- Email: [email protected]
Oral rehydration for diarrhea
Volume 101 Number 4
When an environmental agent is suspected as the cause for a cluster of disease, local experts and authorities should usually be consulted first. If they need assistance they can and should call on the Centers for Disease Control. The Environmental Protection Agency is responsible for identifying chemicals in environmental emergencies, a key resource for which is the NIH-EPA Chemical Information System. 4 This system contains extensive data on more than 200,000 chemicals. The fear of effects from environmental pollution was referred to as "secondary poisoning"; that is, symptoms caused by anxiety generated by publicity about the event. This was an enormous problem in Michigan with regard to PBBs, at Three Mile Island, and in Hiroshima and Nagasaki. Some participants suggested that the problem might be diminished by not withholding information, but others cautioned that giving premature information may erroneously imply liability. HEALTH POLICY, CHILDREN, AND PEDIATRICIANS Children were a main determinant in preparing several recent health regulations. For example, the EPA argued that in exposures to airborne lead, children were the most susceptible and had to be protected. In consequence, 99.5%
Chemical a n d radiation h a z a r d s
497
of the population would be protected if the new standard were achievable. Are pediatricians represented often enough on the inner councils of government in relation to health? Yes, for problems or agencies that primarily concern children, but not when the general population is exposed to newly recognized environmental agents, such as PBBs or chemical dumps. To increase participation by pediatricians, it was suggested that professional societies be persistent in recommending extremely able people. As another participant put it, "That's what doctors have to be, I think, both scientists and social advocates."
REFERENCES 1. Committee on Environmental Hazards, American Academy of Pediatrics: Conference on the Pediatric Significance of Peacetime Radioactive Fallout, Pediatrics 41:165, 1968. 2. Committee on Environmental Hazards, American Academy of Pediatrics: The susceptibility of the fetus and child to chemical pollutants, Pediatrics 53:775, 1974. 3. Bloom AD, editor: Guidelines for studies of human exposed populations to mutagenic and reproductive hazards. White Plains, N. Y., 1981, March of Dimes Birth Defects Foundation. 4. Milne GWA, Fisk CL, Heller SR, and Potenzone R Jr: Environmental uses of the NIH-EPA chemical information system, Science 215:371, 1982.
Oral rehydration for diarrhea Laurence Finberg, M.D.,* Brooklyn, N. Y., Paul A. Harper, M.D., Harold E. Harrison, M.D., and R. Bradley Sack, M.D., Baltimore, Md.
From the State University o f New York, Downstate Medical Center; the Departments o f Maternal and Child Health and Population Dynamics, Johns Hopkins School o f Hygiene; and the Departments o f Pediatrics and Medicine, Division o f Geographic Medicine, Johns Hopkins School o f Medicine. *Reprint address: Department of Pediatrics. SUNY, Downstate Medical Center, 450 Clarkson Ave., Box 49, Brooklyn, NY 11203.
0022-3476/82/100497+03500.30/0 9 1982 The C. V. Mosby Co.
FROM MARCH 15 to 17, 1982, an international group of 35 pediatricians, epidemiologists, and public health workers, all with interest and extensive experience in the Abbreviations used WHO: WorldHealth Organization ORS: oral rehydrating solution
4 98
Finberg et al.
management of infantile diarrheal disease in the United States and in developing countries, met in Baltimore to review the concepts and status with respect to oral rebydration, oral fluid balance maintenance, and nutritional therapy. Papers were presented and discussed for a 21/2-day period covering historic aspects and the dangers of altered sodium, potassium, and acid-base status and of lactose intolerance and refeeding techniques after acute diarrhea. The meeting was held under the auspices of the Division of Geographic Medicine and the Departments of Maternal and Child Health and Population Dynamics of the Johns Hopkins University. The agenda for the meeting included a discussion of the appropriate composition and the methods of usage of oral electrolyte-glucose solution for rehydration, maintenance of hydration during enteritis, and prevention of dehydration. Second, feeding advice during acute and subacute enteritis was reviewed, and finally, there was discussion of the techniques of designing programs for developing countries. What follows here is a summary statement of agreements about the first two of these topics, which have been the focus of controversy for many years and which are of interest to both our domestic and international readers. The statement was drafted and then modified for publication after whole-group consensus was reached by the signatories, who also had served as the arrangers of the conference. The first portion of the meeting was devoted to an historic review of the use of oral electrolyte-carbohydrate solutions for diarrheal disease. Shortly after D. C. Darrow had demonstrated the importance of potassium in the parenteral repair of dehydration subsequent to enteritis, he and H. E. Harrison began using an oral solution of sodium and potassium salts of chloride and base plus glucose (1946). The solution was used either after parenteral repair for maintenance of hydration (ongoing insensible water losses plus variable continuing losses in stool) or to prevent dehydration in infants at the outset of enteritis. The carbohydrate content (3.3%) of these early solutions was set to minimize protein breakdown and to prevent ketosis in the infants. Later, commercial development by United States companies raised the carbohydrate content to 5 or 8%, sometimes as glucose and sometimes as mixtures of carbohydrates. Subsequently, workers (R. A. Philips and associates) began to use oral electrolyte-glucose solutions to repair dehydration and to maintain hydration in adults with cholera, in whom the stool losses of water and sodium chloride are enormous. They demonstrated in vivo that an important mechanism of sodium transport in the intestine couples the ion with active glucose absorption. The glucose concentration (2%, or 111 mmol/L) was then set to
The Journal of Pediatrics October 1982
promote maximum uptake of sodium and to avoid the osmotic influence of any unabsorbed glucose. The high sodium concentration (90 mmol/L) used in the solutions for therapy of cholera, even after adjustment for children, posed a threat of hypernatremia in infants if used alone (i.e., without additional water) in noncholera enteritides for either maintenance or prevention. The danger occurs because of the much lower sodium concentration in such stools and because of the high insensible daily water losses in infants. The assembled group then agreed that the following guidelines would be appropriate for the use of oral electrolyte-glucose solution, both in developing countries and in the United States: 1. The World Health Organization solution (oral rehydrating solution) containing 90 mmol/L sodium, 20 mmotfL potassium, plus base and glucose at 111 mmolfL (2%) is a suitable oral rehydrating solution for infantile dehydration with hypovolemia regardless of the cause of the dehydration or the nature of the physiologic disturbance (serum sodium concentration). The volume to be administered should be judged clinically to replace the estimated deficit. 2. Maintenance of hydration (or prevention of dehydration) during diarrhea may appropriately utilize the W H O ORS by giving additional free water to the infants. This may be by ad libitum breast-feedings, by one part plain (or flavored) water for two parts ORS, or by juices, preferably those containing potassium. When plain water is used, potassium-containing foods should be offered as soon as possible. 3. Alternatively, in those regions such as the United States or wherever economically and logistically feasible, a separate maintenance and prevention solution may be used. This solution should differ from many present commercial oral electrolyte solutions by having: a lower glucose or other suitable carbohydrate concentration, e.g., 111 mmol/L of glucose; a higher sodium concentration, e.g., 50 to 60 mmol/L; a potassium concentration of 20 to 30 mmol/L; and anions as chloride (30 to 50 mmol/L) and base (e.g., bicarbonate or citrate, 30 mmol/L). Such a solution is well suited for replacement of stool losses in infantile enteritis from viral and bacterial causes. At the same time, there is adequate free water to allow excretion of what will sometimes be an excess of electrolyte. As an additional precaution, when prescribing such a solution for prevention, the daily volume should be limited (usually 150 ml/kg/day) and the caretaker instructed to administer any additional fluid as plain water or human milk to satisfy thirst. Acute diarrheal disease is known to contribute significantly to the development and progression of malnutrition
Volume 101 Number 4
in children. One of the goals of therapy is, therefore, to minimize these adverse effects through the promotion of optimal nutritional intake during and immediately following episodes of diarrhea. The use of the oral glucoseelectrolyte solutions aids in these endeavors through the rapid restoration of homeostasis which in turn makes it possible for the child to resume food intake as well. Glucose in the oral treatment solutions is not itself a significant source of calories, although its absorption, which remains relatively intact during a diarrheal episode, enables the coupled absorption of sodium and water to occur. Although temporary lactase deficiency is a wellrecognized feature of acute diarrheas of all causes, there is no suggestion that the continuation of breast-feeding during a diarrheal episode is harmful, and therefore, this practice is to be encouraged. On the other hand, for reasons not well known, cow milk and lactose-containing formulas may not be so well tolerated during and immediately following an acute diarrheal episode. Although no definitive data are available, it seems appropriate, in non-breast-fed infants with moderate to severe diarrhea, to avoid the use of lactose-containing milk or formulas for one or two days and then to resume milk feedings cautious-
Oral rehydration f o r diarrhea
499
ly. Cereals (rice, wheat noodles), bananas, potatoes, and other nonlaetose, carbohydrate-rich foods can be offered during this period after the initial few hours of rehydration with oral electrolyte solution. Unfortunately, the optimal dietary methods to use during this time are not yet well worked out. There is evidence, however, that many digestive and absorptive processes in the intestine are normal or near normal (monosaccharride, amino acids) during an episode of diarrhea, and it is therefore encouraging to think that satisfactory methods that make use of locally available foods will almost certainly be developed. Fasting beyond the initial rehydration period is not indicated (except under special circumstances) and, in children with borderline nutritional status, may be particularly detrimental. After the initial replacement of fluid and electrolyte losses, age-appropriate food should be provided as soon as it can be accepted by the child. Oral rehydration therapy is effective, safe, and inexpensive. Its extensive use should result in a decrease in the need for hospitalization, and in the reduction of the deleterious effects of acute diarrhea on nutrition and on the mortality rate.
When an environmental agent is suspected as the cause for a cluster of disease, local experts and authorities should usually be consulted first. If they need assistance they can and should call on the Centers for Disease Control. The Environmental Protection Agency is responsible for identifying chemicals in environmental emergencies, a key resource for which is the NIH-EPA Chemical Information System. 4 This system contains extensive data on more than 200,000 chemicals. The fear of effects from environmental pollution was referred to as "secondary poisoning"; that is, symptoms caused by anxiety generated by publicity about the event. This was an enormous problem in Michigan with regard to PBBs, at Three Mile Island, and in Hiroshima and Nagasaki. Some participants suggested that the problem might be diminished by not withholding information, but others cautioned that giving premature information may erroneously imply liability. HEALTH POLICY, CHILDREN, AND PEDIATRICIANS Children were a main determinant in preparing several recent health regulations. For example, the EPA argued that in exposures to airborne lead, children were the most susceptible and had to be protected. In consequence, 99.5%
Chemical a n d radiation h a z a r d s
497
of the population would be protected if the new standard were achievable. Are pediatricians represented often enough on the inner councils of government in relation to health? Yes, for problems or agencies that primarily concern children, but not when the general population is exposed to newly recognized environmental agents, such as PBBs or chemical dumps. To increase participation by pediatricians, it was suggested that professional societies be persistent in recommending extremely able people. As another participant put it, "That's what doctors have to be, I think, both scientists and social advocates."
REFERENCES 1. Committee on Environmental Hazards, American Academy of Pediatrics: Conference on the Pediatric Significance of Peacetime Radioactive Fallout, Pediatrics 41:165, 1968. 2. Committee on Environmental Hazards, American Academy of Pediatrics: The susceptibility of the fetus and child to chemical pollutants, Pediatrics 53:775, 1974. 3. Bloom AD, editor: Guidelines for studies of human exposed populations to mutagenic and reproductive hazards. White Plains, N. Y., 1981, March of Dimes Birth Defects Foundation. 4. Milne GWA, Fisk CL, Heller SR, and Potenzone R Jr: Environmental uses of the NIH-EPA chemical information system, Science 215:371, 1982.
Oral rehydration for diarrhea Laurence Finberg, M.D.,* Brooklyn, N. Y., Paul A. Harper, M.D., Harold E. Harrison, M.D., and R. Bradley Sack, M.D., Baltimore, Md.
From the State University o f New York, Downstate Medical Center; the Departments o f Maternal and Child Health and Population Dynamics, Johns Hopkins School o f Hygiene; and the Departments o f Pediatrics and Medicine, Division o f Geographic Medicine, Johns Hopkins School o f Medicine. *Reprint address: Department of Pediatrics. SUNY, Downstate Medical Center, 450 Clarkson Ave., Box 49, Brooklyn, NY 11203.
0022-3476/82/100497+03500.30/0 9 1982 The C. V. Mosby Co.
FROM MARCH 15 to 17, 1982, an international group of 35 pediatricians, epidemiologists, and public health workers, all with interest and extensive experience in the Abbreviations used WHO: WorldHealth Organization ORS: oral rehydrating solution
4 98
Finberg et al.
management of infantile diarrheal disease in the United States and in developing countries, met in Baltimore to review the concepts and status with respect to oral rebydration, oral fluid balance maintenance, and nutritional therapy. Papers were presented and discussed for a 21/2-day period covering historic aspects and the dangers of altered sodium, potassium, and acid-base status and of lactose intolerance and refeeding techniques after acute diarrhea. The meeting was held under the auspices of the Division of Geographic Medicine and the Departments of Maternal and Child Health and Population Dynamics of the Johns Hopkins University. The agenda for the meeting included a discussion of the appropriate composition and the methods of usage of oral electrolyte-glucose solution for rehydration, maintenance of hydration during enteritis, and prevention of dehydration. Second, feeding advice during acute and subacute enteritis was reviewed, and finally, there was discussion of the techniques of designing programs for developing countries. What follows here is a summary statement of agreements about the first two of these topics, which have been the focus of controversy for many years and which are of interest to both our domestic and international readers. The statement was drafted and then modified for publication after whole-group consensus was reached by the signatories, who also had served as the arrangers of the conference. The first portion of the meeting was devoted to an historic review of the use of oral electrolyte-carbohydrate solutions for diarrheal disease. Shortly after D. C. Darrow had demonstrated the importance of potassium in the parenteral repair of dehydration subsequent to enteritis, he and H. E. Harrison began using an oral solution of sodium and potassium salts of chloride and base plus glucose (1946). The solution was used either after parenteral repair for maintenance of hydration (ongoing insensible water losses plus variable continuing losses in stool) or to prevent dehydration in infants at the outset of enteritis. The carbohydrate content (3.3%) of these early solutions was set to minimize protein breakdown and to prevent ketosis in the infants. Later, commercial development by United States companies raised the carbohydrate content to 5 or 8%, sometimes as glucose and sometimes as mixtures of carbohydrates. Subsequently, workers (R. A. Philips and associates) began to use oral electrolyte-glucose solutions to repair dehydration and to maintain hydration in adults with cholera, in whom the stool losses of water and sodium chloride are enormous. They demonstrated in vivo that an important mechanism of sodium transport in the intestine couples the ion with active glucose absorption. The glucose concentration (2%, or 111 mmol/L) was then set to
The Journal of Pediatrics October 1982
promote maximum uptake of sodium and to avoid the osmotic influence of any unabsorbed glucose. The high sodium concentration (90 mmol/L) used in the solutions for therapy of cholera, even after adjustment for children, posed a threat of hypernatremia in infants if used alone (i.e., without additional water) in noncholera enteritides for either maintenance or prevention. The danger occurs because of the much lower sodium concentration in such stools and because of the high insensible daily water losses in infants. The assembled group then agreed that the following guidelines would be appropriate for the use of oral electrolyte-glucose solution, both in developing countries and in the United States: 1. The World Health Organization solution (oral rehydrating solution) containing 90 mmol/L sodium, 20 mmotfL potassium, plus base and glucose at 111 mmolfL (2%) is a suitable oral rehydrating solution for infantile dehydration with hypovolemia regardless of the cause of the dehydration or the nature of the physiologic disturbance (serum sodium concentration). The volume to be administered should be judged clinically to replace the estimated deficit. 2. Maintenance of hydration (or prevention of dehydration) during diarrhea may appropriately utilize the W H O ORS by giving additional free water to the infants. This may be by ad libitum breast-feedings, by one part plain (or flavored) water for two parts ORS, or by juices, preferably those containing potassium. When plain water is used, potassium-containing foods should be offered as soon as possible. 3. Alternatively, in those regions such as the United States or wherever economically and logistically feasible, a separate maintenance and prevention solution may be used. This solution should differ from many present commercial oral electrolyte solutions by having: a lower glucose or other suitable carbohydrate concentration, e.g., 111 mmol/L of glucose; a higher sodium concentration, e.g., 50 to 60 mmol/L; a potassium concentration of 20 to 30 mmol/L; and anions as chloride (30 to 50 mmol/L) and base (e.g., bicarbonate or citrate, 30 mmol/L). Such a solution is well suited for replacement of stool losses in infantile enteritis from viral and bacterial causes. At the same time, there is adequate free water to allow excretion of what will sometimes be an excess of electrolyte. As an additional precaution, when prescribing such a solution for prevention, the daily volume should be limited (usually 150 ml/kg/day) and the caretaker instructed to administer any additional fluid as plain water or human milk to satisfy thirst. Acute diarrheal disease is known to contribute significantly to the development and progression of malnutrition
Volume 101 Number 4
in children. One of the goals of therapy is, therefore, to minimize these adverse effects through the promotion of optimal nutritional intake during and immediately following episodes of diarrhea. The use of the oral glucoseelectrolyte solutions aids in these endeavors through the rapid restoration of homeostasis which in turn makes it possible for the child to resume food intake as well. Glucose in the oral treatment solutions is not itself a significant source of calories, although its absorption, which remains relatively intact during a diarrheal episode, enables the coupled absorption of sodium and water to occur. Although temporary lactase deficiency is a wellrecognized feature of acute diarrheas of all causes, there is no suggestion that the continuation of breast-feeding during a diarrheal episode is harmful, and therefore, this practice is to be encouraged. On the other hand, for reasons not well known, cow milk and lactose-containing formulas may not be so well tolerated during and immediately following an acute diarrheal episode. Although no definitive data are available, it seems appropriate, in non-breast-fed infants with moderate to severe diarrhea, to avoid the use of lactose-containing milk or formulas for one or two days and then to resume milk feedings cautious-
Oral rehydration f o r diarrhea
499
ly. Cereals (rice, wheat noodles), bananas, potatoes, and other nonlaetose, carbohydrate-rich foods can be offered during this period after the initial few hours of rehydration with oral electrolyte solution. Unfortunately, the optimal dietary methods to use during this time are not yet well worked out. There is evidence, however, that many digestive and absorptive processes in the intestine are normal or near normal (monosaccharride, amino acids) during an episode of diarrhea, and it is therefore encouraging to think that satisfactory methods that make use of locally available foods will almost certainly be developed. Fasting beyond the initial rehydration period is not indicated (except under special circumstances) and, in children with borderline nutritional status, may be particularly detrimental. After the initial replacement of fluid and electrolyte losses, age-appropriate food should be provided as soon as it can be accepted by the child. Oral rehydration therapy is effective, safe, and inexpensive. Its extensive use should result in a decrease in the need for hospitalization, and in the reduction of the deleterious effects of acute diarrhea on nutrition and on the mortality rate.