Diaphragmatic Relaxing Incisions for Crural Tension During Hiatal Hernia Repair

Laparoscopic repair of a large hiatal hernia with a widened hiatus is challenging and objective hernia recurrence rates are high. In a recent randomized trial, the recurrence rate exceeded 50% at 5 years after laparoscopic paraesophageal hernia. Tension on the repair of any hernia contributes to an increased risk for recurrence. This was first recognized for inguinal hernias and led to the incorporation of relaxing incisions and tension-free repairs. Subsequently component separation has been adopted to release tension during ventral hernia repair. Logically this concept can be extended to the hiatus for patients with large crural defects where achieving primary approximation of the crural pillars would be difficult or impossible without significant tension. Similar to the tension-free inguinal hernia repair, bridging the crural defect with mesh has been considered. However, bridging with synthetic mesh has been associated with mesh erosion into the esophagus and is ill-advised ( Fig. 28.1 ). Bridging with a biologic mesh is only a temporary solution since the bridged biologic or absorbable material will go away, setting the stage for hernia recurrence. Park et al. proposed using the mobilized falciform ligament to bridge the hiatal defect, but the long-term efficacy of this approach is unknown. In our opinion a better alternative is a relaxing incision in either the right or left diaphragm, and occasionally in both.

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The use of synthetic mesh near the diaphragmatic hiatus can result in erosion of the mesh into the esophagus, as seen in this figure.

The concept of a relaxing incision is to create a defect adjacent to the area of interest that is less critical (muscle or fascia) to allow the principal tissues to come together. In the case of the hiatus, relaxing incisions are ideal since there is available diaphragm on either side. In addition, there is little (if any) downside to making a relaxing incision in the diaphragm. Because there is a pressure differential between the thorax (negative pressure) and the abdomen (positive pressure), all relaxing incisions must be closed. Even small diaphragmatic defects can lead to herniation of abdominal contents into the chest. We routinely close these defects with polytetrafluoroethylene (PTFE), since there is a large experience with this mesh for chest wall and diaphragm reconstruction. Unlike other types of synthetic mesh, the lung does not typically fuse to PTFE mesh, so future thoracic surgical procedures, if needed, will not be made more complex. While there is concern about the use of PTFE mesh in a clean-contaminated case, six of our patients in our published series had a concomitant wedge fundectomy Collis gastroplasty, and no patient developed an infection of the PTFE mesh used in the reconstruction. Unlike ventral hernia repairs with mesh, the use of simple interrupted sutures to sew the PTFE mesh to the edges of the defect with no overlap works well on the diaphragm. This is likely possible because as the mesh contracts, the diaphragm has enough give to accommodate without tearing the stitches out. In fact, the large amount of shrinkage that occurs with PTFE mesh may be beneficial in restoring a more natural contour to the diaphragm over time after a relaxing incision. Absorbable or biologic mesh should be avoided, since it will not permanently repair the defect.

Both right- and left-sided relaxing incisions are relatively straightforward laparoscopic procedures, provided that important landmarks are recognized. In our study, none of our patients suffered complications or paralyzed diaphragms related to the relaxing incisions. Furthermore, it is important to recognize that a wide communication between the abdomen and thorax during a laparoscopic procedure with 15 mm Hg carbon dioxide capnoperitoneum is well tolerated. Small pleural holes can lead to a ball-valve effect and tension pneumothorax, but large openings are not associated with such problems. In fact, large openings of the pleura are standard when we repair large hiatal defects, even without a relaxing incision. This allows the mediastinal space to drain into the right, left, or both pleural cavities once the hernia has been repaired. After the pleura is opened or a relaxing incision has been created, I do not routinely leave drains in the mediastinum or chest unless a lung injury with air leak was created or suspected during the dissection.

Technique for Right-Sided Relaxing Incision

The right-sided relaxing incision is straightforward and adds only 15 to 30 minutes to the overall procedure. It is the preferred release, but the right crus must be at least a centimeter wide to have enough tissue to reconstruct the hiatus following this maneuver. Rarely, but particularly in reoperations, the right crus may be so thin and scarred that there is insufficient room between the edge of the crus and the inferior vena cava to do a right-sided relaxing incision. In these patients, or in the rare patient where a right-sided relaxing incision is insufficient to allow tension-free crural closure, a left-sided relaxing incision is necessary. It is important that the relaxing incision be made anterior to the apex of the hiatus, not posteriorly at the base. Vital structures, such as the aorta and thoracic duct, are near the base, and any incision in the diaphragm should stay above this area. Also, in the vast majority of cases, the base of the hiatus will come together with one or two stitches.

A right relaxing incision is performed by opening the right crus parallel to the inferior vena cava, saving a 3-mm cuff of tissue along the cava to allow a patch to be sewn into place. The right-sided relaxing incision entails a full-thickness incision through the right crus into the right pleural space. It is started in the midportion of the right crus and ends below the anterior crural vein ( Fig. 28.2 ). The diaphragm in this area is quite tendinous, so ultrasonic energy or a hook cautery work well to make the incision on the right side. Typically, the incision only needs to go anteriorly to the level of the crural vein, but if that is insufficient, the crural vein can be ligated and the incision carried further anterior and medially to allow additional release. It is surprising how well this release will allow the right crus to move medially, and in the process leave a gaping defect in the right diaphragm ( Fig. 28.3A ). The only structure of significance to avoid injuring with the right-sided relaxing incision is the intrathoracic vena cava, but this should be anterior and lateral to the incision, if made as described previously. If not used routinely, pledgeted sutures are recommended after a right relaxing incision to minimize the risk that the crural closure sutures pull through the residual right crural pillar. Once the hiatus is reconstructed, the defect created by the relaxing incision is repaired with a permanent mesh. My preference is 1 mm PTFE sewn in with interrupted 3-0 monofilament sutures (see Fig. 28.3B ). I then prefer to reinforce the primary crural closure with absorbable biologic or biosynthetic mesh (see Fig. 28.3C ). The absorbable mesh is secured to the diaphragm using absorbable tacks.