Inspect the abdomen with the infant lying supine, optimally while asleep. The abdomen is protuberant due to poorly developed abdominal musculature. You will easily notice abdominal wall blood vessels and intestinal peristalsis.
Inspect the newborn's umbilical cord to detect abnormalities. Normally, there are two thick-walled umbilical arteries and one larger but thin-walled umbilical vein, which is usually located at the 12 o'clock position.
The umbilicus in the newborn may have a long cutaneous portion (umbilicus cutis), which is covered with skin, or an amniotic portion (umbilicus am-nioticus), which is covered by a firm gelatinous substance. The amniotic portion dries up and falls off within 2 weeks, while the cutaneous portion retracts to be flush with the abdominal wall.
A single umbilical artery may be associated with congenital anomalies, but also occurs in normal infants as an isolated anomaly.
An umbilical granuloma at the base of the navel is the development of pink granulation tissue formed during the healing process.
Inspect the area around the umbilicus for redness or swelling. Umbilical hernias are detectable at a few weeks of age.
A diastasis recti may be noted in normal infants. This involves separation of the two rectus abdominis muscles, causing a midline ridge, most apparent on contraction of the abdominal muscles. A benign condition in most cases, it resolves during early childhood. Chronic abdominal distention may also predispose to this condition.
You can percuss an infant's abdomen as you would for an adult, but be prepared to note greater tympanitic sounds due to the infant's propensity to swallow air. Percussion is useful for determining the size of organs and abdominal masses.
Umbilical hernias in infants are due to a defect in the abdominal wall, and can be up to 6 cm in diameter and quite protuberant when intraabdominal pressure is increased. Most disappear by 1 year, nearly all by 5 years.
An increase in pitch or frequency of bowel sounds is heard with gastroenteritis or, rarely, with intestinal obstruction.
A silent, tympanic, distended abdomen suggests peritonitis.
You will find it easy to palpate an infant's abdomen because he likes being touched. A useful technique to relax the infant, shown here, is to hold the legs flexed at the knees and hips with one hand and palpate the abdomen with the other. You may also want to use a pacifier or bottle to quiet the infant in this position.
Start gently palpating the liver of infants low in the abdomen, moving upwards with your fingers. This technique helps you avoid missing an extremely enlarged liver that extends down into the pelvis. With a careful examination, you can feel the liver edge in most infants, 1 to 2 cm below the right costal margin.
An enlarged, tender liver may be due to congestive heart failure or to storage diseases.
Similarly, you can usually palpate the spleen tip. In fact, you may be able to palpate the kidneys of infants by carefully placing the fingers of one hand in front of and those of the other behind each kidney. The descending colon is a sausagelike mass in the left lower quadrant.
Once you have identified the normal structures in the infant's abdomen, use palpation to identify abnormal masses.
Abnormal abdominal masses in infants can be associated with the kidney (e.g., hydronephrosis), bladder (e.g., urethral obstruction), bowel (e.g., Hirschsprung's disease, or intussusception), and tumors.
In pyloric stenosis, deep palpation in the right upper quadrant or midline can reveal an "olive," or a 2-cm firm pyloric mass. While feeding, some infants with this condition will have visible peristaltic waves pass across their abdomen, followed by projectile vomiting.
Was this article helpful?