Jonathan F. Finks
Presentation
A 50-year-old obese man with a large pannus is referred for evaluation of a recurrent right inguinal bulge occurring 5 years following open mesh repair of a right inguinal hernia. He has noticed the bulge for the last several months. Although reducible, the patient has noted increasing discomfort associated with the bulge over the last few weeks. He denies any obstructive symptoms and has had no symptoms on the left side. Physical exam demonstrates some fullness in the right groin, but the exam is limited by the patient’s body habitus.
Differential Diagnosis
The leading diagnosis based on these symptoms is a recurrent right inguinal hernia. Other considerations would include lymphadenopathy; soft tissue mass, such as a lipoma or a sarcoma; and hematoma related to trauma.
Workup
To evaluate for recurrent hernia, the best imaging study is a CT of the abdomen and pelvis, with at least oral contrast. Two sets of images should be obtained: the first using a standard technique and the second with the patient performing a Valsalva maneuver. This test will allow for better identification of hernia contents in the inguinal canal.
Diagnosis and Treatment
In this case, cross-sectional imaging demonstrated a recurrent right inguinal hernia containing nonobstructed loops of small bowel. The left inguinal canal was normal in appearance. Given the symptomatic nature of this hernia, repair is warranted. There are several options for surgical management. An anterior approach would be very difficult and unlikely to produce durable results, given the patient’s body habitus and the presence of previously placed mesh. A preperitoneal approach is preferred in this case because the repair would be done in an unviolated tissue plane. Furthermore, this technique results in coverage of the direct, indirect, and femoral spaces. This could be done using an open preperitoneal technique but would be difficult given the patient’s obesity and large pannus. Similarly, a total extraperitoneal (TEPP) approach would also be hindered by a thick abdominal wall and limited working space due to adipose tissue in the preperitoneal space. In this case, I believe the best technique would be a transabdominal preperitoneal (TAPP) approach. The transabdominal route allows access to the preperitoneal space, while avoiding the thick lower abdominal wall pannus. The TAPP repair is also useful in cases of large scrotal hernias, as these can be more easily reduced from the peritoneal cavity than from the preperitoneal space. The transabdominal approach also allows for assessment of bowel viability in cases of strangulated hernias. Finally, conversion to TAPP repair may also be required during an attempted TEPP repair if, for example, the peritoneum is violated while attempting to develop the preperitoneal space with a balloon dissector. This latter scenario often occurs in patients with lower abdominal incisions (e.g., Pfannenstiel).
Surgical Approach
In essence, the TAPP procedure for inguinal hernia repair involves entry into the preperitoneal space by incision of the lower abdominal wall peritoneum from inside the peritoneal cavity (Table 1). Once in the preperitoneal space, the hernia sac is dissected free from the cord structures and reduced from within the deep inguinal ring (indirect hernia), Hesselbach’s triangle (direct hernia), and/or the femoral space (femoral hernia). Once the hernia contents have been reduced, the peritoneum is dissected well off of the cord structures to make room for placement of the mesh. Mesh is then placed such that it adequately covers the direct, indirect, and femoral spaces. The peritoneum is then secured up to the abdominal wall to cover the mesh.
TABLE 1. Key Technical Steps and Potential Pitfalls
The procedure is performed under general anesthesia with the patient supine, both arms tucked to the side, in slight Trendelenburg position. A Foley catheter is inserted to decompress the bladder. Access to the peritoneum is obtained using a closed (Veress) or an open (Hasson) technique, and pneumoperitoneum is established. The surgeon stands on the side opposite the hernia, with the assistant on the ipsilateral side (Figure 1). An 11-mm trocar is placed above the umbilicus in the midline for placement of the laparoscope and later insertion of the mesh into the peritoneal cavity. Many surgeons prefer to work through ports on both sides of the midline so as to effect proper triangulation (Figure 1). However, in the obese individual, the surgeons’ working ports (both 5-mm ports) should both be on the side contralateral to the hernia, usually on either side of the midclavicular line and below the level of the umbilicus. In some cases, an additional 5-mm assistant’s port may be placed on the ipsilateral side, at the midclavicular line above the level of the umbilicus. In the case of bilateral inguinal hernia repair, the working trocars are generally placed at or above the level of the umbilicus. A 10-mm 30° laparoscope is employed, although some surgeons prefer a 0° laparoscope in nonobese patients.
FIGURE 1 • Operating room setup and trocar placement for a TAPP hernia repair. (From Soper, Swanstrom, Eubanks. Mastery of Endoscopic and Laparoscopic Surgery. 3rd ed. Lippincott Williams and Wilkins, 2009, Figure 53-13.)
The procedure begins with an inspection of the lower abdominal wall on both sides. Figure 2 shows the anatomy and landmarks in the right lower abdomen. The median umbilical ligaments and epigastric vessels should be identified on either side of the bladder. Any obvious hernia defects should be identified, although some of these may not be apparent until the peritoneum is taken down. Indirect hernias are located lateral to the inferior epigastric vessels. Direct hernias occur through Hesselbach’s triangle, bordered laterally by the inferior epigastric vessels, medially by lateral edge of the rectus muscle, and inferiorly by the inguinal ligament. Femoral hernias occur through the femoral space, bordered laterally by the femoral vein, posteriorly by Cooper’s ligament, and anteriorly by the inguinal ligament.
FIGURE 2 • Laparoscopic view and anatomy of right lower abdominal wall seen during TAPP hernia repair. (From Soper, Swanstrom, Eubanks. Mastery of Endoscopic and Laparoscopic Surgery. 3rd ed. Lippincott Williams and Wilkins, 2009, Figure 53-14.)
The preperitoneal space is then developed beginning with an incision in the peritoneum using electrocautery. The incision begins vertically along the ipsilateral median umbilical ligament down to its root. The incision is carried transversely above the level of the hernia defects, across to the anterior superior iliac spine (Figure 3). In cases of a bilateral inguinal hernia, a mirror incision is made on the opposite side. Separate dissections and pieces of mesh are used to repair bilateral hernias. Blunt and sharp dissection with electrocautery is then used to develop the preperitoneal space, staying close to the peritoneum. This dissection begins lateral to the cord structures, in Bogros’ space, advances medially toward the retropubic space, and extends proximally to expose the femoral vessels, psoas muscle, and retroperitoneum (Figure 3). Medially, the bladder is carefully dissected off of the anterior abdominal wall, exposing the symphysis pubis and Cooper’s ligament. Care must be taken not to injure corona mortis, which refers to the venous connection between the inferior epigastric and obturator veins. This structure courses inferiorly along the lateral aspect of Cooper’s ligament and, because of its location on the pubic bone, can be difficult to control if lacerated or avulsed.
FIGURE 3 • Peritoneal incision (solid line) and extent of dissection (dashed line) in a left-sided TAPP hernia repair. (From Soper, Swanstrom, Eubanks. Mastery of Endoscopic and Laparoscopic Surgery. 3rd ed. Lippincott Williams and Wilkins, 2009, Figure 53-1.)
An assessment for femoral and direct hernia defects occurs during the medial dissection. Careful attention is paid to identify the critical structures: inferior epigastric vessels, Cooper’s ligament, and the femoral vein. Direct and femoral hernias may contain only preperitoneal fat or they may contain a hernia sac. It is not uncommon for direct hernias to contain the urinary bladder. The hernia contents are reduced with gentle blunt dissection. With a direct hernia, there is usually a clear transition between the transversalis fascia and the hernia sac. These structures can often be separated by applying cephalad and posterior retraction of the sac and anterior and caudad retraction of the transversalis fascia. In the setting of a large direct defect, large seromas may develop. To help minimize the risk for seroma formation, the transversalis fascia may be reduced from within Hesselbach’s triangle and tacked to Cooper’s ligament. When reducing femoral hernias, care must be taken to carefully delineate between hernia contents and the fat and lymphatic tissue intimately associated with the femoral vein. Injudicious dissection can lead to injury to the femoral vein. The medial dissection may also reveal an obturator hernia, located posterior to Cooper’s ligament through the obturator foramen. These are also reduced by blunt dissection and may require an additional medially placed mesh to cover the defect.
An indirect hernia is identified during the lateral dissection. The hernia sac is bluntly dissected away from the underlying spermatic cord structures, namely the vas deferens and the testicular vessels. The sac must be dissected free from the cord structures prior to reduction of the sac from within the deep inguinal ring to avoid inadvertent laceration or transection of the vas deferens or testicular vessels. The hernia sac is then reduced by application of cephalad and posterior retraction on the hernia sac, with anterior and caudad retraction of the transversalis fascia. We do not employ cautery during this dissection, especially in the space lateral to the cord structures, to avoid injury to the genital branch of the genitofemoral nerve, which courses anterior to the psoas muscle in the pelvis and passes through the inguinal canal along with the cord in the lateral bundle of the cremasteric fascia.
Care must be taken to ensure that the hernia sac remains free from the cord structures during this entire process, particularly in the setting of a large scrotal sac. If the peritoneal sac is very large and cannot be easily reduced, it may be transected, with the distal aspect allowed to retract into the scrotum. The proximal aspect of the sac must then be secured during reperitonealization following the mesh repair to prevent bowel adhesions to the mesh. Transection of the sac is safe but may lead to development of a hydrocele in some cases. Preperitoneal fat within the deep inguinal ring (cord lipomas) should be completely reduced from that space in order to prevent the patient’s sensation of a persistent bulge following hernia repair.
Once the hernia sac has been reduced, the peritoneum is dissected off of the cord structures in a cephalad direction. Adequate parietalization of the cord is essential, as it prevents peritoneum from slipping underneath the bottom edge of the mesh, which leads to lateral recurrences. Similarly, herniated preperitoneal fat must also be dissected well off of the cord so that it cannot slip beneath the mesh. This dissection continues cephalad to the level of the anterior superior iliac spine and laterally to the iliac wing, allowing for exposure of the psoas muscle. Medially, this continues to the transition to the urinary bladder, which is then itself dissected off of Cooper’s ligament and the pubis in order to clear a space for placement of the mesh. Gentle medial retraction on the bladder allows for better delineation between prevesicular fat and fat associated with the femoral vein and helps reduce the risk of inadvertent injury to the vein.
Once hemostasis has been ensured, the next step involves placement of a large piece of nonabsorbable mesh. We employ an anatomically contoured, lightweight, woven polypropylene mesh that is 10 cm in height by 16 cm in width. The mesh must be large enough to cover the direct, indirect, and femoral spaces (myopectineal orifice) and the posterior aspect of Cooper’s ligament. In the case of bilateral hernias, two pieces of mesh are used. The mesh is rolled and inserted into the abdomen through the 10-mm port. It is inserted into the preperitoneal space and unrolled such that the inferior aspect is draped over the cord structures and psoas muscle laterally and Cooper’s ligament and pubic symphysis medially. The superior aspect of mesh then covers the anterior abdominal wall above the level of the iliopubic tract, including the inferior epigastric vessels and the rectus muscle medially. We tack the mesh medially to Cooper’s ligament with a single 5-mm spiral tack to prevent the mesh from sliding and will tack to the rectus muscle in cases of a large direct hernia to prevent the mesh from herniating through the defect. We avoid any tack placement laterally to prevent injury to the ilioinguinal and iliohypogastric nerves.
Once the mesh has been placed, the peritoneum is closed. This is facilitated by reducing the pneumoperitoneum pressure as low as possible, while still permitting adequate visualization. The entire peritoneum must be secured and the mesh covered to prevent bowel adhesions to the mesh or incarceration of a bowel loop within the preperitoneal space. This can be accomplished using spiral tacks, suture, or a combination of these.
Special Intraoperative Considerations
In general, it is easy to get disoriented during laparoscopic inguinal hernia repairs, whether done as a TEPP or a TAPP procedure, and this can lead to disastrous consequences. In the setting of a large indirect hernia sac, particularly in an obese patient, it can be difficult to identify the cord structures and this can lead to dissection in the deeper “triangle of doom” with inadvertent injury to the femoral artery or vein. It is worthwhile to periodically identify known landmarks, such as Cooper’s ligament and the symphysis pubis as well as the inferior epigastric vessels. Such periodic reorienting is often very helpful in keeping the dissection in the proper plane. In the event of a femoral vein injury, conversion to open will most likely be required. First, however, the surgeon should increase the pneumoperitoneum pressure to 25 mm of mercury or higher as necessary to help tamponade the bleeding. Direct pressure with a Raytec opened completely and inserted through the 10-mm trocar will allow for direct compression of the vessel. These two maneuvers should provide adequate hemostasis and time for a deliberate conversion to open with all members of the surgical team prepared and ready.
TAKE HOME POINTS
· The TAPP approach should be considered for patients with an indication for a preperitoneal repair (e.g. bilateral or recurrent inguinal or femoral hernia) in whom a TEPP approach is not feasible (e.g. due to obesity, previous pfannenstiel incision, or inadvertent peritoneal entry during access in an attempted TEPP repair).
· The right and left preperitoneal spaces should be dissected separately and 2 pieces of mesh used in cases of bilateral hernias to reduce the risk of recurrent hernia.
· Initial dissection in the preperitoneal space should remain close to the peritoneum to avoid inadvertent injury to the femoral vessels.
· Adequate closure of the peritoneum after hernia repair is essential to prevent adhesions between bowel and mesh and to prevent internal herniation of bowel loops within the preperitoneal space.
SUGGESTED READINGS
Felix E. Causes of recurrence after laparoscopic hernioplasty. A multicenter study. Surg Endosc. 1998;12(3):226–231.
Lovisetto F. Laparoscopic transabdominal preperitoneal (TAPP) hernia repair: surgical phases and complications. Surg Endosc. 2007;21(4):646–652.
McCormack K. Laparoscopic techniques versus open techniques for inguinal hernia repair. Cochrane Database Syst Rev. 2003;(1):CD001785.
Rebuffat C. Laparoscopic repair of strangulated hernias. Surg Endosc. 2006;20(1):131–134.
Rosenberger RJ. The cutaneous nerves encountered during laparoscopic repair of inguinal hernia: new anatomical findings for the surgeon. Surg Endosc. 2000;14(8):731–735.