Skip to Main Content

Chapter 132: Fluid and Electrolyte Therapy in Infants and Children

Melissa Chan; Paul Enarson

INTRODUCTION

This chapter provides a basic guide to parenteral rehydration, maintenance fluids, and management of common electrolyte abnormalities in children.

The most common cause of fluid and electrolyte abnormalities in children is dehydration. Dehydration results from a negative fluid balance due to decreased intake, increased output (renal, GI, or insensible losses from the skin or respiratory tract), or disease states such as burns, sepsis, or diabetes. Negative fluid balance can occur in the intracellular fluid or extracellular fluid compartments and may be accompanied by derangements in electrolytes. Table 132-1 lists some of the common causes of dehydration. Common signs of dehydration are listed in Table 132-2, and a validated clinical scoring system predicting the need for parenteral rehydration is provided in Table 131-6.

TABLE 132-1Causes of Dehydration in Children
View Table||Download (.pdf)
TABLE 132-1 Causes of Dehydration in Children

Decreased Intake:

  • Voluntary or involuntary

    • Anatomic or pathologic diseases (pharyngitis, stomatitis, cleft lip/palate, facial dysmorphism, airway obstruction)

    • Neurologic diseases (meningitis, encephalitis, brain tumor, seizures)

    • Febrile illnesses

Increased Output:

  • Insensible losses (fever, heat, respiratory diseases, diaphoresis, thyroid disease, cystic fibrosis)

  • GI losses (vomiting, diarrhea)

  • Renal losses:

    Osmotic (DKA, acute tubular necrosis)

    Nonosmotic (renal diseases, electrolyte disturbance, diabetes insipidus)

  • Sodium losing (adrenal disease, diuretics, kidney disease, pseudohypoaldosteronism)

Systemic Diseases:

  • Moderate to severe burns

  • Ascites

  • Respiratory disease

  • Peritonitis: medical or surgical with third spacing

  • Anaphylaxis

Abbreviation: DKA = diabetic ketoacidosis.

TABLE 132-2Clinical Guidelines for Assessing Dehydration in Children
View Table||Download (.pdf)
TABLE 132-2 Clinical Guidelines for Assessing Dehydration in Children
  None to Minimal Dehydration (<3% loss of body weight) Some (mild to moderate) Dehydration (3% to 9% loss of body weight) Severe Dehydration (>9% loss of body weight)
Mental status Well, alert Fatigued, restless, irritable Apathetic, lethargic, unconscious
Thirst Normal, slight increase, or refusing fluids Increased, eager to drink Very thirsty or too lethargic to indicate
Heart rate Normal Normal to increased Tachycardic with bradycardia in severe cases
Blood pressure Normal Normal Normal to reduced
Pulse quality Normal Normal to reduced Weak, thready
Breathing Normal Normal to tachypneic Deep
Eyes Normal Slightly sunken orbits Deeply sunken orbits
Tears Present Decreased Absent
Mucous membranes Moist Dry Parched
Anterior fontanelle Normal Sunken Sunken
Skin turgor Instant recoil Recoil in <2 s Recoil in >2 s
Capillary refill Normal Prolonged 1–2 s Prolonged >2 s
Extremities Warm Cool Cold, mottled, cyanotic
Urine output Normal to decreased Decreased (<1 mL/kg/h) Minimal (<0.5 mL/kg/h)

Courtesy of Stephen Freedman, MD, and Jennifer Thull-Freedman, MD.

PATHOPHYSIOLOGY

Infants and children are particularly susceptible to dehydration for a number of developmental and physiologic reasons. They are dependent on caretakers to provide oral fluids and therefore cannot regulate their intake. In addition, young children and infants have increased fluid requirements and are at risk of increased fluid losses compared to adults and ...

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.

This site uses cookies to provide, maintain and improve your experience. MH Privacy Center Close