Pediatric Hernias

Approximately 400 years ago, a French surgeon named Ambroise Pare described the reduction of an incarcerated pediatric hernia and the application of trusses. He recognized that inguinal hernias in children were probably congenital in nature and that they could be cured. Unfortunately, despite the many historical descriptions of conservative medical management of inguinal hernias, no effective nonsurgical means of treating this condition is recognized. All pediatric inguinal hernias require operative treatment to prevent the development of complications, such as inguinal hernia incarceration or strangulation.

Today, inguinal hernia repair is one of the most common pediatric operations performed. Inguinal hernia is a type of ventral hernia that occurs when an intra-abdominal structure, such as bowel or omentum, protrudes through a defect in the abdominal wall. Most hernias that are present at birth or in childhood are indirect inguinal hernias. Other less common types of ventral hernias include umbilical, epigastric, and incisional hernias.

In this article, the embryology, clinical presentation, and management of inguinal hernias are discussed in relation to the pediatric population. Because inguinal hernias are common, every clinician must be well versed in the subject and able to provide optimal care to patients and their families, especially because hernias can be organ-threatening or life-threatening if not expeditiously managed. Examples of hernias are shown in the images below.

Typical appearance of an infant with a large right indirect inguinal hernia. The right scrotal sac is enlarged and contains palpable loops of bowel and fluid.

A premature baby boy with bilateral giant inguinoscrotal hernias. Because of the large size of the hernias, operative repair typically requires repair of the inguinal floor in addition to the high ligation of the indirect hernia sac.

The processus vaginalis is an outpouching of peritoneum attached to the testicle that trails behind as it descends retroperitoneally into the scrotum. When obliteration of the processus vaginalis fails to occur, inguinal hernia results.[1] A review of embryonic development of the inguinal region is important to understanding the pathophysiology and surgical management of inguinal hernias.

Although the sex of the embryo is determined at fertilization, the gonads do not begin to differentiate until 7 weeks' gestation. Primordial germ cells migrate along the dorsal mesentery of the gut. They arrive at the primitive gonads early in the fifth week of development and, during the sixth week, invade the genital ridges, which lie on the medial aspect of the mesonephros. The coelomic epithelium proliferates, and the underlying mesenchyme condenses, forming the primitive sex cords.

Under the influence of the Y chromosome, the cords in the male embryo proliferate to form the testes. Near the end of the second month, the testis and mesonephros are attached by the urogenital mesentery to the posterior abdominal wall. As the mesonephros degenerates, only the testis remains suspended. At its caudal end, the attachment is ligamentous and is known as the caudal genital ligament. The gubernaculum, a mesenchymal structure rich in extracellular matrices, also extends from the caudal pole of the testis. This structure attaches in the inguinal region between the differentiating internal and external oblique muscles prior to descent of the testes. As the testes begin to descend at about 28 weeks' gestation, an outgrowth of gubernaculum from the inguinal region grows toward the scrotal area, and as the testis passes through the inguinal canal, this portion of the gubernaculum comes in contact with the scrotal floor.

During this time, the peritoneum of the coelomic cavity is forming an evagination on each side of the midline into the ventral abdominal wall. This evagination, known as the processus vaginalis, follows the path of the gubernaculum testis into the scrotal swellings and forms, along with the muscle and fascia, the inguinal canal. The descent of the testes through the inguinal canal is thought to be regulated by both androgenic hormones produced by the fetal testis and mechanical factors resulting from increased abdominal pressure.

As each testis descends, the layers of the abdominal wall contribute to the layers of the spermatic cord. The internal spermatic fascia is a reflection of the transversalis fascia, the internal oblique muscle helps form the cremaster muscle, and the external spermatic fascia results from the external oblique aponeurosis. In addition, a reflected fold of the processus vaginalis covers each testis and becomes known as the visceral and parietal layers of the tunica vaginalis.

In the female embryo, the ovaries descend into the pelvis but do not leave the abdominal cavity. The upper portion of the gubernaculum becomes the ovarian ligament, and the lower portion becomes the round ligament, which travels through the inguinal ring into the labium majus. If the processus vaginalis remains patent, it extends into the labium majus and is known as the canal of Nuck.

Before birth, the layers of the processus vaginalis normally fuse, closing off the entrance into the inguinal canal from the abdominal cavity. In some individuals, the processus vaginalis remains patent through infancy, into childhood, and possibly even into adulthood. The precise cause of the obliteration of the processus vaginalis is unknown, but some studies indicate that calcitonin gene-related peptide (CGRP), released from the genitofemoral nerve, may have a role in the fusion.

When luminal obliteration fails to occur, a ready-made sac is present where abdominal contents may herniate. Even when the processus vaginalis is patent, the entrance may be adequately covered by the internal oblique and transverse abdominal muscles, preventing escape of abdominal contents for many years. Failure of fusion can result not only in an inguinal hernia, but also in a communicating or noncommunicating hydrocele.

In infants, the most common type of hydrocele is the communicating type. A communicating hydrocele results when the proximal portion of the processus vaginalis remains patent, allowing fluid from the abdominal cavity to freely enter the scrotal sac. When closure is present proximally but fluid remains trapped within the tunica distally, a noncommunicating hydrocele results.

Frequency

United States

Although the exact incidence of indirect inguinal hernia in infants and children is unknown, the reported incidence ranges from 1-5%. Sixty percent of hernias occur on the right side. Premature infants are at increased risk for inguinal hernia, with incidence rates of 2% in females and 7-30% in males. Approximately 5% of all males develop a hernia during their lifetime.

A study that evaluated the incidence of inguinal hernia in almost 80,000 children found that the cumulative incidence of inguinal hernia from birth to 15 years of age was 6.62% in males and 0.74% in females.[2]

International

International incidence rates are similar to those in the United States.

Mortality/Morbidity

An incarcerated or strangulated inguinal hernia can result in severe complications and even death. An incarcerated or strangulated inguinal and/or femoral hernia may also result in significant sequela, depending on which visceral structure is involved in the hernia sac. Such sequela can range from life-threatening complications to gonadal dysfunction, including intestinal necrosis and perforation, intestinal obstruction, intestinal stricture, testicular necrosis, testicular atrophy, ovarian necrosis, ovarian atrophy, and tubal stricture.

Race

Inguinal hernia appears to occur equally among races. Umbilical hernias, on the other hand, appear to be more common in blacks than in other races.

Sex

Inguinal hernias are much more common in males than in females. The male-to-female ratio is estimated to be 4-8:1.

Age

Premature infants are at an increased risk for inguinal hernia, with the incidence ranging from 7-30%. Moreover, the associated risk of incarceration is more than 60% in this population. Most pediatric ventral and inguinal hernias are detected in the first year of life. Occasionally, hernias may remain asymptomatic and unnoticed by the parents until later in life. Finding an adult patient with an indirect inguinal hernia that has been present since birth is not unusual.

See the list below:

• The infant or child with an inguinal hernia generally presents with an obvious bulge at the internal or external ring or within the scrotum. The parents typically provide the history of a visible swelling or bulge, commonly intermittent, in the inguinoscrotal region in boys and inguinolabial region in girls. The image below depicts a 4-month-old baby boy with a large right-sided inguinal hernia.

  Typical appearance of an infant with a large right indirect inguinal hernia. The right scrotal sac is enlarged and contains palpable loops of bowel and fluid.

• The swelling may or may not be associated with any pain or discomfort. More commonly, no pain is associated with a simple inguinal hernia in an infant. The parents may perceive the bulge as being painful when, in truth, it causes no discomfort to the patient.

• The bulge commonly occurs after crying or straining and often resolves during the night while the baby is sleeping.

• Indirect hernias are more common on the right side because of delayed descent of the right testicle. Hernias are present on the right side in 60% of patients, on the left in 30%, and bilaterally in 10% of patients.

• If the patient or the family provides a history of a painful bulge in the inguinal region, one must suspect the presence of an incarcerated inguinal hernia. Patients with an incarcerated hernia generally present with a tender firm mass in the inguinal canal or scrotum. The child may be fussy, unwilling to feed, and inconsolably crying. The skin overlying the bulge may be edematous, erythematous, and discolored.

Examine the patient in both supine and standing positions. Physical examination of a child with an inguinal hernia typically reveals a palpable smooth mass originating from the external ring lateral to the pubic tubercle. The mass may only be noticeable after coughing or performing a Valsalva maneuver, and it should be reduced easily. Occasionally, the examining physician may feel the loops of intestine within the hernia sac. In girls, feeling the ovary in the hernia sac is not unusual; it is not infrequently confused with a lymph node in the groin region. In boys, palpation of both testicles is important to rule out an undescended or retractile testicle.

• Inguinal hernia incarceration: The bowel can become swollen, edematous, engorged, and trapped outside of the abdominal cavity, a process known as incarceration. Incarceration is the most common cause of bowel obstruction in infants and children and the second most common cause of intestinal obstruction in North America (second only to intra-abdominal adhesions from previous surgeries). If entrapment becomes so severe that the vascular supply is compromised, inguinal hernia strangulation results. In cases of incarceration, ischemic necrosis develops, and intestinal perforation may result, representing a true medical emergency. When an incarceration is encountered, an attempt should be made to reduce it manually if the patient has no signs of systemic toxicity (eg, leukocytosis, severe tachycardia, abdominal distention, bilious vomiting, discoloration of the entrapped viscera). If the patient appears toxic, emergent surgical exploration after appropriate resuscitation is necessary.

• Hernia and hydrocele: In boys, differentiating between a hernia and a hydrocele is not always easy. Transillumination has been advocated as a means of distinguishing between the presence of a sac filled with fluid in the scrotum (hydrocele) and the presence of bowel in the scrotal sac. However, in cases of inguinal hernia incarceration, transillumination may not be beneficial because any viscera that is distended and fluid-filled in the scrotum of a young infant may also transilluminate. A rectal examination may be helpful if intestine can be felt descending through the internal ring.

• Silk sign: When the hernia sac is palpated over the cord structures, the sensation may be similar to that of rubbing 2 layers of silk together. This finding is known as the silk sign and is highly suggestive of an inguinal hernia. The silk sign is particularly important in young children and infants, in whom palpation of the external inguinal ring and inguinal canal is difficult because the patients' small size.

• Spontaneously reducing hernia: Inguinal hernias that spontaneously reduce (ie, they are only noticed by the parents or caregivers and elude the examining physician) are not unusual. In such cases, maneuvers to increase the patient's intra-abdominal pressure may be attempted. Lifting the infant's or the child's arms above the head may provoke crying or a struggle to get free and thus increased intra-abdominal pressure. Older children can be asked to cough or blow up a balloon.

• Femoral hernia: A femoral hernia can be very difficult to differentiate from an indirect inguinal hernia. Its location is below the inguinal canal, through the femoral canal. The differentiation is often made only at the time of operative repair, once the anatomy and relationship to the inguinal ligament is clearly visualized. The signs and symptoms for femoral hernias are essentially the same as those described for indirect inguinal hernias.

The cause of inguinal hernia in children can be termed an abnormality of embryologic development of the fetus. However, some children may present with an acquired form of inguinal hernia, also called a direct inguinal hernia. In this type of hernia, weakness of the inguinal floor is present, which allows for protrusion of viscera from the abdominal cavity. The hernia sac is composed of the peritoneal fold that contains the hernia.

Anatomically speaking, indirect and direct inguinal hernias differ in that the direct hernia bulges through the inguinal floor medial to the inferior epigastric vessels and the indirect hernia arises lateral to the inferior epigastric vessels. Either hernia may cause fullness or a palpable bulge in the inguinal region, and distinguishing between the two types on the basis of physical examination findings may be difficult. The clinician may assume, until proven otherwise, that the pediatric patient with an inguinal hernia has indirect inguinal hernia.

• The following are associated with an increased risk of inguinal hernia:

  • Prematurity and low birth weight (Incidence approaches 50%.)

  • Urologic conditions

    • Cryptorchidism

    • Hypospadias

    • Epispadias

    • Exstrophy of the bladder

    • Ambiguous genitalia

  • Patent processus vaginalis, which may be present because of increased abdominal pressure due to ventriculoperitoneal shunts, peritoneal dialysis, or ascites

  • Abdominal wall defects

    • Gastroschisis

    • Omphalocele

  • Family history

    • Meconium peritonitis

    • Cystic fibrosis

    • Connective tissue disease

    • Mucopolysaccharidosis

    • Congenital dislocation of the hip

    • Ehlers-Danlos syndrome

    • Marfan syndrome

    • Cloacal exstrophy

    • Fetal hydrops

    • Liver disease with ascites

    • Ventriculoperitoneal shunting for hydrocephalus

• Figures regarding inguinal hernia incarceration indicate the following risk patterns:

  • Incarceration occurs in 17% of right-sided hernias and 7% of left-sided hernias.

  • More than 50% of cases of incarceration occur within the first 6 months of life; the risk gradually decreases after age 1 year.

  • Premature infants have twice the risk of incarceration than the general pediatric population.

  • More than two thirds of all incarcerations occur in children younger than 1 year.

  • Girls are more likely to develop incarceration of an inguinal hernia; the incidence in girls is 17.2%, whereas the incidence in boys is 12%.

See the list below:

• No laboratory studies are needed in the assessment of a patient with a suspected inguinal hernia and/or hydrocele.

Imaging studies are generally not indicated to assess for inguinal hernia. However, ultrasonography can be helpful in the assessment of selected patients.[3]

• Ultrasonography: Some advocate the use of ultrasonography to differentiate between a hydrocele and an inguinal hernia. Ultrasonography is capable of finding a fluid-filled sac in the scrotum, which would be compatible with a diagnosis of hydrocele. However, if the patient has an incarcerated inguinal hernia, ultrasonography may not be sensitive enough to differentiate between the two conditions. Thus, this study is rarely helpful in the treatment of a pediatric patient with a suspected inguinal hernia. When presentation and examination suggest a diagnosis other than hernia or hydrocele, appropriate imaging, including ultrasonography, may be necessary. An enlarged inguinal lymph node can mimic an incarcerated inguinal hernia, and surgical exploration may occasionally be necessary to confirm the diagnosis.

• Peritoneography: Injection of contrast in the peritoneal cavity has been used to determine the presence of a patent processus vaginalis. Although this test is very sensitive, its use is limited. Because of possible complications, including bowel perforation and sepsis, injection of contrast is rarely performed today.

See the list below:

• Laparoscopy: Diagnostic laparoscopy is a very effective method for determining the presence of an inguinal hernia but is used only selectively because it requires anesthesia and surgery. Laparoscopy can be useful to assess the contralateral side (see Treatment) or to evaluate for presence of a recurrent inguinal hernia in patients with a history of operative repair.

See the list below:

• Hernia sacs are composed of fibrous and connective tissue. Embryonal müllerian remnants are recognized in 1-6% of surgical specimens; therefore, the finding of vas or epididymis on the surgical pathology specimen of a hernia sac does not necessarily imply injury.

• Specific histologic features of the remnant include a smaller diameter and failure to show a prominent muscular wall with Masson trichrome staining.

Inguinal hernias do not spontaneously heal and must be surgically repaired because of the ever-present risk of incarceration.[4] Generally, a surgical consultation should be made at the time of diagnosis, and repair (on an elective basis) should be performed very soon after the diagnosis is confirmed. Parents may be instructed on the application of gentle pressure on the bulge of an inguinal hernia to prevent incarceration until the elective operative repair is performed.

• Hydrocele without hernia in neonates: This is the only exception in which surgical treatment may be delayed. Repair of hydroceles in neonates without the presence of hernia is typically delayed for 12 months because the connection with the peritoneal cavity (via the processus vaginalis) may be very small and may have already closed or be in the process of closing. Fluid in the hydrocele comes from the peritoneal cavity and is gradually absorbed if the communication has closed. If the hydrocele persists after this observation period, operative repair is indicated and appropriate.

• Anesthetic management for elective surgery: General endotracheal anesthesia is safe for most surgical repairs of inguinal hernia in infants and children. In addition, either a caudal anesthetic or intraoperative injection of bupivacaine in the inguinal region is used for postoperative analgesia and to minimize the need for intravenous use of narcotics, depending on the parents' wishes and on anesthetic expertise. Occasionally, operative repair is performed under strict local anesthesia, particularly in premature babies, in whom the anesthetic risk is higher. A study by Sun et al found no statistically significant differences in mean IQ scores among healthy children with a single anesthesia exposure during inguinal hernia surgery before 36 months of age compared with siblings with no exposure.[5]

  A Cochrane Review suggested that there is moderate-quality evidence that the administration of spinal in preference to general anesthesia without pre- or intraoperative sedative administration may reduce the risk of postoperative apnea by up to 47% in preterm infants undergoing inguinal herniorrhaphy at a postmature age.[6]

• Umbilical hernias: Most umbilical hernias do not cause any symptoms and do not require surgical repair until approximately age 5 years. For that reason, almost all umbilical hernias in young children and infants are managed by simple observation.

For inguinal hernia, elective herniorrhaphy is indicated to prevent incarceration and subsequent strangulation. Hernia repair is an outpatient procedure in the otherwise healthy full-term infant or child. Postpone the operation in the event of upper respiratory tract infection, otitis media, or significant rash in the groin.

Although adult surgical procedures for correction of inguinal hernias are numerous and varied, only 3 procedures are necessary for the surgical repair of indirect inguinal hernias in children: (1) high ligation and excision of the patent sac with anatomic closure, (2) high ligation of the sac with plication of the floor of the inguinal canal (the transversalis fascia), and (3) high ligation of the sac combined with reconstruction of the floor of the canal. Each procedure can be accomplished with an open or laparoscopic technique.[7, 8]

The first procedure, high ligation and excision of the patent sac with anatomic closure, is the most common operative technique. It is appropriate when the hernia is not very large and has not been present for long. The second procedure, high ligation of the sac with plication of the floor of the inguinal canal (the transversalis fascia), is necessary when the hernia has repeatedly passed through the internal ring and has enlarged the ring, partially destroying and causing weakness in the inguinal floor. The third procedure, high ligation of the sac combined with reconstruction of the floor of the canal, is occasionally necessary in small children with large hernias or when the hernia is long-standing.

The protruding hernia causes gradual enlargement of the ring, progressing to complete breakdown of the transversalis fascia that forms the floor of the inguinal canal. The McVay or Bassini technique of herniorrhaphy is preferred. A description and discussion of the total laparoscopic needle-assisted technique for repair of pediatric inguinal hernias is below; it is a new and innovative procedure that is gaining significant popularity among pediatric surgeons.

• Open repair of the pediatric inguinal hernia

  • The patient should be placed on the operating table in a supine position with his or her legs slightly abducted. The lower abdomen and inguinoscrotal or inguinolabial area and upper thighs must be included in the operative field. The hernia contents must be completely reduced into the peritoneal cavity before the procedure.

  • Incision is made in the skin of the inguinal crease just lateral to the pubic tubercle. The skin incision is typically small (1-2 cm). Electrocautery is used to control any bleeding that may occur.

  • Next, identify and incise the Scarpa fascia. In young children, the Scarpa fascia may be confused with the aponeurosis of the external oblique. However, the Scarpa fascia is smooth, does not have any fibrous bands, and does not glisten like the aponeurosis. In addition, a layer of fat is found beneath the Scarpa fascia but not under the external oblique.

  • One should not raise any skin flaps. Dissection is started through the external oblique at the lateral aspect of the incision and extended to the inguinal ligament.

  • The external ring is identified by dissecting medially along the inguinal ligament. The ring is incised, taking care to avoid injury to the usually visible ilioinguinal nerve. This incision reveals the cremaster fibers of the cord.

  • The hernia sac can be identified in the anteromedial aspect of the cord, and medial retraction of the sac reveals the underlying testicular vessels and vas deferens. Fine tissue forceps are used to tease these structures away from the hernia sac. An Allis clamp may be placed around the vas and the testicular vessels to keep them away from further dissection.

  • The sac can then be clamped and divided. The proximal sac is mobilized to the internal ring, which is often signified by the presence of retroperitoneal fat.

  • Once the sac is confirmed to be empty, it is twisted on itself and doubly suture-ligated with sutures (eg, 4-0 or silk or Vicryl sutures can be used).

  • If the ring is not enlarged, the distal sac is opened to drain any residual fluid and the sac is partially excised. Then, closure is accomplished in layers with absorbable sutures.

  • If the internal ring is enlarged, the cord must be elevated from its bed with a soft rubber drain. A silk suture between the transversalis fascia and the inguinal ligament can be used to tighten the ring. Alternatively, a modified Bassini type of repair can be used to reinforce the inguinal floor.

  • If destruction of the canal floor is present, a reconstructive procedure, such as that of Bassini or McVay, is necessary.

  • The McVay type of repair incorporates a relaxing incision in the rectus sheath that allows the conjoined tendon to be pulled down to the Cooper ligament and the femoral sheath.

  • The incised aponeurosis of the external abdominal oblique muscle is closed with interrupted 4-0 or 5-0 silk sutures or a continuous 4-0 polyglycolic acid suture.

  • Typically one or two interrupted absorbable sutures are used to close the Scarpa fascia. The skin can be closed with absorbable sutures

• Neglected inguinal hernia: In patients with a long-standing history of inguinal hernia, the repeated protrusion of abdominal contents through the inguinal canal enlarges the internal and external rings, reducing the risk of incarceration and strangulation but increasing the likelihood of damage to the posterior inguinal wall. This makes repair more difficult and recurrence more likely. The image below depicts a case of giant bilateral inguinoscrotal hernias in a premature baby. Such a case necessitates elective operative repair.

  A premature baby boy with bilateral giant inguinoscrotal hernias. Because of the large size of the hernias, operative repair typically requires repair of the inguinal floor in addition to the high ligation of the indirect hernia sac.

• Surgery following inguinal hernia incarceration: In the event of surgery for an incarcerated hernia in which the peritoneal fluid is found to be hemorrhagic or cloudy, material should be sent for culture. One must consider enlarging the inguinal incision or creating a counterincision to verify that no nonviable intestine is in the abdomen.

• Inguinal hernia surgery in girls: In girls, a sliding hernia may contain the ovary or a portion of the fallopian tube. These structures should be carefully dissected from the internal wall of the sac before suture ligation. An alternate procedure involves incising the sac along the ovary and tube on either side and folding the flap into the peritoneum. A pursestring suture can then be used to close the sac. In the female, the sac can be sutured closed after division of the round ligament because no important structures pass through the inguinal ring.

• Inguinal hernia surgery and testicular or vas anomalies: An undescended testis discovered during herniorrhaphy should be repaired, even if the infant is younger than 1 year. This repair avoids the complications of incarceration, strangulation, and testicular infarction, while increasing potential fertility. If surgery reveals an absent vas deferens, cystic fibrosis or ipsilateral renal agenesis is present. The second condition results because of the origin of the ureteral bud from the mesonephric duct, the precursor of the vas deferens.[9]

• Exploration of the contralateral side at the time of open repair of an inguinal hernia

  • The question of when the contralateral side needs to be explored is much debated. Advantages for exploration of the opposite side during repair of a known inguinal hernia include the following:

    • Existence of a patent processus vaginalis on the contralateral side (also called asymptomatic hernia) in a significant number of patients

    • Avoidance of second surgery and anesthetic if contralateral patent processus vaginalis becomes symptomatic

    • Eliminated cost of second surgery, if needed

  • Disadvantages include the following:

    • Occasional injury to the vas or testicular vessels during surgical exploration

    • Increased operating time for contralateral procedure

    • May be unnecessary in as many as 70% of all patients undergoing hernia surgery

  • Available literature indicates that neither age nor sex predicts whether a child has a unilateral or bilateral hernia. No diagnostic test can effectively determine the presence of an asymptomatic inguinal hernia. Physical examination alone cannot detect an unsuspected asymptomatic patent processus vaginalis, particularly in infants and small children, nor is physical examination a consistent predictor of the status of the contralateral region.

  • Peritoneoscopy offers the most accurate means of determining whether a child has a contralateral patent processus vaginalis. With the advent of minimally invasive and laparoscopic surgical techniques, diagnostic laparoscopy can be performed through the hernia sac of a unilateral indirect inguinal hernia to determine if contralateral patent processus vaginalis is present. The chance that a small contralateral patent processus vaginalis is present but cannot be identified by means of peritoneoscopy is slight (1%); if this occurs, the patient may subsequently return for contralateral hernia repair once it enlarges with growth. Once a patent processus on the opposite side is verified, most pediatric surgeons recommend that the patient undergo simultaneous repair of the contralateral side under the same anesthesia.

  • Recent experience with the laparoscopic diagnostic technique suggests a high accuracy rate; the false-negative rate is 0.5%, and no significant complications have been reported. Although diagnostic laparoscopy through the ipsilateral hernia sac is not 100% accurate, it is the most reliable method available to determine whether a patient should undergo contralateral inguinal hernia exploration when a known hernia is present.

• Operative technique for diagnostic laparoscopy

  • With the patient under general anesthesia using tracheal intubation, laryngeal mask airway, or mask technique, an orogastric tube is placed for temporary gastric decompression. The Crede maneuver is used to evacuate the urinary bladder. The abdominal, inguinal, and scrotal regions are prepped and draped in the usual sterile fashion.

  • The diagnostic peritoneoscopy can be accomplished through the umbilicus or the upper abdomen, using separate incisions. One preferred method is to perform peritoneoscopy using the ipsilateral hernia sac. Using an inguinal approach, the hernia sac is dissected free from the spermatic cord and traced proximally to the level of the internal inguinal ring. The sac is opened, and a 3-mm to 5-mm reusable cannula is introduced through the hernia sac (see the image below).

    Illustration of the technique for intraoperative diagnostic laparoscopy to evaluate for the presence of an asymptomatic contralateral inguinal hernia at the time of elective repair of an indirect inguinal hernia.

  • The peritoneal cavity is then insufflated with carbon dioxide up to a pressure limit of approximately 6-8 mm Hg. The patient is then placed in Trendelenburg position to facilitate examination of the inguinal region. This position moves the viscera by gravity in the cephalad direction. With a 70° 3-mm laparoscope, the contralateral internal inguinal ring can be seen, and the presence or absence of a patent processus vaginalis can be documented.

  • Once this information is known, the abdomen is desufflated through the metal cannula, the cannula is removed, and open repair with high ligation of the known hernia sac is accomplished. The ipsilateral incision is then closed, and a contralateral exploration is performed if a contralateral patent processus vaginalis has been identified.

• Management of incarcerated hernia

  • When an incarceration is encountered, manual reduction should be attempted if the patient has no signs of systemic toxicity, including leukocytosis, severe tachycardia, abdominal distention, bilious vomiting, and discoloration of the entrapped viscera. If the patient appears toxic, emergent surgical exploration is necessary.

  • Some authors have proposed the use of relaxation maneuvers to relieve the pressure on the neck of the hernia sac and to allow for the incarceration to resolve spontaneously.[10] This involves placement of the sedated patient in the Trendelenburg position of 30-40° to apply mild traction on the entrapped viscera, facilitating reduction. If the hernia has not spontaneously reduced during the 1-2 hours of sedation, gentle but forceful manual reduction by an experienced physician must be attempted.

  • As a rule, forceful manual reduction is recommended in all cases of incarcerated hernia, unless the clinician suspects the possibility of inguinal hernia strangulation. Such attempts are successful in more than 90% of cases and pose minimal risk to the entrapped structure. Successful reduction of an incarcerated inguinal hernia results in immediate patient comfort, relief of obstruction, and prevention of strangulation. Immediate surgery is performed if the reduction is unsuccessful; otherwise, elective operation is scheduled within 24-72 hours after reduction because recurrent incarceration is quite common.

• Manual reduction of incarcerated hernia

  • Once incarceration of an inguinal hernia has been confidently diagnosed, the parents must be informed that reduction of the hernia will be attempted. The patient is placed in the supine position and his or her pelvis is grasped gently but firmly by an assistant to prevent any lateral movement of the buttocks. Depending on the side of the hernia, the ipsilateral leg is then externally rotated and completely flexed into the frog position. This position causes the external ring to ascend so that it more nearly, but not completely, overrides the internal inguinal ring.

  • Once both of these conditions have been established, the first 2 fingers of the guiding hand are placed over the hernial bulge and overriding the upper margin of the external inguinal ring in such a fashion as to prevent the hernia subluxating upwards and over the margin of the ring. Next, the apex of the hernia is grasped between the first 2 fingers and thumb of the reducing hand, and prolonged, steady, firm pressure is applied.

  • This last point is crucial; the reducing hand must not be withdrawn after only a few seconds. One indication of the correct application of this technique is the onset of stiffness in the first 2 fingers and an ache in the thenar eminence. After a given interval that may take minutes, a sudden reduction of the hernia occurs with an almost audible thud, accompanied by complete relief in the patient. Using this method of reduction, open operation of incarcerated inguinal hernia is a rare event. By successfully reducing an incarcerated inguinal hernia, the open operation can be accomplished electively and with decreased morbidity.

• Management of hernia strangulation: Once an incarcerated hernia becomes strangulated, reduction without operative intervention is not possible. Because of significant swelling from the compromised bowel, the presence of intestinal ischemia secondary to incarceration precludes the possibility of reducing the hernia back into the peritoneal cavity. In such cases, immediate operative intervention is indicated, and the viability of the intestine must be carefully assessed at the time of surgery. If necrosis has developed, resect the affected segment of bowel. Incidence of hernia recurrence after emergent surgery for incarceration or strangulation is typically much higher than that reported for elective hernia repair.

• Management of umbilical hernia: Because many umbilical hernias spontaneously close in the first few years of life, elective surgical repair is rarely indicated before school age. Moreover, the occurrence of umbilical hernia incarceration is quite rare. Umbilical hernia repair is quite simple and is typically performed in an outpatient surgical suite. Simple primary closure of the fascial defect under the umbilicus is easily performed using absorbable sutures. A mesh is rarely necessary, only in cases of an extremely large umbilical hernia.

• Laparoscopic needle-assisted repair of inguinal hernia

  • A new and innovative technique for repair of inguinal hernia in young children using a total laparoscopic approach has been described.[11] The technique is described as laparoscopic needle-assisted repair.

  • Standard laparoscopy is performed via a small 5-mm umbilical port with a 5-mm, 30 º- angled laparoscope. Once the indirect inguinal hernia is identified, the laparoscopic repair is performed.

  • The first step is to clearly define the inguinal hernia and the lateral and medial border of the open internal inguinal ring. This is accomplished by probing the groin region with a small 22-gauge needle.

  • Under careful laparoscopic-guided visualization, a 22-gauge Tuhoi spinal needle with a 2-0 Prolene suture thread inside the barrel of the needle is inserted and passed underneath the peritoneum and the inguinal ligament, lateral to the internal inguinal ring, away from the spermatic vessels and vas. All needle movements are performed by the operating surgeon from outside the body cavity under direct laparoscopic control so that the position of the tip of the needle can be precisely placed at the desired location inside the peritoneal cavity. The Prolene thread is than pushed through the barrel of the needle into the abdominal cavity, creating an internal “loop." The needle is pulled out, leaving the Prolene loop of the thread inside the abdomen.

  • From the outside the patient’s body, one of the threaded ends is introduced again into the barrel of the spinal needle, and the needle is passed through the same skin puncture point, through the medial aspect of the internal inguinal ring, under the peritoneum. Again, the vas and vessels are mobilized to stay away from the needle, in order to prevent any injury. Once the tip of the needle is in the desired position next to the loop of Prolene, the thread is pushed in so that it passes through the loop. At this point, the thread-loop is pulled out of the abdomen, with the thread end caught by the loop. In this way, the suture thread of Prolene is placed around the internal inguinal ring under the peritoneum, creating a complete purse-string suture with the ends of the suture coming out of the same skin needle hole in the groin region. The knot is tied to close the internal inguinal ring and hernia opening. With this technique the knot is buried in the subcutaneous tissue.

  • The images below illustrate the laparoscopic needle assisted repair of a left indirect inguinal hernia.

    Laparoscopic view of a left indirect inguinal hernia at the time of surgery for laparoscopic needle-assisted repair.
    Laparoscopic needle-assisted repair of a left indirect inguinal hernia. Note the passage of a Prolene suture through a small 22G spinal needle; this is used for creation of the purse-string suture that closes the open inguinal ring.
    Laparoscopic view of the repaired left indirect inguinal hernia with the closed Prolene purse-string suture around the internal inguinal ring.

  • If an open internal inguinal ring is identified in the contra lateral side, it is closed using the same technique through a small needle hole in the opposite groin.

  • This fairly new technique has had great acceptance among many pediatric surgeons. Because of the very small skin incisions, it is associated with minimal pain and has great cosmetic appeal. Preliminary results suggest a similar recurrence rate as reported for the open technique.[12] However, long-term outcomes have not yet been reported. The author's group at the Medical University of South Carolina conducted a prospective outcome analysis comparing the laparoscopic with the open technique. The author group reported that post-operative data showed that the laparoscopic needle-assisted repair of inguinal hernia (LNAR) technique is safe with a 4% rate of minor complication. The study further reported that the recurrence rate is comparable and in many cases less than open technique. The author group also added that laparoscopy objectively identifies asymptomatic or occult contralateral defect, uses a smaller incision, and eliminates dissection of the cord structures potentially reducing the risk of cord injury.[13]

    Another study that utilized a single port laparoscopic percutaneous repair (LPHR) technique for selected children requiring operative intervention for inguinal hernia, compared operative times and surgical outcomes in patients undergoing LPHR versus traditional open repair. The study concluded that in select patients, LPHR is an efficient, safe, and effective minimally invasive alternative to open repair, with reduced operative times but without increased rates of complications or recurrences.[14]  

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• Consult a pediatric surgeon when a diagnosis of inguinal hernia or hydrocele is suspected. In the event of incarceration and/or strangulation, request an urgent consultation.

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• No dietary restrictions are indicated in the treatment of children with hernias.

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• No specific limitations are indicated once the diagnosis of an inguinal hernia has been established; however, following operative repair, avoidance of major physical activity for 1 week is recommended. After that time, the patient is allowed to participate in physical activities (eg, sports, swimming, running).

• Children younger than 5 years are likely to recover extremely quickly from surgery; they are typically capable of returning to their normal level of activities within 24-48 hours of surgery.

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• No effective nonoperative therapy for treatment of an inguinal hernia in a child has been identified. See Treatment.

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• Routine follow-up care after operative repair of an inguinal hernia typically requires only one office visit or telephone consultation if the parents have reported no problems or complications. Scrotal swelling and bruising after surgery are common and may last for 1-3 weeks. Such signs do not indicate any complications; they represent normal postoperative changes.

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• Most patients who undergo elective repair of an inguinal or umbilical hernia are discharged from the hospital shortly after surgery. Overnight observation is indicated only in small premature babies who are at risk for postoperative apnea. Such patients are usually admitted for 24-hour observation and monitoring in the hospital.

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• Most patients are treated with acetaminophen for 24-48 hours after surgery. Codeine is occasionally added for pain management in older children (>1 y).

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• Transfer to a facility with pediatric surgical expertise is indicated in premature babies with inguinal hernias or in the event of inguinal hernia incarceration and/or strangulation.

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• Few complications result from operative repair of an inguinal hernia. Possible consequences of hernia repair include decreased testicular size (≤ 20% of patients), testicular atrophy (1-2%),[16] vas injury (< 1%), and development of sperm-agglutinating antibodies. The risk of gonadal injury in females is low. Fortunately, in the hands of pediatric surgeons, such complications are quite rare.

• The incidence of wound infection is 1-2%.

• Hernia recurrence rates are around 1% when experienced pediatric surgeons perform the operation. Factors associated with recurrence of inguinal hernia include an unrecognized tear in the sac, failure to repair an enlarged inguinal ring, damage to the canal and inguinal floor, infection, history of incarceration, connective tissue disorder, and conditions producing increased intra-abdominal pressure (eg, chronic respiratory problems, constipation). The hernia recurrence rate with the laparoscopic technique has been reported to be higher if the surgeon is still in the "learning curve." However, in the hands of an experienced surgeon, the recurrence rate for the laparoscopic technique should be similar to the one reported for the open technique. 

  A study that included data from 9,993 pediatric patients who underwent inguinal hernia repair reported a recurrence rate of 1.4% with an incidence of recurrence 3.46 per 1000 person-years. The study also found that the majority of recurrence occurred within a year and children with multiple comorbidities had a greater risk of recurrence.[15]

• The vas deferens and ilioinguinal nerve occasionally may be injured and should be repaired with 7-0 or 8-0 Maxon sutures. This may be technically difficult because of the extremely small vas lumen not traversed by semen. One infertility expert advises marking the ends of the vas with permanent suture and performing vasovasotomy after puberty with a 2-layer closure. It is also important to remember that the finding of vas or epididymis on the surgical pathology report does not necessarily imply injury because embryonal müllerian remnants have been recognized in 1-6% of surgical specimens. Specific histologic features of the remnant include a smaller diameter and failure to show a prominent muscular wall with Masson trichrome staining.

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• Overall prognosis is excellent; most patients do extremely well after operative repair of their inguinal hernia. Mortality is extremely rare but, unfortunately, continues to be reported as a consequence of delayed recognition of an incarcerated and strangulated inguinal hernia.

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• Instruct parents and caretakers on the signs and symptoms of inguinal hernia incarceration. Delayed recognition of incarceration is likely to result in significant morbidity and mortality for the child.

• For excellent patient education resources, visit eMedicineHealth's Digestive Disorders Center. Also, see eMedicineHealth's patient education article Hernia.