The nurse is caring for a 5-week-old infant presenting with a history of projectile vomiting after feedings. Which additional finding should the nurse expect to assess?

Projectile vomiting in a 5-week-old infant can be indicative of a condition known as pyloric stenosis. Pyloric stenosis is a narrowing of the pylorus, the opening from the stomach to the small intestine. It results in delayed gastric emptying, leading to the forceful, projectile vomiting observed after feedings. A. An olive-size mass in the epigastric area is a characteristic finding in infants with pyloric stenosis. The hypertrophied pyloric muscle feels like an olive and is often palpable in the upper abdomen. B. Stool that consists of mucus and blood is not a typical finding associated with pyloric stenosis. This symptom is more suggestive of gastrointestinal issues like infectious colitis or other conditions unrelated to pyloric stenosis. C. Rebound tenderness in the left lower abdominal quadrant is not a common finding in infants with pyloric stenosis. Rebound tenderness is typically associated with conditions like appendicitis in a different part of the abdomen. D. Frequent burping accompanied by poor feeding can be a sign of discomfort but is not a specific indicator of pyloric stenosis. Projectile vomiting is a more distinctive symptom associated with this condition.