Magic bullet: the history of oral rehydration therapy

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Review on development and community implementation of oral rehydration therapy

The review of the current status and implementation of Oral Rehydration Therapy at the community level have been presented in this communication with special emphasis on its development, ORS access rate, ORS use rate and home available fluids. The global ORS supply has gone up an increased eleven folds since 1981. Similarly the ORS access rate has also increase from 46% to 68% in 1991. However, the global ORS use rate was low (21%). The major constraints during ORT implementation which have been reported by several scientists are also discussed.

Thermal effects of prolonged treadmill exercise in the heat. 1974

Six trained men 21-38 yrs old ran 19-29 km (1.5 to 2.5 hrs) approximately 75% of their VO2 max on a level treadmill in the heat (33.5/21.5 degrees C db/wb, wind velocity 36 m/min). Every 20 min while running they (a) drank 200 ml of 10 degrees C water, (b) drank 200 ml of water at core body temperature, or (c) sponged their faces, arms, and trunks for 2 min with a towel soaked in 10 degrees C water. In another series of experiments each subject (d) hydrated 30 min before the run by drinking 1 liter of water, (e) hydrated and performed (a) above, and (f) hydrated and performed (b) above. Rectal temperature (Tre) and body weight loss (WL) were determined every 30 min and metabolism at 45 min of running. Terminal Tre after (a) through (f) averaged 39.1, 39.3, 39.9, 39.7, 39.1, and 39.3 degrees C respectively. During a control run the corresponding mean Tre was 39.9 degrees C. In a 66.7 kg man with a body weight/surface area (BW/SA) ratio of 37.5 and running at 74% of his VO2 max, Tre rose 0.4 degrees C/1% WL with increasing WL's greater than 2.0% of his initial body weight regardless of the intervention imposed. In another subject weighing 70 kg with a BW/SA ratio of 38.8 and running at 83% of his VO2 max, Tre rose 0.49 degrees C/1% WL over the entire range of WL's.(ABSTRACT TRUNCATED AT 250 WORDS)

[The history of the first "voluntary" oral hydration center in Mexico (1959)]

There are some historic facts about the "First Center for Voluntary Oral Rehydration" begun 1959 at Hospital Infantil de México (Children's Hospital) was clearly demonstrated useful, 508 infants with diarrhea were treated. 90.94% were cured and dehydration corrected. Antibiotics were not much useful. Oral rehydration is considered the method of choice to begin treatment of the patient with gastroenteritis.

The treatment of cholera: clinical science at the bedside

In 1959-1961, two major international centers for the study of cholera were established in Calcutta and in Dacca, Bangladesh. As the result of collaborative work in these centers, a simple effective oral therapy for cholera, using ingredients available in virtually every part of the world, was defined. Through the well-coordinated efforts of the World Health Organization (WHO), knowledge of how to prepare and administer oral rehydration therapy has now been disseminated throughout most of the world. With this background, when Peru was attacked in 1991 by a massive and totally unanticipated outbreak of cholera, a remarkably well-organized national response to the epidemic achieved a survival rate greater than 99% in greater than 300,000 cholera patients during the first year of the epidemic. Thus the results of clinical research on the Indian subcontinent, widely disseminated through educational programs by the WHO, have resulted in unparalleled success in the treatment of the largest epidemic outbreak of cholera in the 20th century.

[Development of a rehydration therapy in diarrheic disease. 1980]

Intravenous rehydration is required only in patients with severe diarrhea due to V. cholerae who are in shock, with absent peripheral pulse and blood pressure; when the shock has been corrected, rehydration can be completed using an oral rehydration solution. The intravenous solution to be used is 5:4: 1 (5g of sodium chloride, 4g of sodium bicarbonate and 1g of potassium chloride per liter) or a comparable commercial alkaline solution. For oral rehydration a solution is used containing 3.5 g sodium chloride, 2.5g sodium bicarbonate, 1.5g potassium chloride and 20g of glucose (or 40g of sucrose) per liter. These fluids are administered in a volume replacing the amount lost before treatment was initiated and the fluids lost in the continuing diarrhea. With this management, a case fatality rate of 50% in the untreated falls to less than 1%. The addition of antibiotics such as tetracycline and furazolidone reduces the duration of diarrhea and the need for continuing fluid balance observation. Intravenous rehydration of severe diarrhea cases with normal saline solution or with 5% glucose solution increases the acidosis with resulting veno-constriction, which favors the pooling of blood in the heart and the pulmonary circulation leading to cardiac overload and then failure and circulatory peripheral collapse. When acidosis is corrected by the sodium bicarbonate solution and with adequate fluid replacement, normal hemodynamics are reestablished and the patient immediately recovers from the collapse. In cases of mild or moderate diarrhea, replacement entirely by oral rehydration of the estimated volume of lost fluid alone is usually sufficient. This management of diarrhea is applicable for diarrhea from any cause, including enterotoxigenic Escherichia coli, Rotavirus, Salmonella and Shigella as well as Vibrio cholerae.

History and rationale of oral rehydration and recent developments in formulating an optimal solution

Oral rehydration therapy with glucose-electrolyte solutions has been one of the major therapeutic advances of the century. This alarmingly simple intervention developed from a basic scientific observation in the laboratory, when it was shown that sodium and glucose transport in the small intestine are coupled and thus the presence of glucose in an electrolyte solution promotes absorption of both sodium ions and water. Even more important, sodium/glucose co-transport continues despite the secretory diarrhoea of cholera and enterotoxigenic E. coli and after intestinal damage due to rotavirus. Despite widespread use of the oral rehydration solutions (ORS) recommended by the World Health Organization (WHO), controversy continues about the optimal composition of these solutions. Discussion centres around the sodium and glucose concentrations, the osmolality and whether base (bicarbonate) or base-precursor (citrate) is necessary. Already there is a clear divide between the developing world, where the WHO solution (Na 90, glucose 111 and bicarbonate 30 mmol/L) is widely used, and the industrialised world, where solutions with lower sodium and until recently higher glucose concentrations have been favoured. Recently, attempts have been made to optimise ORS using animal and human model systems before submitting new candidate ORS to clinical trial. Results to date suggest that hypotonic ORS containing 50-60 mmol/L sodium and 90-100 mmol/L glucose produce maximal water absorption. The presence of base or base-precursor appears to offer little with regard to the promotion of sodium and water absorption and its role in combating acidosis remains controversial. Complex substrates such as rice powder and glucose polymers may eventually replace glucose in ORS, since their addition reduces ORS osmolality still further.