A 5.6 kg patient is receiving digoxin by mouth every 8 hours. The safe dose is 0.03-0.06 mg/kg/day. What is the maximum safe dose for this patient? (Round to the nearest hundredth.)

A. Croup is usually viral in origin (most commonly parainfluenza virus), so antibiotics are not indicated unless there is evidence of a secondary bacterial infection. Routine antibiotic administration does not improve viral croup and can contribute to antibiotic resistance.

B. Placing the child in a supine position may worsen airway obstruction and increase respiratory effort. Children with croup often assume an upright or sitting position to maximize airway patency and ease breathing.

C. Encouraging the child to lie down to conserve energy is not appropriate. Lying down can exacerbate airway obstruction in croup, increase stridor, and worsen respiratory distress.

D. Providing a cool mist humidifier or taking the child outside into cool night air helps reduce airway inflammation and swelling in the upper airway. Cool air can soothe the larynx, decrease stridor, and ease the barking cough. These noninvasive measures are first-line interventions to manage mild to moderate croup and prevent progression to severe respiratory distress. Supporting the child in an upright, calm position while monitoring oxygenation and respiratory effort is also essential.

A. Pancreatic enzyme replacement therapy (PERT) is not tied to the development of diabetes. While CF-related diabetes can occur due to progressive pancreatic damage, enzyme therapy is required much earlier to address malabsorption caused by blocked pancreatic ducts. Waiting for diabetes to develop would allow continued nutrient deficiencies, poor weight gain, and fat-soluble vitamin deficiencies (A, D, E, K).

B. Children with CF do not digest fats more efficiently than carbohydrates. In fact, fat digestion is particularly impaired because pancreatic lipase is insufficient due to duct obstruction. Proteins and carbohydrates are also affected to a lesser extent. PERT provides a mix of lipase, amylase, and protease to compensate for this deficiency and ensure adequate nutrient absorption.

C. CF does not cause an overproduction of digestive enzymes. On the contrary, thick mucus blocks pancreatic ducts, preventing enzymes from reaching the intestines. This blockage leads to enzyme deficiency in the gastrointestinal tract, resulting in malabsorption, steatorrhea (fatty stools), abdominal bloating, and poor growth.

D. In CF, mutations in the CFTR gene lead to thick, sticky mucus production in multiple organs, including the pancreas. This mucus obstructs the pancreatic ducts, preventing digestive enzymes such as lipase, amylase, and protease from reaching the small intestine. Without these enzymes, fats, proteins, and carbohydrates are incompletely digested, causing nutrient malabsorption, fatty stools, and poor weight gain. PERT replaces the missing enzymes, allowing proper digestion and absorption of nutrients, improving growth, and reducing gastrointestinal symptoms. Regular dosing with meals and snacks is essential to optimize nutrient absorption and support normal growth and development in children with CF.