A nurse is admitting a 6-month-old infant who has dehydration. Which of the following amounts of urinary output should indicate to the nurse that the treatment has corrected the fluid imbalance?

Choice A reason: Increased appetite is not a common finding in children with brain tumors. On the contrary, they may have decreased appetite, nausea, vomiting, or weight loss due to increased intracranial pressure or tumor location.

Choice B reason: Negative Babinski reflex is a normal finding in children over 2 years old and adults. It means that the toes curl downward when the sole of the foot is stimulated. A positive Babinski reflex, which means that the big toe moves upward and the other toes fan outward, is a sign of damage to the corticospinal tract, which may be caused by a brain tumor.

Choice C reason: Tachycardia, or rapid heart rate, is not a specific finding for brain tumors. It may be caused by many factors, such as fever, pain, anxiety, dehydration, or medications. However, some brain tumors may affect the autonomic nervous system, which regulates the heart rate, and cause bradycardia, or slow heart rate.

Choice D reason: Hyporeflexia, or diminished reflexes, is a possible finding in children with brain tumors. It indicates a dysfunction of the lower motor neurons, which may be affected by the tumor or the increased intracranial pressure. Hyporeflexia may manifest as weakness, numbness, or decreased muscle tone in the affected limbs.

The correct answer is: b.

Choice A: Heart rate 130/min

A heart rate of 130 beats per minute (bpm) is considered high for a 3-year-old child. Normal heart rates for children aged 1-3 years typically range from 80 to 120 bpm. While dehydration can cause tachycardia (increased heart rate), a heart rate of 130 bpm does not necessarily indicate effective rehydration.

Choice B: Urine specific gravity 1.015

Urine specific gravity of 1.015 is within the normal range (1.005–1.030) for a hydrated child. Dehydration increases urine concentration (>1.020), but a normalized value like 1.015 shows that ORT has restored fluid balance. UpToDate and NIH studies (e.g., Binder et al., 2014) highlight urine specific gravity as a precise measure of hydration status, making it the strongest indicator of ORT effectiveness.

Choice C: Respiratory rate 24/min

The normal respiratory rate for a 3-year-old child is between 20 and 30 breaths per minute. A respiratory rate of 24 breaths per minute is within this normal range. While a normal respiratory rate can indicate improved hydration status, it is not the most specific indicator of effective rehydration therapy.

Choice D: Capillary refill less than 3 seconds

Capillary refill time of less than 3 seconds suggests adequate perfusion, as normal is under 2 seconds. Dehydration may prolong this time, but “less than 3 seconds” could include slightly delayed values (e.g., 2.5 seconds). UpToDate and NIH studies (e.g., Doan et al., 2010) note it as useful but less specific than urine specific gravity for confirming ORT effectiveness.