The nurse is examining a 12-month-old who was brought to the clinic for persistent, painful diaper rash after being treated for otitis media with antibiotics. The nurse finds red perianal inflammation with satellite lesions. This is most likely caused by:

Choice A reason: This is the correct statement, as the knee-chest position can help reduce the cyanosis and hypoxia in infants with tetralogy of Fallot. This position increases the systemic vascular resistance and decreases the right-to-left shunting of blood, improving the pulmonary blood flow and oxygenation¹².

Choice B reason: This is not a correct statement, as the Trendelenburg position can worsen the cyanosis and hypoxia in infants with tetralogy of Fallot. This position decreases the systemic vascular resistance and increases the right-to-left shunting of blood, reducing the pulmonary blood flow and oxygenation¹².

Choice C reason: This is not a correct statement, as feeding the infant every 2 hours around the clock can cause overfeeding and fatigue in infants with tetralogy of Fallot. These infants may have poor appetite and weight gain due to their cardiac condition, and they may need frequent rest periods during feeding. Feeding the infant on demand or every 3 to 4 hours may be more appropriate¹³.

Choice D reason: This is not a correct statement, as adding rice cereal to the formula can increase the risk of aspiration and choking in infants with tetralogy of Fallot. These infants may have difficulty swallowing and coordinating their breathing, and they may need a thin and easily digestible formula. Adding rice cereal to the formula may also increase the caloric density and volume, which can cause overfeeding and fatigue¹³.

Choice A reason: Mechanical ventilation does not necessarily increase the fluid requirements of a child. Mechanical ventilation is a method of providing artificial breathing support to a child who has respiratory failure or insufficiency. Mechanical ventilation may affect the fluid balance of a child by altering the insensible losses, the renal function, or the hemodynamics. However, the net effect may vary depending on the type, mode, and settings of the ventilator, as well as the underlying condition of the child. Therefore, the fluid requirements of a child on mechanical ventilation should be individualized and monitored closely¹.

Choice B reason: Increased intracranial pressure (ICP) does not increase the fluid requirements of a child. Increased ICP is a condition in which the pressure inside the skull is higher than normal, due to various causes such as head injury, brain tumor, infection, or hydrocephalus. Increased ICP may affect the fluid balance of a child by impairing the cerebral blood flow, the cerebrospinal fluid drainage, or the hypothalamic-pituitary axis. However, the net effect may vary depending on the severity, duration, and cause of the increased ICP, as well as the presence of other complications such as cerebral edema or diabetes insipidus. Therefore, the fluid requirements of a child with increased ICP should be individualized and monitored closely².

Choice C reason: Congestive heart failure does not increase the fluid requirements of a child. Congestive heart failure is a condition in which the heart is unable to pump enough blood to meet the body's needs, due to various causes such as congenital heart defects, cardiomyopathy, or infection. Congestive heart failure may affect the fluid balance of a child by causing fluid retention, edema, or pulmonary congestion. However, the net effect may vary depending on the type, severity, and stage of the heart failure, as well as the presence of other complications such as renal failure or liver failure. Therefore, the fluid requirements of a child with congestive heart failure should be individualized and monitored closely³.

Choice D reason: Fever increases the fluid requirements of a child. Fever is a condition in which the body temperature is higher than normal, due to various causes such as infection, inflammation, or immunization. Fever increases the fluid requirements of a child by increasing the metabolic rate, the insensible losses, and the urine output. The amount of fluid loss due to fever depends on the degree and duration of the fever, as well as the ambient temperature and humidity. A general rule of thumb is that for every degree Celsius increase in body temperature, the fluid requirements increase by 10%⁴. Therefore, the fluid requirements of a child with fever should be adjusted and monitored closely.