PEDIATRIC SURGERY

Pediatric surgery is a specialized field of surgery for the treatment of conditions that can be surgically corrected in a baby, child, or adolescent. The purpose of pediatric surgery varies with the procedure. In general, the purpose is to surgically correct a congenital condition, disease, traumatic injury, or other disorder in the pediatric patient. Pediatric surgeons provide treatment for young patients— newborns up through late adolescence.

Pediatric surgery is the surgical branch that uses operative techniques to correct certain pediatric conditions (i.e., congenital abnormalities, tumors, chronic diseases, and traumatic injuries). There are different specialties within the field that include:
• pediatric general surgery
• pediatric otolaryngology (ear, nose, and throat)
• pediatric ophthalmology (eye)
• pediatric urology (urogenital system)
• pediatric orthopedic (bone) surgery
• pediatric neurological (brain and spinal cord) surgery
• pediatric plastic (reconstructive and cosmetic) surgery

The American Academy of Pediatrics has established specific guidelines for referral to subspecialists. The pediatric patient has special considerations that differentiate him or her, both physically and psychologically, from an adult. A neonate (newborn) poses great challenge in surgical treatment since the tiny structures and immature organ systems may not cope with disease-induced stress and the physical demands of a major operative procedure.

A newborn infant may still be developing key bodily functions, or may have special requirements. Key areas of concern in the newborn include:
• cardiovascular (heart) system
• thermoregulation (temperature requirements of 73°F [22.8°C])
• pulmonary (lung) function
• renal (kidney) function
• immature immunity and liver
• special requirements for fluid, electrolyte (necessary elements such as sodium, potassium, and calcium) and nutrition

The pediatric surgeon must take into account the special requirements unique to the young surgical patient. The pediatric surgeon is trained to treat the entire spectrum of surgical illnesses. The following is an overview (with symptoms) of the more common pediatric conditions that require surgery typically performed by the pediatric surgeon.

Alimentary tract obstruction Obstruction of the alimentary tract (tubes of digestion extending from the mouth to the anus) is characterized by four cardinal symptoms:
• abdominal distention (an abdomen that becomes large and appears swollen)
• bilious vomiting (due to bile in the stomach)
• maternal polyhydramnios (excess amniotic fluid in the amniotic sac, greater than 2,000 ml) before birth
• failure to pass meconium (dark green or black sticky excretion passed via the newborn’s rectum) in the first 24 hours of life

ESOPHAGEAL ATRESIA AND TRACHEOESOPHAGEAL FISTULA.
This is a congenital deformity of the esophagus (the tube that passes food from the mouth to the stomach). Symptoms include severe respiratory distress (the neonate cannot breathe) and excessive salivation. Other clinical signs include cyanosis (bluish discoloration of the skin due to oxygen deprivation), choking, and coughing.

PYLORIC ATRESIA AND RELATED CONDITIONS.
Pyloric atresia is a condition that occurs when the pyloric valve, located between the stomach and duodenum, fails to open. Food cannot pass out of the stomach, resulting in vomiting clear gastric juice at attempted feedings. Maternal polyhydramnios is present before birth in more than 60% of cases.

Other areas of the colon (duodenum, jejunum, ileum) can be obstructed during development, with symptoms present at birth. Most of these disorders share the four cardinal symptoms of alimentary obstruction.

INTUSSUSCEPTION.
Intussusception accounts for 50% of intestinal obstruction in patients who are three months to one year of age. Eighty percent of cases are observed by the child’s second birthday. The cause of intussusception is not known, and it is more common in males who are well nourished and apparently healthy. The symptoms include a sudden onset of abdominal pain characterized by episodic screaming and drawing up of the legs. In 60% of patients, vomiting and blood in the stool are common findings (either bright red or occult [hidden] blood).

Typically, the bowel movements look like currant jelly, consisting of mucus and blood mixed together. Currant jelly stool is the most common clinical observation for patients with intussusception. During physical examination, patients will exhibit abdominal distention, and in 65% of cases there is a sausage-shaped mass that can be felt in the upper right portion of the abdomen toward the mid-abdomen. Ultrasound studies are a reliable method of diagnosis.

FAILURE TO PASS MECONIUM.
Failure to pass meconium (meconium ileus) is associated with cystic fibrosis (a genetic disorder), colonic obstruction (colonic atresia), meconium plug syndrome, and aganglionic megacolon (also called Hirschsprung’s disease, a congenital absence of the nerves that provide gastrointestinal tract mobility).

Anorectal anomalies
There are many different types of anorectal anomalies common to male and female neonates, as well as deformities that are gender-specific since involvement of genitalia can occur. The surgery for these cases is complicated, and must be performed by an experienced pediatric surgeon. Complications of these procedures could result in permanent problems.

Necrotizing enterocolitis (NEC)
NEC affects 1–2% of patients admitted to a neonatal intensive care unit. It is a life-threatening illness characterized by abdominal distention, bilious vomiting, lethargy, fever, occult (not obvious) or gross (clearly seen) rectal bleeding. Additionally, affected patients may exhibit signs of hypothermia (temperature less than 96.5°F or 35.8°C), bradycardia (slow heart rate), abdominal mass (felt during palpation), oliguria, jaundice, and episodes of breathlessness (apnea). Survival of NEC surgery can be expected for 60–70% of patients.

Abdominal wall defects
Omphalocele is a defect that involves protrusion of abdominal contents into an external sac. This disorder occurs in one per 5,000 births. More than 50% of omphalocele patients have serious genetic deformities involving these body systems: cardiovascular (heart), musculoskeletal (muscle and bones), genitourinary (genital and bladder systems), and central nervous (brain and spinal cord). The overall survival rate for infants with omphalocele varies, and depends on defect size, other associated genetic abnormalities, and age of newborn. (Many infants with omphalocele are premature.) Approximately 33% of patients with omphaloceles do not survive.

GASTROSCHISIS
Gastroschisis is a defect in the abdominal wall to the side (lateral) of the umbilicus. It usually occurs to the right of an intact normal umbilical cord. The cause is unknown. The bowel protrudes to the outside of the abdomen during intrauterine life (while the embryo is developing inside the uterus). The amniotic fluid has an irritating effect on the exposed bowel, and causes infection of the bowels. The problem can be detected by ultrasound studies during pregnancy. Some pediatric surgeons and obstetricians recommend cesarean section (early elective delivery) to spare bowel trauma. The newborn patients typically require surgery, tube feedings for three to four weeks, and hospitalization for several weeks. The current survival rate for infants with gastroschisis is greater than 90%.