PEDIATRIC SURGERY UPDATE ©
VOLUME 04, 1995

VOL 04 NO 01 JANUARY 1995

TFS

Testicular feminization syndrome (TFS) is a genetic form of male pseudohermaphroditism (patient who is genetically 46 XY but has deficient masculinization of external genitalia) caused by complete or partial resistance of end organs to the peripheral effects of androgens. This androgenic insensitivity is caused by a mutation of the gene for androgenic receptor inherited as an X-linked recessive trait. In the complete form the external genitalia appear to be female with a rudimentary vagina, absent uterus and ovaries. The infant may present with inguinal hernias that at surgery may contain testes. Axillary/pubic hair is sparse and primary amenorrhea is present. The incomplete form may represent undervirilized infertile men. Evaluation should include: karyotype, hormonal assays, pelvic ultrasound, urethrovaginogram, gonadal biopsy and labial skin bx for androgen receptor assay. This patients will never menstruate or bear children. Malignant degeneration (germ cell tumors) of the gonads is increased (22-33%). Early gonadectomy is advised to: decrease the possible development of malignancy, avoid the latter psychological trauma to the older child, and eliminate risk of losing the pt during follow-up. Vaginal reconstruction is planned when the patient wishes to be sexually active.

NEC and PPD

Complicated Necrotizing Enterocolitis (NEC) is the most common neonatal surgical emergency of modern times, has diverse etiologies, significant mortality and affects mostly premature babies. The use of primary peritoneal drain (PPD) in the management of NEC dates from 1977. The technique is used in the very low birth weight premature infant (<1500 gm) with pneumoperitoneum, metabolic and hemodynamic instability. Consist of a right lower quadrant incision and placement of a drainage (penrose or catheter) under local anesthesia with subsequent irrigation performed bedside at the NICU. Initially used as a temporizing measure before formal laparotomy, some patient went to improvement without the need for further surgery(almost one-third). They either had an immature (fetal type) healing process or a focal perforation (not associated to NEC?) which healed spontaneously. Those babies not improved by PPD either die (20%), go on to laparotomy and half die (20%) or develop complications (24%). Some suggestion made are: PPD should be an adjunct to preop stabilization, before placing drain be sure pt has NEC by X-rays, persistent metabolic acidosis means uncontrolled peritoneal sepsis, do not place drain in pts with inflammatory mass or rapid development of intraperitoneal fluid, the longer the drainage the higher the need for laparotomy.

Pancreatic Pseudocysts

Pancreatic pseudocyst formation is an uncommon complication of pancreatic inflammatory disease (pancreatitis) or trauma in children. More than half cases are caused by blunt abdominal trauma. Ultrasound is the most effective and non-invasive way of diagnosing pancreatic pseudocysts. Acute pseudocysts are managed expectantly for 4-6 wk. until spontaneous resolution occurs. 25-50% will undergo spontaneous resolution. Medical therapy consists of decreasing pancreatic stimulation and giving nutritional support. Rupture is the major complication of conservative management. Chronic pseudocysts (> three mo.) will benefit from prompt operation and internal drainage since resolution is rare. Percutaneous catheter drainage under local anesthesia using Ultrasound or CT guided technique is an appropriate method of first-line therapy for non-resolving (chronic) or enlarging pancreatic pseudocysts. The approach is transgastric or transcutaneous. Those cysts that fail to resolve with percutaneous drainage should go investigation of ductal anatomy to rule out disruption of the main pancreatic duct. The need for further surgery (drainage or resectional) will depend on the status of the duct of Wirsung.

VOL 04 NO 02 FEBRUARY 1995

Wound Infections

A surgical wound is considered infected if it develops pus four weeks after its creation. Wounds that heal by primary intention are not infected. Cellulitis of the suture line, subcutaneous seroma formation, and simple stitch abscess can be considered probable infected wounds. Factors associated to wound infections are: (1) degree of microbial contamination during the initial procedure, (2) resistance of the host (depends on age, primary medical condition, state of nutrition and immunological system), (3) initial condition of the wound (clean, contaminated or dirty). Prophylaxis to reduce the incidence of wound infection should consider that the host may have a series of medical conditions that predispose him to wound infection such as primary (B-Cell, T-Cell, complement) or secondary (sepsis, trauma, shock, chemotherapy, radiation) immunological deficiencies along with a poor nutritional status. Bacterial contamination during gastrointestinal procedures should be reduced using: mechanical cleansing of the bowel (golytely), oral and systemic antibiotics, and adequate skin preparation. Other factors that could have an impact on wound infections are keeping hemostasis, manage tissue gently, avoid dead spaces and irrigate contaminated wounds with saline (mechanical cleansing). Infected wounds can either show an early (less than 48 hours) or late (after 60 hours) clinical presentation. This may consist of unduly pain, fever, edema, cellulitis, fever and leucocytosis. Early wound infections are associated to gram positive organism with dramatic (gangrenous) presentation that will need early debridement, constant surveillance, and parenteral antibiotics. Late wound infections are caused by gram positive, negative or polymicrobial flora with a localizing nature. They generally yield to drainage and local measures.

Manometry in IA

Repaired cases of Imperforate Anus (IA) are evaluated clinically, manometrically and radiographically. Manometry will measure the anorectal pressure profile (APP) and recto-anal inhibitory reflex (RAI). The APP permit to determine the length of the closing mechanism and pressure height of the anorectal muscles, and RAI detects the presence of relaxation of the anal canal upon distension of the rectal ampulla. Continent patient after repaired IA may show: marked high pressure zone, adequate length/pressure height of neo-anal canal, normal anorectal pressure difference, and positive RAI reflex. Incontinent children may show: no marked high pressure zone, decrease anal resting pressure, decrease anorectal pressure difference and absent RAI reflex. Causes of incontinence in these patients are: muscular deficiency (short sphincter complex), deficient motor/sensory innervation (not aware, no urge), mental retardation, not yet toilet trained, and chronic constipation (motility problems). Poor results after anorectal surgery are associated to: high anorectal defect (recto-vesical in males, cloaca in females), absent sacral segments, associated neurologic malformations, and poorly developed striated muscle complex.

Esophageal Diverticulum

This is an extremely rare condition with a congenital or acquired etiology. Most are found in the mid-esophageal area. Initial symptoms are those of dysphagia and regurgitation. Esophagogram is diagnostic and endoscopy corroborates its nature. It seems that the submucosa protrudes through the circular esophageal muscle layer carrying muscularis mucosa without significant evidence of inflammatory changes. Some cases are associated to a motor disturbances of the esophagus. Patients may be at risk of developing an esophago-bronchial fistula to the main bronchus during adult life. Acquired cases are associated to the use of myotomy procedures to lengthened the proximal esophageal pouch of esophageal atresia patients. Surgical resection for symptomatic cases is curative.

VOL 04 NO 03 MARCH 1995

Choledochal Cyst

Choledochal cyst is a rare dilatation of the common bile duct, prevalent in oriental patients (Japan). More than 60% of patients are less than 10 years old. The etiology is related to an abnormal pancreatic-biliary junction (common channel theory) causing reflux of pancreatic enzymes into the common bile duct (trypsin and amylase). Symptoms are: abdominal pain, obstructive jaundice, a palpable abdominal mass, cholangitis, and pancreatitis. Infants develop jaundice more frequently, causing diagnostic problems with Biliary Atresia. Older children may show abdominal pain and mass. Jaundice is less severe and intermittent. Diagnosis is confirmed with Ultrasound and corroborated with a HIDA (or DISIDA) Scan. Choledochal cysts are classified depending on morphology and localization. Management is surgical and consist of cyst excision and roux-en-Y hepatico-jejunostomy reconstruction. Cyst retention penalties paid are: recurrent cholangitis, stone formation, pancreatitis, biliary cirrhosis, and malignancy. Long-term follow-up after surgery is advised.

Testicular Teratoma

Testicular neoplasm in children is rare. Yolk sac tumors are the most frequent one followed by teratomas that are usually benign tumors of non-germinal origin. Testicular teratomas (TT) present during infancy as unilateral testicular masses. Due to the characteristic at palpation and its eventual transillumination they can be confused with hydroceles. TT display mature, immature or malignant histopathological characteristics. Most are mature (cystic variety) with survival above 95%. Scrotal sonography constitutes the main diagnostic investigation: findings most commonly reveal a predominantly cystic lesion with echogenic component along its wall. Other times a complex mass occupying most of the testes with areas of calcification and cyst formation. Preop diagnosis is possible if characteristic features are recognized. Orchiectomy is adequate therapy for mature and immature testicular teratomas. Although transcrotal orchiectomy is not an appropriate surgical procedure and testicular biopsy is detrimental to prognosis in most testicular tumors, sparing enucleation (tumorectomy) based on their benign nature (proven by instant frozen section) and absent intratubular germ cell neoplastic characteristics can be performed in some well delineated and superficial tumors. Malignant tumors should be managed by orchiectomy, high spermatic cord ligation, multiagent chemotx, and at times radiotx. TT tumor markers are: alpha fetoprotein (AFP) and human chorionic gonadotropin (HCG). Postop rise in AFP levels is a good indicator of malignant recurrence.

Splenoptosis

Splenoptosis (Wandering spleen) is a rare congenital fusion anomaly of the dorsal mesogastrium of the spleen that results in failure and laxity of its normal attachment to the diaphragm, retroperitoneum and colon. Relatively more common in children than adults, and females outnumber males. The child presents with an asymptomatic mass (splenomegaly), mass and subacute gastrointestinal complaints or with acute abdominal symptoms. These are the result of torsion of the pedicle, ischemia and splenic sequestration. 50% of spleens are lost to acute ischemia from torsion. Other complications are: pancreatitis, hypersplenism and cyst formation. Lab tests are nonspecific, but may occasionally reveal evidence of hypersplenism or functional asplenia. Diagnosis needs a high index of suspicion, and is achieved with: Ultrasound, CT, and Scintigram. Management consists of splenectomy for frank splenic infarct, or splenopexy for viable organs. Splenopexy is achieved by creating an extraperitoneal pocket or wrapping the spleen in absorbable mesh and anchoring to the retroperitoneum (splenic nood).

VOL 04 NO 04 APRIL 1995

Mesenteric Cysts

Cystic lesions of the mesentery are rare. One-third of patients with these lesions are children with approximately 700 cases reported in the world literature. Mesenteric cysts can be either cystic lymphangiomas or mesotheliomas. They are commonly found in the small bowel mesentery (2/3), followed by the mesocolon (1/3). Most are multilocular varying in size from 3 to 25 cm. In children cystic lymphangioma is the predominant mesenteric lesion. Lymphangioma is a more invasive and larger lesion that sometimes requires concomitant bowel resection. They are lined with endothelium, containing smooth muscle fiber or lymphoid tissue. Mesotheliomas are simple mesothelial cell layer cysts amenable to excision. Clinical presentation is either abdominal pain (crampy in nature), a growing mass, acute bowel obstruction, or hemorrhage into the cyst. US is the initial imaging modality to evaluate a child with this presentation. CT Scan can show extent of cyst involvement. Management consists of resection or marsupialization. Long-term follow-up is advised due to the possibility of recurrence.

Laparoscopic Cholecystectomy

Laparoscopic Cholecystectomy (LC) has become the procedure of choice for the removal of the disease gallbladder of children. The benefit of this procedure in children is obvious: is safe, effective, well tolerated, it produces a short hospital stay, early return to activity and reduced hospital bill. Several technical differences between the pediatric and adult patient are: lower intrabdominal insufflation pressure, smaller trocar size and more lateral position of placement. Complications are related to the initial trocar entrance as vascular and bowel injury, and those related to the procedure itself; bile duct injury or leak. Three 5 mm ports and one 10 mm umbilical port is used. Pneumoperitoneum is obtained with Veress needle insufflation or using direct insertion of blunt trocar and cannula. Cholangiography before any dissection of the triangle of Calot using a Kumar clamp is advised by some workers to avoid iatrogenic common bile duct injuries during dissection due to anomalous anatomy, it also remains the best method to detect common bile ducts stones. Treatment may consist of: (1) endoscopic sphincterotomy, (2) opened or laparoscopic choledochotomy, or (3) transcystic choledochoscopy and stone extraction. Children with hemolytic disorders, i.e. Sickle cell disease, have a high incidence of cholelithiasis and benefit from LC with a shorter length of postop stay and reduced morbidity.

Hemangiopericytoma

This rare vascular tumor first described in 1942 arises from the contractile cells normally found around capillaries and venules known as pericytes. Roughly 1% of them are found in children. In infants it has a different gross, histologic and biologic behavior recognize as congenital or infantile hemangiopericytoma. The congenital variant is most commonly found in the subcutaneous tissue, head and neck, the extremity and trunk. The tumor is multilobulated, partially encapsulated, soft, spongy, and hypervascular. Usually a solitary and non-tender mass. Microscopy shows branching vascular spaces lined by normal endothelium and elongated, irregular pericytes. Focal necrosis, calcifications and mitotic activity may be found. An assessment of cytologic atypia and mitotic activity is crucial in the anticipation of indolent or aggressive behavior. The uniform behavior of the tumor is benign, but a few cases of recurrence, or even metastatic spread have been reported in infants. Criteria for malignancy are rapid growth of the primary lesion, the appearance of metastatic lesion in subcutaneous tissue or lung, increased mitotic rate, greater cellularity and pleomorphism. The treatment of choice is complete excision with a margin of normal tissue if possible. Spontaneous regression of the remnant tumor has been reported. Longterm follow-up is essential for early detection of metastatic disease.

VOL 04 NO 05 MAY 1995

Laparoscopic Appendectomy

Semm, a gynecologist, is credited with inventing Laparoscopic Appendectomy (LA) in 1982. With the arrival of video-endoscopic procedures the role of LA in the management of acute appendicitis in children has been studied and compared with the conventional open appendectomy (OA). General advantages of LA identified are: ease and rapid localization of the appendix, ability to explore and lavage the entire abdominal cavity, less cutaneous scarring, more pleasing cosmetically, and a rapid return of intestinal function and full activity. Disadvantages are: expensive instrumentation, time-consuming and tedious credentialing, and the major benefit is in the postop period. Analyzing the results of several series that compare LA vs. OA in the management of acute appendicitis we can conclude that LA: produces no difference with OA in respect to OR complications and postop morbidity, has a longer operating and anesthesia time, higher hospital costs, a shorter length of stay, less postop pain, less pain medication requirement, and shorter convalescence. One series warned that complicated cases of appendicitis done by LA could increase the postop infectious rate requiring readmission. Otherwise, they all favored LA in the management of appendicitis. Still, unresolved issues in my mind are: Does LA reduces postop adhesions?, Is it necessary to remove a normal looking appendix during a negative diagnostic laparoscopy performed for acute abdominal pain?, Will the increase intrabdominal pressure alters the diaphragmatic lymphatic translocation of bacteria favoring higher septic rates in complicated cases?

Pyocele

Infected hydroceles (pyoceles) are extremely rare in infants and children, but they should always be included in the differential diagnosis of a tender suspicious testicular mass. Thought to be caused by intraperitoneal infection (perforated appendicitis) that extends into the scrotum through a patent processus vaginalis, the few reported cases in the literature has no intra-abdominal cause (idiopathic) and the most plausible explanation is hematogenous route of infection. Testicular scan will show adequate vascular flow and Ultrasound Doppler investigation will show a complex mass with internal echoes separated from the testis (paratesticular) suggesting a tumor at times. Management consist of exploration of the scrotum through an inguinal approach, evacuation of the hydrocele, high ligation, and culture routine. Patient is placed on antibiotherapy during the postop period.

CDH- Delayed Presentation

Congenital Diaphragmatic Hernia (CDH) associated with pulmonary hypoplasia is a common cause of severe respiratory distress in the newborn. Delayed presentation beyond the neonatal period is rare, estimated to occur in 4-6% of cases. Infants and children will present with either respiratory or gastrointestinal symptoms such as: chronic respiratory tract infection, vomiting, intermittent intestinal obstruction, and feeding difficulty. Occasionally the child is asymptomatic. The small size of the defect protected by either the spleen or the liver and the presence of a hernial sac may delay the intestinal herniation into the chest. A rise intrabdominal pressure by coughing or vomiting transmitted to any defect of the diaphragm makes visceral herniation more likely. Diagnosis is confirmed by chest or gastrointestinal contrast imaging. Management consists of immediate surgery after preop stabilization. Most defects can be closed primarily through an abdominal approach. Chest-tube placement in the non-hypoplastic lung is of help. Surgical results are generally excellent. A few deaths have resulted from cardiovascular and respiratory compromise due to visceral herniation causing mediastinal and pulmonary compression.

VOL 04 NO 06 JUNE 1995

Congenital Torticollis

Congenital muscular torticollis is a disorder characterize by shortening of the cervical muscles, most commonly the sternocleidomastoid (SCM) muscle, and tilting of the head to the opposite side. This is the result of endomysial fibrosis of the SCM muscle. There is a relationship between birth position and the side affected by the contracture. Congenital torticollis causes: plagiocephaly (a craniofacial deformity), fascial asymmetry (hemihypoplasia), scoliosis and atrophy of the ipsilateral trapezius muscle if not corrected. Torticollis can develop at any age, although is more common during the first six months of life. The SCM muscle can be a fibrous mass, or a palpable tumor 1-3 cm in diameter within the substance of the muscle is identified by two to three weeks of age. Management is conservative in most cases using early physiotherapy exercises' a mean duration of three months to achieve full passive neck range of motion. The severity of restriction of motion is the strongest predictor of treatment duration. Those children with failed medical therapy or the development of fascial hemihypoplasia should undergo surgical transection of the SCM muscle.

TDC

Thyroglossal duct cyst (TDC) is the most common congenital anterior midline neck mass usually (2/3 of cases) presenting before the second decade of life. Symptoms appear at an average age of four with the sudden appearance of a cystic mass at the angle of neck level moving with tongue protrusion and swallowing. Males are more commonly affected than females. TDC is an embryologic anomaly arising from epithelial remnant left after descent of the developing thyroid from the foramen cecum. The lining is cuboidal, columnar or pseudostratified epithelium. TDC is associated to discomfort, infection and a slight probability of malignancy. A legally protective requirement is to document that the mass is not ectopic thyroid gland. Diagnosis is physical. Sonograms will show a cyst between 0.4 and 4 cm in diameter, with variable sonographic appearance and no correlation with pathological findings of infection or inflammation. Once infected surgical excision is more difficult and recurrence will increase. Management is Sistrunk's operation: Excision of cyst with resection of duct along with the central portion of hyoid bone (a minimum of 10-15 mm of hyoid bone should be removed) and some muscle surrounding the proximal ductules (the length of single duct above the hyoid bone spreads into many ductuli as it approach the foramen cecum). Extensive dissection can cause pharyngodynia. The greatest opportunity for cure is surgery at initial noninflamed presentation. Inadequate excision is a risk factor for further recurrence.

BCF

Branchial cleft fistulas (BCF) originate from the 1st to 3rd branchial apparatus during embryogenesis of the head and neck. Anomalies of the 2nd branchial cleft are by far the most commonly found. They can be a cyst, a sinus tract or fistulas. Fistulas (or sinus tract if they end blindly) display themselves as small cutaneous opening along the anterior lower third border of the sternocleidomastoid muscle, communicates proximally with the tonsillar fossae, and can drain saliva or a mucoid secretion. Management consists of excision since inefficient drainage may lead to infection. I have found that dissection along the tract (up to the tonsillar fossa!) can be safely and easily accomplished after probing the tract with a small guide wire in-place. This will prevent injury to nerves, vessels and accomplish a pleasantly smaller scar. Occasionally a second stepladder incision in the neck will be required. 1st BCF are uncommon, located at the angle of the mandible, and communicating with the external auditory canal. They have a close association with the fascial nerve. 3rd BCF are very rare, run into the piriform sinus and may be a cause of acute thyroiditis or recurrent neck infections.References