The Child with Fluid and Electrolyte Imbalance 24

Treatment of shock consists of three major goals,

(1) ventilation, (2) fluid administration, and (3) improvement of the pumping action of the heart (vasopressor support).

Table 24-1 Daily maintenance fluid requirements

1-10 kg= 100 ml/kg 11-20 kg=1000 ml + 50 ml/kg for each kg>10 kg >20 kg=1500 ml + 20 ml/kg for each kg>20 kg

Burns are assessed on

the extent, depth, and severity of the wound. The severity of the burn injury is assessed on the basis of the percentage of TBSA burned and depth of the burn. Traditionally, the terms first, second, third, and fourth degree have been used to describe the depth of tissue injury. However, with the current emphasis on wound healing, this traditional terminology is being replaced by more descriptive terms related to the extent of destruction to the epithelializing elements of the skin. In general: • First-degree burns are classified as superficial. • Second-degree burns are classified as partial-thickness wounds. Partial-thickness wounds are further classified as superficial or deep in relation to the time required for healing to occur and the functional and cosmetic results anticipated. • Third- and fourth-degree burns are classified as full-thickness wounds. Full-thickness (third-degree) burns are serious injuries that involve the entire epidermis and dermis and extend into subcutaneous tissue.

ICF intracellular fluid

the fluid contained with in the cells

ECF extracellular fluid

the fluid outside the cells

The extent of the burn is expressed as a percentage of

total body surface area (TBSA) injured. A child has different body proportions than an adult, resulting in inaccurate estimation of injury if the standard adult rule of nines is used. The proportions of the child's trunk and arms are roughly the same as those of the adult. However, an infant's head and neck make up 18% of the TBSA, and each lower extremity accounts for 14% of the TBSA. A modified rule of nines for the pediatric population proposes that for each year of life after age 2 years, 1% is deducted from the head and 0.5% is added to each leg.

Nursing assessment of fluid and electrolyte disturbances entails observation of

general appearance, vital signs, daily weights, intake and output measurement, and review of relevant laboratory results.

Nursing Alert!

in a child with a history of fluid loss and potential or actual dehydration, gear nursing assessment toward the possibility of impending shock.

Shock or circulatory failure is a complex clinical syndrome characterized by

inadequate tissue perfusion to meet the metabolic demands of the body, resulting in cellular dysfunction and eventual organ failure. Although the causes are different, the physiologic consequences are the same and include hypotension, tissue hypoxia, and metabolic acidosis. The three main types of shock are hypovolemic, distributive, and cardiogenic.

nurses should be alert for altered fluid requirements in various conditions

increased requirements: -fever (add 12% per rise of 1 degree Celsius) -vomiting, diarrhea -high-output kidney failure -diabetes insipidus -diabetic ketoacidosis -burns -shock -tachypnea -radiant warmer (preterm infant) -phototherapy (infants -postoperative bowel surgery (e.g. gastroschisis) Decreased requirements -heart failure -syndrome of inappropriate antidiuretic hormone -mechanical ventilation -after surgery -oliguric renal failure -increased intracranial pressure

Edema formation is caused by

increased venous pressure, capillary permeability, diminished plasma proteins, lymphatic obstruction, or decreased tissue tension. Generalized edema is manifested by swelling in the extremities, face, perineum, and torso. Loss of normal skin creases may be assessed. In children, daily weights are sensitive indicators of water gain or loss.

Parenteral fluid therapy

is initiated to meet ongoing daily physiologic losses, restore previous deficits, and replace ongoing abnormal losses. The initial phase is to expand extracellular fluid volume quickly and to improve circulatory and renal function. During initial therapy, an isotonic electrolyte solution is used at a rate of 20 ml/kg, given as an intravenous (IV) bolus over 5 to 20 minutes and repeated as necessary after assessment of the child's response to therapy. Subsequent therapy is used to replace deficits, meet maintenance water and electrolyte requirements, and catch up with ongoing losses. Oral fluids are started in small amounts when the child's status allows. If the child is able to eat, a regular diet is initiated and maintained as tolerated.

Anaphylaxis

is the acute clinical syndrome resulting from the interaction of an allergen and a patient who is hypersensitive. This antigen-antibody (immunoglobulin E) reaction stimulates the release of chemical substances, primarily histamine, from mast cells. Prevention of a reaction is the primary goal.

Dehydration may be classified as:

isotonic, hypotonic, or hypertonic. • Isotonic dehydration occurs in conditions in which electrolyte and water deficits are present in approximately balanced proportions. This is the primary form of dehydration occurring in children. • Hypotonic dehydration occurs when the electrolyte deficit exceeds the water deficit. • Hypertonic dehydration results from water loss in excess of electrolyte loss and is usually caused by a proportionately larger loss of water or a larger intake of electrolytes. This type of dehydration is the most dangerous and requires much more specific fluid therapy.

Water intoxication

may occur in small children with an elevated intake of electrolyte-free fluids. Children who ingest excessive amounts of electrolyte-free water develop a concurrent decrease in serum sodium accompanied by central nervous system (CNS) symptoms. There is a large urinary output and, because water moves into the brain more rapidly than sodium moves out, the child may also exhibit irritability, somnolence, headache, vomiting, diarrhea, or generalized seizures. Fluid intoxication can occur during acute IV water overloading, too rapid dialysis, tap water enemas, feeding of incorrectly mixed formula, or excess water ingestion or with too rapid reduction of glucose levels in diabetic ketoacidosis.

Total body water

ranges from 45% (late adolescence) to 75%(term newborn) of total body weight

For a child with mild to moderate dehydration, oral rehydration may be sufficient to replenish fluids lost. This management consists of

replacement of fluid loss over 4 to 6 hours, replacement of continuing losses, and provision for maintenance fluid requirements. In general, whereas a mildly dehydrated child may be given 50 ml/kg of oral rehydration solution (ORS), the child with moderate dehydration may be given 100 ml/kg of ORS.

Burn injuries

represent one of the most severe traumas a body can sustain. Ongoing efforts toward education, burn prevention, safer home and work environments, and new methods of firefighting have significantly decreased burn injuries.

Essential emergency care of burn injury includes

stopping the burning process, covering the burn, transporting the injured child to medical aid, and providing reassurance to the child and family. Thermally injured children are subject to a number of serious complications, both from the wound and from systemic alterations resulting from the injury. The immediate threat to life is related to airway compromise and profound shock.

Fluid depletion

Infants are subject to fluid depletion because of their relatively greater surface area, their high rate of metabolism, and their immature kidney function. Compared with older children and adults, infants have a greater fluid intake and output relative to size. Water and electrolyte disturbances occur more frequently and more rapidly, and infants and small children adjust less promptly to these alterations.

The mother asks about giving the children antidiarrheal medications. The nurse's response should be based on knowledge that these medications are A. not recommended. B. recommended for children over age 6 months. C. recommended for children over age 1 year. D. recommended for children over age 4 years.

The correct answer is A. Rationale: A-D. Antidiarrheal agents are not indicated in acute infectious diarrhea in infants and young children because of the toxicity and adverse effects that may occur, such as worsening of the diarrhea because of slowing of motility and ileus or a decrease in diarrhea, with continuing fluid losses and dehydration.

The mother asks about giving Brian food after he is rehydrated. Which of the following is the most appropriate recommendation? A. Offer a regular diet. B. Offer a regular diet except high-protein foods. C. Give clear liquids for the next 24 hours. D. Start the BRAT diet (bananas, rice, applesauce, and toast).

The correct answer is A. Rationale: A-D. Early reintroduction of a regular diet, including protein-containing foods, is an important aspect of treatment of acute diarrhea in children. It provides nourishment and prevents malnutrition. The BRAT diet is avoided because it is low in energy and protein, too high in carbohydrates, and low in electrolytes.

Brian is 4 years old, and his brother, Adam, is 5 months old. Both children are brought to the clinic by their mother because of diarrhea and fever. Brian has also vomited twice. The nurse assesses the children and determines that they are mildly dehydrated. Which of the following is the most appropriate method of rehydrating Brian? A. Administer intravenous fluids. B. Give an oral rehydration solution. C. Give soft drinks that have been diluted and decarbonated. D. Give small amounts of gelatin or clear liquids such as juice and water.

The correct answer is B. Rationale: A. Intravenous fluids are only required when the child is unable to ingest sufficient amounts of fluids and electrolytes to meet ongoing daily physiologic losses, replace previous deficits, and replace ongoing abnormal losses; this method is not usually required for mild dehydration. B. Oral rehydration solutions are successful in treating the majority of children with isotonic, hypotonic, or hypertonic dehydration. C. Soft drinks are usually high in carbohydrates, low in electrolytes, and high in osmolality; therefore, they are not effective solutions for rehydration. In addition, caffeinated sodas should be avoided because of the diuretic effect of caffeine, which may lead to an increased loss of water and sodium. D. Clear liquids such as fruit juices and gelatin are not used for rehydration because of their high carbohydrate content, very low electrolyte content, and high osmolality.

The mother asks what to do about breastfeeding Adam. The nurse should recommend that she A. stop breastfeeding for 24 hours. B. stop breastfeeding until diarrhea stops. C. bottle feed glucose water, alternating it with breastfeeding. D. continue breastfeeding and give an oral rehydration solution to replace diarrheal losses.

The correct answer is D. Rationale: A-D. Breastfeeding should be continued because of its potential to reduce the severity and duration of the illness. Oral rehydration solutions can be given in addition to breastfeeding to replace ongoing losses.

Box 24-1 Internal control mechanisms influencing fluid balance

Thirst- the impetus to ingest water is stimulated by increased solute concentration (osmolality) of extracellular fluid and or diminished intravascular volume Antidiuretic hormone (ADH)- ADH is released from the posterior pituitary gland in response to increased osmolality and decreased volume of intravascular fluid; it promotes water retention in the renal system by increasing the permeability of renal tubule to water. Aldosterone- is secreted by the adreanal cortex; it enhances sodium reabsorption in renal tubules, thus promoting osmotic reabsorption of water. Renin-angiotensin system- Diminished blood flow to the kidneys stimulates renin secretion, which reacts with plasma globulin to generate angiotensin, a powerful vasoconstrictor. angiotensin also stimulates the release of aldosterone.

what is the most important determinant of the percent of total body fluid loss in infants and younger children?

Weight

The nurse is caring for a 12-year-old boy who sustained major burns when he put charcoal lighter on a campfire. The nurse observes that he is "very brave" and appears to accept pain with little or no response. The most appropriate nursing action related to this is which of the following? a. Request a psychologic consultation. b. Ask the child why he doesn't have pain. c. Praise the child for ability to withstand pain. d. Encourage continued bravery as a coping strategy.

a. A psychologic consultation will help the child verbalize fears. Children in this age group are concerned with physical appearance. The psychologists can help integrate the issues that the child is facing. It is likely that the child is having pain but not acknowledging the pain. If the child is feeling pain, the nurse should not praise him for hiding it. Encouraging continued bravery may not be an effective coping strategy if the child is in severe pain.

Preventing exposure to an allergen is more easily accomplished in children known to be at risk, including those with

(1) a history of a previous allergic reaction to a specific antigen, (2) a history of allergy (atopy), (3) a history of severe reactions in immediate family members, and (4) a reaction to a skin test (although skin tests are not available for all allergens).

Management of major burns consists of

facilitating wound healing, relieving discomfort, replacing destroyed skin, preventing or treating complications, and providing rehabilitation. After the initial period of shock and restoration of fluid balance, the primary concern is the burn wound. The primary goal for burn wound management is to close the wound as soon as possible. The objectives of wound management include prevention of infection, removal of devitalized tissue, and closure of the wound. The application of dressings and topical antimicrobial therapy reduce pain by minimizing air exposure.

Fluid disturbances

Fluid disturbances experienced by children are dehydration, water intoxication, and edema.

An adolescent girl is cooking on a gas stove when her bathrobe catches fire. Her father smothers the flames with a rug and calls an ambulance. She has sustained major burns over much of her body. Which of the following is also important in her immediate care? a. Cool with a single application of tepid water. b. Encourage her to drink clear liquids. c. Remove her burned clothing and jewelry. d. Leave the rug in place until the ambulance arrives.

a. In major burns, additional applications of cool water lead to a drop in body temperature and potential circulatory collapse. Nothing is given by mouth because of the risk of aspiration in the presence of a paralytic ileus. As much of her clothing should be removed as possible.

Which of the following occurs in septic shock? a. Massive vasodilation b. Increased respiratory rate c. Decreased capillary permeability d. Increased systemic vascular resistance

a. In septic shock, an infection triggers an inflammatory response, which results in massive vasodilation and increased capillary permeability. Respirations are not affected. Capillary permeability is increased. Vasodilation results in decreased systemic vascular resistance.

What type of dehydration is defined as "dehydration that occurs in conditions in which electrolyte and water deficits are present in approximately balanced proportion?" a. Isotonic dehydration b. Hypotonic dehydration c. Hypertonic dehydration d. All types of dehydration in infants and small children

a. Isotonic dehydration is the correct term for this definition and is the most frequent form of dehydration in children. Hypotonic dehydration occurs when the electrolyte deficit exceeds the water deficit, leaving the serum hypotonic. Hypertonic dehydration results from water loss in excess of electrolyte loss and is usually caused by a proportionately larger loss of water or a larger intake of electrolytes. "Dehydration that occurs in conditions in which electrolyte and water deficits are present in approximately balanced proportion" is a definition specific to isotonic dehydration.

The nurse is assessing an infant brought to the clinic with diarrhea. He is lethargic and has dry mucous membranes. Which of the following should the nurse recognize as an early sign of dehydration? a. Tachycardia b. Bulging, tense fontanel c. Decreased blood pressure d. Capillary refill of less than 3 seconds

a. Tachycardia is the earliest manifestation of dehydration. Fever and infection can also result in tachycardia, so these should be included **********essment data. A bulging fontanel may be indicative of increased intracranial pressure, not dehydration. Decreased blood pressure is a late sign of dehydration. Capillary refill is slowed and more than 3 seconds in dehydration.

Burns

are caused by thermal, chemical, electric, or radioactive agents. The physiologic responses, therapy, prognosis, and disposition of the injured child are all directly related to the amount of tissue destroyed.

Rapid replacement of fluid is essential in the treatment of which of the following types of dehydration? a. Isotonic, osmotic b. Hypotonic, isotonic c. Osmotic, hypertonic d. Hypertonic, hypotonic

b. In moderate to severe dehydration, rapid expansion of the intravascular space is necessary. Rapid replacement is indicated in isotonic dehydration. Osmotic is not a type of dehydration. Rapid replacement is contraindicated in hypertonic dehydration.

Which of the following statements regarding burn injuries in children is correct? a. Burns are the most frequent cause of accidental death during childhood. b. The prognosis for a burned child is directly related to the amount of tissue destroyed. c. The standard "rule of nines" chart is typically used for assessing the size of a burn in small children. d. Children younger than age 2 years have significantly lower mortality rates than older children with similar burns.

b. The prognosis of a child with a burn is directly related to the amount of tissue destroyed. The location of the wounds, age of the child, causative agent, respiratory involvement, general health of the child, and other injuries are also considered. Burned clothing is removed to prevent further damage from smoldering fabric and hot beads of synthetic fabric. Jewelry is removed to stop the transfer of heat from the metal to the skin. Burn and fire injuries are the third leading cause of unintentional injury-related death in children younger than the age of 14 years. The body proportions of the child are different from those of an adult. Use of the standard adult rule of nines will give an inaccurate estimate of the burn area. Physiologic factors, including greater relative percentage body water, minimum protein stores, and an immature immune response, contribute to a significantly higher mortality in children younger than age 2 years.

To prevent burns from hot water in the home, the nurse should recommend that families set their water heater thermostat to a. 38º C (100º F). b. 49º C (120º F). c. 60º C (140º F). d. 71º C (160º F).

b. The recommended temperature to set water heaters is 120º F. A water heater can be set 10 degrees higher and still be safe. Temperatures of 60º C (140º F) to 71º C (160º F) are too high. At 140º F, submersion for 5 seconds will cause a burn.

Which of the following is defined as the forces that favor filtration from the capillary? a. Diffusion and osmosis b. Active transport c. Capillary hydrostatic pressure and interstitial oncotic pressure d. Hydrostatic pressure

c. Capillary hydrostatic pressure and interstitial oncotic pressure are forces that favor filtration from the capillary. Diffusion is the random movement of molecules from a region of greater concentration to regions of lower concentration, and osmosis is the physical force created by a solution of higher concentration across a semipermeable membrane. Active transport is movement of a substance against a pressure gradient from an area of lesser or equal concentration to an area of greater or equal concentration. A carrier substance is needed. Hydrostatic pressure is the pressure in the arterial portion of the circulatory system, which can push fluid through the capillary walls.

Depression of the central nervous system (CNS), manifested by lethargy, delirium, stupor, and coma, is observed in which of the following? a. Metabolic acidosis b. Respiratory alkalosis c. Metabolic and respiratory acidosis d. Metabolic and respiratory alkalosis

c. Hydrogen ion imbalances result in CNS involvement. Depression of the CNS, as manifested by lethargy, delirium, diminished mental capacity, stupor, and coma, is found in acidosis that is either metabolic or respiratory in origin. Respiratory acidosis can also manifest these clinical findings. Respiratory and metabolic alkalosis are reflected clinically by CNS excitation and stimulation, nervousness, tingling sensations, and tetany that may progress to seizures.

Which of the following is a major complication of total parenteral nutrition in children? a. Anemia b. Asthma c. Liver disease d. Renal impairment

c. Liver disease is the most important gastrointestinal complication of total parenteral nutrition. If present, anemia and asthma are not directly related to the total parenteral nutrition. Renal function is monitored to ensure electrolyte balance, but impairment is not an expected complication.

When caring for a child with an intravenous infusion, the nurse should do which of the following? a. Change the insertion site every 24 hours. b. Use a macrodropper to facilitate the prescribed flow rate. c. Observe the insertion site frequently for signs of infiltration. d. Avoid restraining the child to prevent undue emotional stress.

c. The nursing responsibility for intravenous therapy is to calculate the amount to be infused in a given length of time; set the infusion rate; and monitor the apparatus frequently, at least every 1 to 2 hours, to make certain that the desired rate is maintained, the integrity of the system remains intact, the site remains intact (free of redness, edema, infiltration, or irritation), and the infusion does not stop. Insertion sites do not need to be changed every 24 hours unless a problem is found with the site. This exposes the child to significant trauma. If an infusion pump is not used, a minidropper (60 drops/ml) is the recommended intravenous tubing in children. The intravenous site should be protected. This may require soft restraints on the child.

Several types of long-term central venous access devices are used. Which of the following is a benefit of using an implanted port (e.g., Port-a-Cath)? a. Accessed without piercing skin b. Easy to use for self-administered infusions c. Easy access for blood work d. Catheter unable to dislodge from port even if the child "plays" with the port site

c. The port is completely under the skin. Other advantages include cosmetic appearance and easy access for blood work and fluid and medication administration. The skin must be accessed with a special needle before the infusion can begin. Placement in the chest makes it difficult to use for self-administered injections. The catheter can be dislodged from the port if the child rubs the port site.

Treatment of burns classified as minor

can usually be managed adequately on an outpatient basis when it is determined that the parent can be relied on to carry out instructions for care and observation. Management of minor burns consists of facilitating wound healing, relieving discomfort, and preventing complications.

Shock can be regarded as a form of compensation for circulatory failure and, because of its progressive nature, can be divided into two stages or phases,

compensated and hypotensive (formerly decompensated). At all stages, the principal differentiating signs are the (1) degree of tachycardia and perfusion to extremities, (2) level of consciousness, and (3) systemic blood pressure. Additional signs or modifications of these more universal signs may be present depending on the type and cause of the shock.

Which of the following should the nurse recognize as an early clinical sign of compensated shock in a child? a. Confusion b. Sleepiness c. Hypotension d. Apprehension

d. Early signs are vague and subtle, including apprehension, irritability, normal blood pressure, narrowing pulse pressure, thirst, pallor, and diminished urinary output. Confusion, sleepiness, and hypotension are later signs of shock.

In which of the following conditions is the fluid requirement for children decreased? a. Burns b. Fever c. Vomiting d. Increased intracranial pressure

d. When there is a risk of increased intracranial pressure, the child's fluid balance is carefully monitored to ensure that only required fluids are given. With burns, fever, and vomiting, the child loses fluids at a greater than expected rate. Supplemental fluids need to be given to avoid the risk of dehydration.