Pediatric vomiting: Clinical

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Pediatric vomiting: Clinical

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A 4-week-old boy comes to the emergency department because of continuous postprandial non-bilious vomiting. He has continued to lose weight since birth and has become increasingly lethargic. The mother denies any complications with pregnancy or birth and denies any recent sick contacts. His temperature is 37.0°C (98.6°F), pulse is 130/min, respirations are 35/min, and blood pressure is 70/45 mm Hg. The child is lethargic with dry mucous membranes and a sunken anterior fontanelle. A palpable mass is felt in the epigastric region, and a succussion splash is heard on auscultation of the abdomen. Which of the following metabolic imbalances is most likely found in his laboratory results? 


Causes of vomiting vary a lot depending on the age group of the child, and usually it’s split into newborns or infants that are less than 3 months of age, infants that are over 3 months of age—or children—and adolescents.

First looking at newborns or young infants, less than 3 months of age, it may be very common to spit up a little bit of milk or formula, usually within the first hour after being fed. This is considered normal gastroesophageal reflux, or GER, and generally the vomiting is small-volume, non-projectile or not forceful, formula- or breast milk-colored, and the infant is looking healthy. It usually goes away on its own, but what can also help is feeding the baby in an upright position, burping it frequently during feeding breaks—meaning before switching breasts for breastfeeding moms and every 2 to 3 ounces for bottle-feeding moms—as well as after the baby is done eating, and avoiding active play right after feeds.

On the flip side, vomiting is considered pathologic when it occurs in large volumes, is projectile or has a green or bright yellow color given by bile, or when there are signs of illness, like fever, weight loss, or feeding refusal.

Pathologic vomiting can be caused by obstruction of the gastrointestinal tract. Now, if the obstruction is after the junction of the duodenum with the bile ducts at the ampulla of Vater, then the vomiting is bilious. This may be caused by intestinal malrotation with volvulus, atresia or stenosis of the lower duodenum or intestines, or by Hirschprung’s disease.

In intestinal malrotation with volvulus, there’s twisting of the mesentery around the superior mesenteric artery leading to intestinal obstruction, infarction, and necrosis.

This causes symptoms like acute, bilious vomiting, accompanied with abdominal distention and bloody diarrhea. In fact, bowel infarction can also damage the intestinal wall and allow the bacteria in the gut to move into the body, which can cause sepsis.


Pediatric vomiting refers to forcefully expelling stomach contents through the mouth in children. It might be an underlying sign of several conditions depending on a child's age.

In infants under 3 months, vomiting can be caused by conditions like intestinal malrotation with volvulus, duodenal atresia, hypertrophic pyloric stenosis, and annular pancreas. Above 3 months of age, vomiting is commonly seen in gastroenteritis, intussusception, and gastroparesis.

In adolescents, vomiting might be a sign of appendicitis, functional dyspepsia, and eating disorders like bulimia or anorexia nervosa. The treatment of pediatric vomiting depends on the underlying cause and may include drugs, fluids, hospitalization, or in some cases, surgery.


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