A 1-month old infant is admitted to the emergency room with severe diarrhea. Which of the following assessments suggests the infant is severely dehydrated?

The infant weighs 10 pounds, which is equivalent to about 4.53692 kilograms (10 x 0.453592). The prescribed dose is 2 mg/kg, so the total dose per administration is 9.07384 mg (2 mg/kg x 4.53692 kg).

Since the elixir's strength is 15 mg/mL, we divide the total dose by the strength of the elixir to find out how many mL to administer: 9.07384 mg ÷ 15 mg/mL = 0.60492267 mL. Rounding to the nearest tenth, the nurse should administer 0.6 mL of ranitidine per dose to the infant.

A. Gastroesophageal reflux disease (GERD) is primarily treated with acid-reducing medications (like proton pump inhibitors) and lifestyle changes. Ondansetron is not indicated for GERD as it does not address the underlying acid reflux issues or symptoms related to that condition.
B. Paralytic ileus is a condition where there is a temporary cessation of bowel activity. While nausea and vomiting may occur as a symptom, ondansetron does not address the cause of ileus and may not be appropriate as a treatment option. Treatment typically focuses on resolving the underlying cause and may include bowel rest and monitoring.
C. Ondansetron is not typically used for diarrhea. Diarrhea management usually involves hydration and possibly medications like loperamide, depending on the cause. Ondansetron is not indicated for treating diarrhea as it primarily targets nausea and vomiting.
D. Ondansetron is specifically indicated for the prevention and treatment of nausea and vomiting, particularly those associated with chemotherapy, radiation therapy, or postoperative states. It works by blocking serotonin receptors in the brain that trigger the vomiting reflex.