than the WHO/UNICEF ORS in preserving net intestinal fluid balance in severe cholera.