One of the major objectives of parenteral fluid therapy is provision of water to meet physiologic losses. These losses, the insensible and urinary losses, have been extensively studied and defined for infants and adults. It is established from these studies that both insensible loss of water and urinary water loss roughly parallel energy metabolism and do not parallel body mass (weight). Therefore, any values that are applicable to all ages must be derived from some function of energy metabolism.
Initially, and to a large extent even today, needs for water have been determined on the basis of weight in infants and on the basis of total amounts in adults. Although this serves well for infants and adults, the hapless individual between these two groups receives, at best, a rough estimate of his requirement for water.
Crawford and his associates have referred needs for water, and a variety of drug dosages as well, to a unit of surface area (SA) because SA closely parallels basal energy metabolism. In this system SA is computed from a height-weight nomogram.
It is generally agreed that the maintenance requirements for water of individuals is determined by their caloric expenditure. By means of the following formulae, the caloric expenditure of hospitalized patients can be determined from weight alone. For weights ranging from 0 to 10 kg, the caloric expenditure is 100 cal/kg/day; for weights ranging from 10 to 20 kg the caloric expenditure is 1000 cal plus 50 cal/kg for each kilogram of body weight >10; for weight >20 kg the caloric expenditure is 1500 cal plus 20 cal/kg for each kilogram >20.
Maintenance requirements for water depend on insensible loss of water and renal loss. An allowance of 50 mL/100 cal/day will replace insensible loss of water, and 66.7 mL/100 cal/day will replace renal losses. As water of oxidation will supply approximately 16.7 mL/100 cal/day, the remaining 100 mL/100 cal/day must be supplied to meet the remaining water losses of patients on parenteral fluid therapy. Possible exceptions to this figure are discussed.
Maintenance requirements of sodium, chloride, and potassium are 3.0, 2.0, and 2.0 mEq/100/cal/day, respectively.
In the category of genitourinary and fluid and electrolyte disorders, no paper bridges the discoveries of the 1930s through the 1950s, and the practice of today as does this classic paper of Holliday and Segar.1 A house officer or pediatric staff physician still uses this simple method of estimating the insensible and urinary water needs of a child of any size or age daily. Current textbooks and the latest editions of commonly used house officer manuals use this method of determining maintenance water needs based on calorie expenditure.2-5 This method involves a simple-to-use formula that relates to the average calorie expenditure of a child of a given weight in kg. The infant up to 10 kg in weight expends 100 kcal/kg; the child from 10 to 20 kg expends 1000 kcal plus 50 kcal/kg and in the child weighing more than 20 kg, the expenditure is 1500 kcal plus 20 kcal per kg. The allowance of 50 mL/kg/24 hours will replace insensible losses and 66.7 ml/kg/24 hours will replace urinary losses so that 110 to 120 mL/100 kcal expended every 24 hours meets appropriate water maintenance needs.
Drs Holliday and Segar were the students of several giants of the fluid and electrolyte field: Drs James L. Gamble, Daniel C. Darrow, Robert E. Cooke, William M. Wallace, and Allen M. Butler. These pediatric clinician scholars defined the nature of fluid and electrolyte balance in man and in children of all ages, understanding the relationship of intracellular space, extracellular space, intravascular space, and the ionic composition of each. These investigators and their students studied the variation in the requirements for water and electrolytes under a variety of clinical situations including diarrhea, dehydration, the acidosis of infancy because of diarrhea, burns, and bowel surgery. The remarkable simultaneous finding of two children with massive bowel chloride losses or congenital chlorideorrhea still bears the name of the Darrow-Gamble syndrome to honor these remarkable pediatric scientists.6
Drs Holliday and Segar were young faculty members at the University of Indiana when they developed a formula to define the maintenance needs for water in parenteral fluid therapy.1This paper is more a compilation of information gained in metabolic units in New Haven, New York, and Boston, rather than relying on completely new information. An important feature of this paper is the comparison of four distinct systems of measuring water needs: 1) the need for water estimated to be 100 mL/100 kcal; 2) the need for water to be 1500 mL/m2/24 hours; 3) the need for water estimated to be 120 mL/100 kcal dependent on basal and “activity” calories; and 4) the need for water estimated by age and calories. In Table II in the paper, Holliday and Segar showed by comparison of the various methods of calculation that a similar volume of water was required for a given patient. In their paper, Holliday and Segar proposed a remarkably simple method of defining maintenance water needs that was totally practical, but remarkably precise. In a letter written by Dr Bill Wallace, a reviewer of the paper for the journal, he marvelled at how many aspects of water needs were uncovered that had not been precisely examined previously (M. A. Holliday, personal communication, 1997). Wallace noted, “I think people have been confined by attempting to make something very precise which does not need to be so. Like weighing a truck on an analytical balance.”
With the development of both total parenteral nutrition therapy and oral rehydration of diarrhea under field conditions,7,8 the maintenance needs for water still remain the same. Recent studies of water needs have proven the usefulness of the method of Holliday and Segar.9 This method is simple, but it is based on profound biologic and physiochemical principles.
- Holliday MA,
- Segar WE
- ↵Nelson Textbook of Pediatrics. Behrman RE, Kleigman RM, Arvin AM, Nelson E, eds. 15th ed. Philadelphia, PA: WB Saunders; 1996:206–208
- ↵Rudolph's Pediatrics. Rudolph AM, Hoffman JIE, Rudolph CD, eds. Stanford, CT: Appleton and Lange; 1996:1321
- ↵The Harriet Lane Handbook: A Manual for Pediatric House Officers. Barone MA, ed. St Louis, MO: Mosby; 1996:216–217
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- ↵The Metabolic and Molecular Bases of Inherited Disease. Scriver CR, Beaudet AM, Sly C, Valle D, eds. 7th ed. 1995:385–400
- ↵Clinical Nutrition of the Young Child. Brunser, Carrazza R, Gracey, Nichols L, Senterre. New York, NY: Raven Press; 1991:252–254
- ↵Kidney Electrolyte Disorders. Chan JCM, Gill JR Jr, Brunser O, Carrazza FR, Gracey M, Nichols BL, Senterre J. New York, NY: Churchill Livingstone; 1990:343–363
- ↵Manual of Preoperative and Postoperative Care. Committee on Preoperative and Postoperative Care, American College of Surgeons. Philadelphia, PA: WB Saunders; 1983:300–301
- Copyright © 1998 American Academy of Pediatrics