Individualized Treatment of Inguinal Hernia in Children

Abstract

The inguinal hernia is the commonest type of hernia in children. Either scheduled or as an emergency, hernia surgery is performed daily in every pediatric surgical institution worldwide, regardless of age or gender. In this chapter, we discuss the embryology of the inguinal canal and its pathophysiological association with hernia formation. We also present the most frequent clinical and diagnostic issues of the pediatric hernia. The management of strangulated hernia, differential diagnosis, and the particular uncommon hernia types are presented as well. We finally present the evolution of hernia surgery from the classical operative methods to the modern laparoscopic techniques.

1. Introduction

Inguinal hernia is the most common congenital disorder in daily pediatric surgical practice. It may be managed in a tactical manner or appear as an organ and life-threatening event that requires urgent treatment in cases of testis, ovary, or intestinal entrapment (incarceration and strangulation of hernia). In this chapter, the particular characteristics, the diagnosis, and the current management of inguinal hernia in children are described in detail.

2. Incidence

A hernia is defined as a protrusion of an organ or tissue, through an abnormal opening. Congenital inguinal hernia is one of the most frequent congenital conditions, most commonly encountered from birth until the age of 6 years [1]. It may be divided into two types, the indirect (prevailing in childhood, 99% of cases) and the direct which is rare in children. The accurate incidence of indirect inguinal hernia is unknown as an effect of factors, such as prematurity, associated disease, and medical accessibility. However, indirect inguinal hernia is observed approximately in 1–5% of the term males, who outnumber females with a predominancy of 80% [2]. It is mostly encountered on the right side (60%). A total of 10% of the cases are bilateral [1, 2, 3].

There is a higher incidence of indirect inguinal hernia in preterm infants as well as in conditions of increased intra-abdominal pressure. Abnormal abdominal content as with ascites or during peritoneal dialysis, as well as abnormal abdominal wall disorders, such as exomphalos, gastroschisis, and bladder exstrophy, may increase the incidence of indirect inguinal hernia. Prematurity also seems to increase the incidence (2–30%) and the frequency of incarceration (1–6% during the first 6 months of life). Therefore, correction is strongly advised before hospital discharge [4]. Cystic fibrosis, congenital collagen conditions such as Ehlers-Danlos syndrome, mucopolysaccharidoses (Hunter-Hurler syndrome), and congenital hip dislocation are frequently associated with higher incidence of hernia rates. Cystic fibrosis has higher inguinal hernia incidence, up to eight times the general population and mucopolysaccharidoses are associated with a recurrence rate of 50%. Recurrence may be a primary symptom of the disease in these patients [4, 5]. Direct inguinal hernia is rare in children, mainly diagnosed during surgery, and may be a result of inguinal floor trauma after surgical reconstruction of indirect hernia or as a result of higher intra-abdominal pressure.

3. Bilateral inguinal hernia

The incidence of bilateral inguinal hernia is not clearly defined. This occurs because the consideration of the patent processus vaginalis as a potential for causing actual hernia is still under debate. However, there are predisposing factors, such as gender, age, and the side of the precedent hernia, which seem to favor bilateral presentation and the necessity of simultaneous treatment of both sides [5]. Female gender, left-sided hernia, and prematurity seem to favor postoperative contralateral hernia appearance. Collagen disorders, cystic fibrosis, and ventricular-peritoneal shunts are followed by higher bilateral rates and present higher risk of anesthesia complications.

Bilateral management is recommended in preterm infants due to high incarceration risk, and in infants and young children with the prementioned disorders, in patients with a history of incarcerated hernia, and in patients under increased anesthetic risk. The final medical decision is patient-personalized in cooperation with the parent and in accordance with the current data.

4. Embryology and pathophysiology

To fully understand the inguinal hernia embryology and pathophysiology, some evidence of the inguinal canal formation and the testicular descent should be recalled.

4.1 Formation of the inguinal canal

The dynamic development of the inguinal canal is closely connected to differentiation of the gonads and their migration into the scrotum. The inguinal canal is established in both sexes even though testicular descent occurs in the male, while in the female the ovary remains inside the pelvis as the Fallopian tube acts as a barrier. In the female, the gubernaculum becomes the round ligament [6].

4.2 Testicular descent

The intra-abdominal differentiation of the male gonad is followed by its descent through the inguinal canal, guided by the gubernaculum. The gubernaculum originates in two triangular mesenchymal condensations, the inguinal plica dorsal to the Wolffian duct and the inguinal crista opposite the plica [6, 7]. The growth and differentiation of the gubernaculum is induced by insulin-like factor 3 (INSL3), which is secreted by Leydig cells [8, 9]. The pelvic portion of the gubernaculum is created by merging the mesonephric and inguinal portions. The inguinal portion continues to extend as far as the superficial inguinal ring, which is formed by the external oblique muscle. Condensation of the mesenchyme progresses caudally to form the scrotal part of the ligament. Notably, the gubernaculum is not connected to the gonads at any time during embryogenesis. At the end of this period, the vaginal process appears as a protrusion and evagination of the peritoneum that surrounds the pelvic and inguinal portion of the gubernaculum.

It is controversial as to whether the gubernaculum acts as a guide through the inguinal canal or actively pulls the testis into the scrotum. In contrast to males, in females it is remodeled into the round ligament in female fetuses. Herein, the vaginal process reaches only the initial section of the inguinal canal and the ovaries do not reach the abdominal wall [7].

At the 32–35th gestational week, the gubernaculum descends from the region of the internal inguinal ring, accompanied by a parietal peritoneal diverticulum, the future vaginal process (processus vaginalis), to its final destination in the scrotum, through the anterior wall muscles [6]. More specifically, it is accompanied by the transversalis fascia, and the internal and external oblique abdominal muscles, which form the final testicular layers in the scrotum. During further development, the vaginal process elongates and eventually envelops the gubernaculum.

The vaginal process normally obliterates around the 35th week of gestation and becomes the tunica and processus vaginalis. Failure of this obliteration leads to a persistent vaginal process that may result in an inguinal hernia or a hydrocele depending on what the content is, either an intraperitoneal organ or a peritoneal fluid. In both cases, the final management target is occlusion of the processus vaginalis [6].

The testicular vessels and vas deferens are retroperitoneal structures that exit the internal ring behind the gubernaculum and the vaginal process. As a result, the future processus vaginalis lies anteriorly and slightly medially to the spermatic cord structures. When the processus remains patent, a potential hernia results, and may become an actual hernia when an intra-abdominal content exits the cavity into it. The sac of hernia can be extremely thin or thick according to the age of the patient, the symptoms, or the incarceration occurrence [6, 7].

5. Clinical presentation

Indirect inguinal hernia may present as an inguinal protruding mass toward the scrotum in boys or descending toward the labia in girls. It is easily observed in conditions of enhanced intra-abdominal pressure and may spontaneously reduce after gentle lateral pressure.

It is not unusual for a bulge to be felt by the patient during clinical examination. The silken cord sign may be revealed by careful palpation, as thickening and slipperiness of the cord structures during examination of the inguinal channel [10]. In general, a careful history in combination with a careful examination set the diagnosis [11].

When there is no sign during examination and only a pediatric note is available, a good history-referring to a recurrent inguinal bulge, which is spontaneously reduced or gradually becoming difficult in reducing, is adequate to proceed with surgery. An ultrasound may seem useful. A firm, tender mass occupying the inguinal canal and possibly extending to the scrotum may be the first sign of an inguinal hernia (possible acute obstructed hernia) and requires urgent management [11].

Direct inguinal hernia is rare, noticed as a protruding inguinal mass close to the epigastric vessels, either spontaneously or after provoked higher intra-abdominal pressure. A history of previously surgically corrected ipsilateral inguinal hernia may be noted.

6. Diagnosis

The clinical features, combined with a careful history and an inguinal ultrasound occasionally, set the diagnosis. Inguinal hernia should be differentiated from a hydrocele. Differential diagnosis includes the potential acute scrotum etiology in cases of a painful inguinal mass not previously noticed. All the potential inguinal mass situations include torsion of the testis or the testicular appendages (Sinopidis [12]), infection, and trauma. A careful history, a thorough physical examination, and a regional ultrasound may differentiate all these situations from a hernia.

The hydroceles are asymptomatic inguinal, scrotal, or inguinoscrotal, nonsensitive masses that can be intermittently seen. An empty scrotum in the morning, which progressively enlarges throughout the day, is typical of a communicating hydrocele. It can be slowly reduced by sustained pressure during examination. The transillumination sign can be diagnostically helpful. Hydroceles are corrected with surgery only in children older than 12–18 months, when the process vaginalis is unlikely to close. The idiopathic scrotal edema appears as edema of the scrotum in total accompanied with external irritability and regional erythema. There is no processus vaginalis or testis interference. Finally, a tumor may occur, although a rarity [11].

7. Uncommon hernia types

Content of hernia sac usually includes omentum, small and large intestines, lateral ankle of bladder, and ovary in female [Scott]. Rarely, content may include the appendix (Amyand’s hernia), Meckel’s diverticulum (Littré’s hernia), or only a part of the small intestine (Richter’s hernia).

7.1 Amyand’s hernia

Amyand’s hernia is a hernia that contains the vermiform appendix. It is extremely rare, with an incidence of 0.5–1%. It mainly occurs in the right inguinal region, but it may be found as well in the left inguinal area, due to mobile cecum, malrotation, or situs inversus [13]. The presence of a noninflamed appendix in the inguinal hernia is three times more common in children than in adults, due to the persistent patency of the processus vaginalis in infancy and childhood [13]. The pathophysiology of acute appendicitis in the inguinal canal is under controversy. It is not certain whether a relationship exists between incarceration and inflammation, or whether it is incidental [14]. Amyand’s hernia is usually diagnosed during surgical exploration of the groin, though ultrasound can prove helpful in children [14, 15]. Neonatal appendicitis is extremely rare (0.1% of appendicitis cases in infancy, which constitutes 2% of pediatric appendicitis). Premature neonates account for 50% of these cases, and in one third of these, the inflamed appendix lies within a hernia. Enterocutaneous fistula secondary to appendicitis in an Amyand’s hernia is also extremely rare [14].

7.2 Littré’s hernia

Meckel’s diverticulum (MD) occurs as a result of incomplete obliteration of the omphalomesenteric duct during fetal development. It is typically found at the antimesenteric border of the ileum, usually located from 30 to 90 cm from the ileocecal valve, presenting occasionally ectopic gastric or pancreatic mucosa, and remains asymptomatic in 91–96%. When symptomatic, it appears frequently as hemorrhage, perforation, inflammation, and obstruction [16]. Involvement of a MD in a hernia is known as Littré’s hernia (LH) [17]. In LH, a protrusion of the MD through a remaining patent processus vaginalis is observed in less than 1% of MD cases, usually on the right side and it is difficult to diagnose before surgery. It is more frequent in boys, but overall rare in children [18]. LH has been divided into two distinct subtypes. A true one, which is more common, contains Meckel’s diverticulum. A mixed type contains a segment of small bowel in addition to MD and is less commonly reported [18]. The clinical preoperative diagnosis remains difficult, even in cases of strangulated inguinal hernias, whereas obstruction can occur if the base of the diverticulum is broad enough to cause narrowing of the intestinal lumen [19].

7.3 Richter’s hernia

Richter’s hernia is formed when the antimesenteric border of intestine protrudes into the hernial sac, but it never involves all the intestine. Such a protrusion through the inguinal canal is a rare clinical entity and evolves 12–36% of all presentations. The femoral ring (36–88%), postincision hernias (4–25%), spigelian hernias, and the umbilicus (extremely rare) are other possible locations [20, 21] The hernial sac usually contains a segment of the distal ileum, however any part of the gastrointestinal tract may be involved. Pediatric evidence is scarce, and our knowledge is mainly based on the adult population [20]. Clinical presentation is often misleading. An abnormal internal ring predisposes to strangulation and blood supply compromise, leading to ischemia and intestinal necrosis. Compared with patients with other hernias, patients with Richter’s hernias have greater preoperative delay, rate of bowel resection, length of hospital stay, and postoperative morbidity and mortality rates [21].

8. Complications

Inguinal hernias can be strangulated and incarcerated. Premature children are susceptible to hernia incarceration (up to 60% during the first 6 months of life) [11]. The intestine as well as the ovaries or the fallopian tube can be incarcerated. The patient presents irritability and complains of groin pain. When the bowel is strangulated, cramping abdominal pain, vomiting nonbilious at first but rapidly progressing to bilious one, signs of ileus can be found. The physical examination reveals a firm, painful nonreducible mass in the inguinal area or even extending to the scrotum. Blood may be revealed in rectal examination in cases of intestinal necrosis. A history of known hernia in the affected area might be noted. Incarceration might sometimes be the first clinical presentation of an inguinal hernia. Incarcerated hernias with no signs of strangulation can be reduced nonoperatively in 80% of cases, followed by surgery in elective time. However, failure of reduction after three manual attempts or a hernia that remains unreduced after 2 h, including after attempt of gentle manual reduction, requires urgent surgical reduction and repair as further delay may jeopardize the sac contents, as well as the testis in the male [11].

9. Surgical management

Surgical repair is the definitive treatment of an inguinal hernia. Although such an operation is one of the most common methods in pediatric surgery, many issues arise, concerning the kind of anesthesia, the technique used in either elective or urgent fashion, the timing of the repair, especially for the preterm infants, and the contralateral exploration during surgery for unilateral inguinal hernia.

10. Anesthesia

General anesthesia is a golden standard option in pediatric surgery. In expert hands, there is a very low risk of complications, with postoperative apnea being the most common. Moreover, the use of antidotes makes this technique more suitable for short duration procedures [22]. However, general anesthetics and sedatives have been accused of having possible, harmful effects on the developing brain of a child [23]. General anesthesia, especially in preterm infants, can cause apnea and bradycardia postoperatively, meaning a reduced blood flow to the brain [24]. Such a decrease in oxygen supply could negatively affect the development of the central nervous system [25]. Although not the most appropriate for small duration procedures, regional central anesthesia is gaining ground. It is more cost effective than general anesthesia [26], creates minimal cardiorespiratory disturbances [22, 27], prevents the complications of high-risk patients with difficult intubation, is better tolerated in patients with respiratory diseases [28], and decreases neuroendocrine stress as a response to surgery [29].

One of the major issues of spinal anesthesia is the high failure rate that can reach 20% of the cases [30]. On the contrary, there is no mention of failure for general anesthesia. No fatal incidents have been reported during regional central anesthesia. The complications of this technique are usually minor. The most usual are post-dural puncture headache (2–4%), back pain (5–10%), and transient neurological symptoms (3–4%) [31].

11. Timing of operation

One of the most debated issues, concerning inguinal hernia repair in children, is the timing of operation, especially in preterm infants. It is common knowledge among pediatric surgeons that in full-term infants and children of any age, without other comorbidities, an inguinal hernia should be repaired soon after diagnosis [32].

However, in preterm infants. The optimal timing to perform surgical repair (before or after hospital or neonatal intensive care (NICU) discharge) remains controversial, due to the difficulty of balancing the risk of incarceration against the risk of intraoperative and postoperative complications [33, 34]. One of the first attempts to overcome this problem was the choice of many pediatric surgeons in the late 1990s and early 2000s, to opt for an operation when the child was at least 2 kg of weight, trying in such manner to minimize as possible the risk of strangulation concurrently with the risk of intraoperative and postoperative complications, although a lot has changed since then.

Some researchers argue that the risk of incarceration in infants is increased at least twofold, if the surgical repair gets delayed 14 days after diagnosis, reaching 60% of the cases, especially in preterm infants [35, 36]. On the other hand, many studies have demonstrated no significant difference in incarceration rates between patients undergoing hernia repair before (18.1%) and after (11.3%) discharge [37, 38, 39, 40, 41]. Of note, weight (either at birth or at incarceration), prematurity, sex, and side did not significantly correlate with the incidence of incarceration [42]. Many surgeons have also reported that early surgery for inguinal hernia in preterm infants increases five times the risk for postoperative apnea and ventilator dependence, with a maximum percentage of 4.7 in case of infants with postconceptional age less than 45 weeks [41, 43]. More specifically, respiratory problems were reported in 5.1 and 3.3% of the patients with early and late repair, respectively [37, 38, 39, 40, 44]. Moreover, many surgeons have observed a 1–9% possibility of recurrence, if preterm babies were operated before discharge, due to the small anatomic area during surgery and the friable hernia sac [42, 45, 46]. Between preterm patients with early repair of inguinal hernia and those with late repair, the recurrence rate was 5.7% against 1.8% [37, 38, 39, 40].

The European Pediatric Surgeons’ Association Evidence and Guideline Committee concluded that no significant differences were found for incarceration between early and late surgical intervention in preterm infants with inguinal hernia. However, the late repair of a hernia after discharge from the hospital or NICU in a preterm infant will have better outcomes in terms of respiratory complications and hernia recurrence [41]. To sum up, a hernia in healthy full-term children should be electively repaired soon after diagnosis. On the other hand, the perfect timing for the repair of a hernia in a preterm infant is not 100% clear and every single case should be considered according to the specific needs of the patient.

12. Contralateral exploration

The exploration and repair of a contralateral patent processus vaginalis is still a matter of debate. It has been reported that gender, age, and birth weight have no influence on the development of a contralateral metachronous hernia [47, 48]. Many surgeons prefer to explore and repair the contralateral side, especially if the patient has birth weight less than 1500 gr, if it is a female, and if the operation is scheduled for a left-sided hernia [42]. It can be understood that during laparoscopic surgery, the inspection of the contralateral side is very easy to perform, but in case of open surgery, the exploration of the other side implies an increased risk of vas deferens and vessels’ injury.

According to literature, the likelihood of a patent processus vaginalis in the opposite side ranges from 20 to 70% [36, 41, 49, 50, 51]. However, the overall presentation of a metachronous hernia in an initially asymptomatic contralateral processus vaginalis does not exceed 11.6% [41, 47, 48, 51, 52, 53, 54]. Although the fact that such a percentage increases if the patient is preterm or less than 1 year of age, female, with a left-sided initial hernia, it must be underlined that the routine repair of a contralateral explored, asymptomatic patent processus vaginalis during laparoscopy or the choice to proceed to the opposite side during open surgery may result in overtreatment [42, 50, 53].

As regards laparoscopic procedures where the contralateral side is easily explored for a patent processus vaginalis, 20 procedures must be performed to avoid one metachronous inguinal hernia [51, 54]. For these reasons, European guidelines affirm that exploration and repair of the opposite site during surgery for unilateral inguinal hernia in children may prevent the development of a metachronous one, but such practice should not become the routine method because of the extensive heterogeneity among the currently available evidence [41].

13. Surgical technique through inguinal incision

The most common approach for repair of an inguinal hernia in children is through an inguinal incision. With the patient in supine position, a small cut is made through the dermis in the middle of the line that connects the anterior superior iliac spine and the pubic tubercle. The incision continues down to the subcutaneous fat, Camber’s and Scarpa’s fascia. Ladd and Gross, the fathers of pediatric surgery, preferred to open the external oblique muscle and perform reconstruction of the inguinal canal (Ferguson procedure), while others avoid entering the inguinal canal (Mitchell-Banks repair) [55].

The internal and external rings in the neonate are almost overlapping anatomically. As the patient grows, some distance is observed between the two, which in the adults results in 4 cm. The external oblique muscle is opened with a longitudinal incision to its fibers. The sac is identified beneath the transversalis fascia and the cremasteric muscle, which is dissected taking care not to traumatize the ileofemoral and ileoinguinal nerves. The hernia sac is grasped, and the cord structures are dissected gently, without injuring the vas deferens and the spermatic vessels in males, while in females such risk does not exist.

The sac is clamped, ligated, and divided. The distal part may be left without ulterior manipulation, due to the risk of injury of the testicle. The proximal part is dissected until the level of the internal ring twisted on itself and double ligated with monofilament absorbable suture and ligated. Routine inspection of the testis is not needed, but if so, particular care should be taken to place the testis in its right position inside the hemiscrotum. The surgical wound is closed in layers according to the right anatomical order. The skin is closed with subcutaneous suture for a better esthetic result. A dressing protects the wound from stools and urine.

In females, 40% of the inguinal hernias are sliding hernias. For this reason, the proximal part of the sac is opened, explored, and any structures are reduced inside the abdominal cavity. If the ovary or the fallopian tube makes part of the wall of the inguinal sac, the closure of the sac is performed by placing an external purse-string stitch above the level of protruding structure and then invert the sac in the internal ring, which is closed with sutures (Bevan repair) [56].

14. Laparoscopic procedure

The first to report a laparoscopic hernia repair was El-Gohary, but he only operated in females [57]. The transabdominal purse-string stitch technique was presented for the first time by Montupet and Esposito in 1999, which was, also, the first successful laparoscopic inguinal hernia repair in boys [58]. It is one of the most used among pediatric surgeons, although multiple laparoscopic techniques have been proposed. Scier described his intracorporeal repair with z-stitches of the processus vaginalis in females only and 12 years later, he described a similar procedure in males, but used several interrupted stitches than the z-suture to close the sac [59].

Many other techniques for transabdominal repair have been presented with small novelties, such as injection of normal saline (2 ml) into the extraperitoneal space to elevate the peritoneum away from the vas deferens and the testicular vessels, division and suture of the patent processus vaginalis at the level of the internal inguinal ring, use of the peritoneum to cover the processus vaginalis, and circumferential division of the peritoneum at the deep ring by purse-string closure of the proximal peritoneum [60, 61, 62, 63].

Prasad et al. in 2003 presented for the first time the extraperitoneal repair [64]. Since then, a variety of devices and slight modifications have been described to improve the extracorporeal technique [65, 66, 67, 68, 69, 70, 71, 72, 73].

Some researchers have combined the open and laparoscopic techniques for a better overall result [74]. The transabdominal laparoscopic hernia repair is performed with the patient in the supine position. A foley catheter is always placed, to avoid injury to the bladder. After the placement of a 5 mm trocar transumbilically, pneumoperitoneum is achieved with a pressure of 8–12 mmHg, according to the size of the patient. Two 3 mm small incisions in the right and left lower quadrants are made and two 3 mm trocars are placed. Usually, the surgeon is positioned in the contralateral side of the hernia and the monitor in the ipsilateral side. Obviously, any hernia contents are reduced before beginning repair of the hernia. In males, the cord structures are identified and carefully excluded from the purse-string stitch that will close the sac, while in females many include the round ligament in the purse-string stitch. After completion of the operation, the gas used is removed from the peritoneal cavity. The 3 mm wounds do not require stitches and can be closed with steri-strips or skin glue. The wound of the umbilicus is closed with absorbable stitches in layers according to the right anatomical order. The contralateral side can be easily evaluated, and bilateral repair can be performed if necessary.

In the extracorporeal procedure, the only port used is the one in the umbilicus. The level of the internal ring is identified with palpation and compression. A small incision is made anterolateral to the ring itself. A curved awl that bears a suture is passed around the lateral half of the internal ring. After half of the sac is surrounded by the suture, the awl pierces the peritoneum, and the suture is grasped. The empty awl is withdrawn and reinserted into the wound. It passes around the medial half of the internal ring and once more enters the peritoneum at the same point the suture is left, previously, in the abdominal cavity. Care must be taken to exclude the vas deferens and vessels. The suture is passed through the awl and the awl is pulled out of the abdomen completing the purse string. The knot is tied extracorporeally and buried in the subcutaneous tissue.

A special note must be made for the extraperitoneal repair described by Patkowski et al. (percutaneous internal ring suturing, PIRS) and used as minimal invasive procedure by many surgeons in the modern era [68]. An 18-gauge injection needle, with a nonabsorbable 2–0 monofilament thread inside the barrel of the needle, is introduced into the abdominal cavity under laparoscopic guidance, leaving the ends of the thread outside the patient’s body. By moving the tip of the needle, the thread passes under the peritoneum, over the half of the internal ring including a part of the ligament and adjacent tissue. The thread is pushed through the barrel of the needle and a loop is created. The needle is pulled out and one of the ends of the thread is introduced once again inside the peritoneal cavity in the same manner as that described before. Care is taken to puncture with the needle the same point on the skin. This time the thread surrounds the other half of the internal inguinal ring including once more part of the ligament. To avoid injury to the vas deferens and vessels, a small space is left above these structures. The end of the thread goes through the barrel of the needle into the loop and the needle is withdrawn. The thread loop is pulled out of the abdominal cavity, with the thread end caught by the loop. In this way, the thread is placed around the internal ring under the peritoneum, and both ends exit from the same point on the skin. A knot is made to close the inguinal ring and placed under the skin.

Single-port laparoscopy procedures, intracorporeal and extracorporeal, have been described. Such techniques seem to be a feasible and safe alternative to repairing inguinal hernia in the pediatric population [75, 76].

15. Open versus laparoscopic hernia surgery

When comparing the open procedure with the laparoscopic methods, we evaluate the operative time, the recurrence rates, metachronous hernia rates, the lengths of hospitalization, and the complications. Perioperative complications include injury of the vas deferens and spermatic vessels in males and ovaries in females, bleeding, and bowel trauma. Postoperative complications are testicular atrophy, iatrogenic ascent testis, hematoma, edema, hydrocele, and wound infection.

Unilateral repair of inguinal hernia in children has no difference in operative time between open and laparoscopic techniques, although most of the researchers agree that in females, both procedures last less [77, 78, 79, 80, 81, 82]. Some of them have presented shorter operative time with the laparoscopic repair for unilateral hernia, especially with the PIRS procedure, but insist that the learning curve and, thus, the experience of the surgeon is of great importance [41, 82, 83, 84]. Recurrence rates are similar in both techniques, ranging from 0 to 6.3% for open surgery and from 0 to 5.7% for the laparoscopic procedures [77, 79, 80, 81, 82, 85]. Some researchers argue that the risk of recurrence after laparoscopic surgery is much higher, even reaching 26.7% of the cases [86]. Such a high percentage of recurrence is justified by many, because of the surgeon’s inexperience and comorbidities of the patients, especially pulmonary diseases [87, 88]. Moreover, most of the studies present an average follow-up of 2–3 years of the patients who have undergone surgery, while some studies claim that a follow-up of at least 5 years is necessary to put on display the majority of the recurrences [89].

As regards the rates of metachronous contralateral hernia, the results are controversial. On the one hand, there are researchers who claim that no difference is demonstrated between open and laparoscopic procedures [79, 82, 90, 91]. On the other hand, there are studies that present a percentage of 5.9% of metachronous hernia in the open repair and near to zero in the laparoscopic procedures. This is, easily, understood, because of the easy inspection of the contralateral side in a laparoscopic surgery, although, as mentioned, a treatment of every patent processus vaginalis can result in overtreatment [91, 92, 93, 94, 95]. The length of hospitalization (4–6 h), postoperative pain, and, consequently, the time for a full recovery do not show significant differences between the two techniques [77, 79, 80, 81, 82, 90].

Perioperative complications like bleeding (5.7%) testicular injury or trauma of the vas deferens or the vessels (0.13–1.6%) and ovarian lesion seem to have the same rates between open and laparoscopic procedures [77, 81, 85, 89, 91]. With regard to postoperative complications, most of them conclude that there are no significant disparities between open and laparoscopic procedures, although testicular compromise can range from 2.6 to 13%, especially in case of strangulated hernias [77, 79, 80, 89, 90, 91]. Nonetheless, some claim that open and laparoscopic repairs present slightly different rates for some postoperative complications. For example, testicular atrophy can range from 0 to 13% of the cases in open repair, while in laparoscopic procedures this percentage is almost zero. The same applies to injury of the spermatic vessels, which in open procedures reaches a percentage of 1.6%. The risk of iatrogenic ascent testis was more pronounced in laparoscopic surgery (3.2%), whereas in open surgery it was 1.2–2.7%. Hydrocele formation was seen in 2.9 and 5.7% of the cases in open and laparoscopic procedures, respectively [81, 91, 96, 97]. Finally, most studies concur that the cosmetic results of the laparoscopic procedures are superior if compared with those of the open surgery [70, 71, 79, 80, 81, 85, 92, 98].

16. Management of strangulated hernia

If the surgeon is certain that there is no compromise of an internal organ, a reduction maneuver can be attempted. The patient is laid in a supine position. The sac with the incarcerated bowel lies in front and anteriorly of the external inguinal ring in such a fashion that the ridge of the ring is covered by the sac and its content. Standing next to the patient, the surgeon must perform a maneuver of gentle continuous pressure of the herniated bulge with one hand, while with the other hand, firm pressure to the margins of the external ring is applied, to prevent overlapping the ridge, and obtain reduction into the inguinal canal.

The success of the procedure can be understood by the relief of the patient and from a sensation of sudden liberation in the fingers that apply pressure to the bottom of the hernia, usually accompanied with a characteristic sound. This maneuver can last for several minutes and can be facilitated by light sedation or intramuscular administration of pethidine. It is recommended to conduct the follow-up of the patient for 24 to 48 h, to observe the stools, since reduction of gangrenous intestine has been reported [99]. The definitive repair of the hernia should be delayed for at least 48 h, due to edema of the tissues.

In case of peritonitis or signs of shock, due to serious bowel compromise or if the manual reduction fails, broad-spectrum antibiotics are administered, a nasogastric tube and a foley catheter are placed, and the patient is promptly brought to the operation room. We should mention that in females, the strangulated organ can be a part of the intestine or the bladder, but, also, an ovary, a fallopian tube, or the mesosalpinx. General anesthesia is, sometimes, sufficient for the reduction of the hernia, nonetheless the operation should proceed.

The operation with a standard inguinal incision is used by most surgeons. Others prefer an incision in the longitudinal axes of the inguinal canal, which will make the surgery easier in case of a compromise bowel that needs to be excised. The external inguinal ring is cut. If the hernia contents are present, the hernia sac is opened, and the bowel is inspected. If not compromised, the content is reduced, and the procedure continues in the standard fashion. If the internal ring is still constringing the sac or if the bowel is not viable, the inferior epigastric vessels are ligated and part of the floor of the inguinal canal is opened to enlarge the external ring. Any necrotic bowel must be excised, and an end-to-end anastomosis is performed through the inguinal incision. During closure, the floor of the inguinal canal must be repaired.

If the content of the hernia is reduced before it can be inspected, the surgeon should search for indirect signs of intestinal necrosis, such as foul smell or blood-stained fluid. In dubious cases, a camera can be placed through a port in the umbilicus and if compromised intestine is found, the incision of the umbilicus is enlarged, and the bowel is brought out for repair.

Laparoscopy is gaining ground for the repair of a strangulated hernia and according to some researchers, it presents certain advantages from a technical point of view [99]. It is straightforward that with laparoscopy the incarcerated organ can be easily inspected. It is not necessary to wait a few days for the tissue edema to abate and there is no manipulation of the structures of the cord. Depending on the experience of the surgeon, some prefer to reduce and inspect the bowel through laparoscopy and proceed with herniorrhaphy through the standard inguinal incision [100].

17. Conclusions

Inguinal hernia is the most common surgical disease in children. Although a daily issue in pediatric surgical routine, there are still debates on certain characteristics regarding management decisions and surgical technique. Both open and laparoscopic surgical procedures present their advantages and their risks. However, if we remember the declaration of the Hippocratic oath for the good of the patients according to our ability and judgment, we shall avoid overtreatment and any unnecessary impact on patients and their families. Furthermore, we must have in mind that the future is in minimal invasive surgery. If used with prudence and with a proper learning curve, as technology gets better and more specific, there will be only profit for the health of pediatric patients.