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Table of Contents
REVIEW ARTICLE
Year : 2019  |  Volume : 2  |  Issue : 2  |  Page : 39-43

Current state of repair of large hiatal hernia


Flinders University Discipline of Surgery, Flinders Medical Centre, South Australia 5042, Australia

Date of Submission08-Apr-2019
Date of Acceptance11-Apr-2019
Date of Web Publication10-May-2019

Correspondence Address:
Prof. David I Watson
Flinders University Discipline of Surgery, Room 3D211, Flinders Medical Centre, Bedford Park, South Australia 5042
Australia
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijawhs.ijawhs_12_19

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  Abstract 


Large hiatus hernias are encountered with increasing frequency in aging Western populations. If certain steps are followed, repair can be safely and reliably achieved using laparoscopic approaches. However, surgeons disagree about some key steps, including the use of mesh for repair of the hiatus, lengthening of the esophagus, and the addition of a fundoplication. A narrative review of literature pertinent to laparoscopic repair of large hiatus hernia was undertaken, with priority given to information available from randomized trials. All surgeons agree that the hiatal sac should be fully dissected from the chest to reduce the stomach, and the majority add a fundoplication of some sort. Opinions diverge significantly for the addition of a Collis procedure or the use of mesh. Evidence cited to support these opinions can be prioritized differently by different individuals, and the same evidence is often be cited to support either view. Nevertheless, randomized trials of mesh versus sutured hiatal repair have yielded divergent outcomes, with the more recent studies reporting longer term outcomes failing to support the use of mesh. Surgeons seeking “anatomical perfection” will often add a Collis procedure and are more likely to use mesh. However, the alternative view is that patient satisfaction with the clinical outcome should be prioritized. When this view is taken, a Collis procedure is rarely required. The author concludes that surgeons should aim to keep this operation simple, and an approach which prioritizes careful dissection to protect hiatal structures, followed by sutured repair will deliver a good clinical outcome for most patients.

Keywords: Hiatus hernia, laparoscopic repair, mesh repair


How to cite this article:
Watson DI. Current state of repair of large hiatal hernia. Int J Abdom Wall Hernia Surg 2019;2:39-43

How to cite this URL:
Watson DI. Current state of repair of large hiatal hernia. Int J Abdom Wall Hernia Surg [serial online] 2019 [cited 2021 Apr 20];2:39-43. Available from: http://www.herniasurgeryjournal.org/text.asp?2019/2/2/39/257976




  Introduction Top


Hiatus hernias are common. When small, they can be associated with gastroesophageal reflux, or they can be asymptomatic. Small hernias are not associated with the mechanical symptoms which are associated with the stomach twisting and obstructing, whereas very large hiatus hernias, for example, containing more than 50% of the stomach within the chest, present differently and typically manifest mechanical problems including gastric and/or esophageal obstruction, chest pain, and gastric volvulus. Gastroesophageal reflux is often not a significant issue for patients with very large hernias.

When large series of patients undergoing laparoscopic surgery for gastroesophageal reflux were first reported in the 1990s, only a small proportion of the patients undergoing surgery had a very large hiatus hernia. In the author's early experience of 155 patients, only 10 had a large hiatus hernia.[1] However, across the last two decades, the proportion of patients with a large hiatus hernia undergoing surgery for gastroesophageal reflux and/or hiatus hernia has increased markedly and now exceeds 50% of all cases in many Western centers.[2] This change in workload has followed a reduction in rates of surgery for gastroesophageal reflux, offset by an increase in the incidence of larger hiatus hernias in aging Western populations, as well as a perception that laparoscopic repair of large hiatus hernias is now a safe procedure with a low risk of adverse outcomes.

As case numbers have expanded, surgeons have also critically reviewed their outcomes. Reports of barium meal radiology demonstrating recurrence rates of up to 40% in series reported in the 2000s[3],[4],[5] have encouraged surgeons to question which techniques are appropriate for repair and how to best achieve good outcomes for patients presenting with a large hiatus hernia.


  Risk of Recurrence Top


Laparoscopic techniques for repair of large hiatus hernia were developed in the 1990s, and a consensus was generally achieved by the late 1990s that a technique that focuses on excision of the hernia sac from the chest is required to reliably reduce the stomach back to the abdomen for laparoscopic repair.[6],[7] Initially, most surgeons repaired the hiatus with sutures, placed either posteriorly to the esophagus or both posteriorly and anteriorly. Differences of opinion, however, were evident when considering the issues of esophageal shortening and the need to add an esophageal lengthening (Collis) procedure. Nevertheless, good clinical outcomes have been reported by surgical groups across a range of different techniques.

In 2004 and 2005, studies were published in which barium swallow X-rays were applied to determine objective outcomes at up to 7–8 years follow-up.[4],[5] Radiological recurrence rates of 21%–30% were reported, although most hernia recurrences in these series were small, and their clinical significance was uncertain at that time. A subsequent report from my group followed 115 patients with small radiological recurrences for a further 5 years, and only two required further surgical intervention.[8] This suggested that many of the small radiologically identified hernias in the earlier studies might not be clinically relevant. However, some surgeons have a different view and consider asymptomatic radiological recurrences are at risk of becoming larger and symptomatic recurrences in the future. New approaches to repair have been developed to address this issue, including mesh hiatoplasty.


  Mesh Repair of Hiatus Hernia Top


Building on experience with repair of groin and abdominal wall hernias which demonstrates that the use of mesh to fashion a tension-free repair reduces the risk of hernia recurrence, many surgeons use mesh to reinforce the esophageal hiatus, aiming to reduce hiatus hernia recurrence following laparoscopic repair. Initial reports and case series from mesh advocates report good results, and this has spurred the use of mesh at the hiatus in many parts of the world.[9],[10] However, mesh use can be followed by unique complications and difficulties. Complications include intraoperative damage to surrounding structures when fixing the mesh to the diaphragm, as well as late complications such as mesh erosion.[11] Mesh erosion into the esophageal lumen is a potentially disastrous complication that is difficult to deal with and often only solved by esophagectomy.[12] Other late problems include increased technical difficulty for any revision surgery undertaken following mesh placement.

Early reports of good outcomes following mesh repair have been followed by randomized controlled trials. Five randomized trials have now been reported.[13],[14],[15],[16],[17],[18] To maximize the opportunity for a statistically significant result, these trials all relied on surrogate outcome measures, with radiological or endoscopic evidence of a recurrent hernia (of any size) being the primary outcome in each trial. To date, all of these trials were underpowered to address the clinical outcomes of symptomatic recurrent hernia or surgical revision for hernia recurrence. In addition, the type of mesh and its configuration varied across these trials.

Short-term outcomes at 6–12 months have been reported in all five studies, but with mixed results. Frantzides et al. reported the first trial, in which 72 patients with a large hiatus hernia were enrolled to repair with sutures versus a piece of polytetrafluoroethylene which encircled the esophagus.[13] Barium meal X-ray at 6 months demonstrated a reduction in the hernia recurrence rate from 22% to 0%. Unfortunately, only short-term results have been reported, and longer term outcomes from this trial are unknown. Granderath et al. reported a trial that enrolled 100 patients to sutured repair versus posterior reinforcement of the hiatal repair with posterior onlay of polypropylene mesh during laparoscopic fundoplication for gastroesophageal reflux.[14] Using barium meal X-rays to assess anatomy, this trial demonstrated a reduction in the rate of intrathoracic migration of fundoplication from 26% to 8%. Only short-term outcomes have been reported for this trial. Furthermore, the indication for surgery in this trial was gastroesophageal reflux, not hiatus hernia, with many of the enrolled patients actually not having a large hiatus hernia.

Oelschlager et al. reported a third trial which randomized 108 patients to sutured repair versus a posterior onlay of Surgisis absorbable mesh in patients undergoing repair of a large hiatus hernia.[15] As with the earlier trials, short-term follow-up with barium meal X-ray also showed a reduction in radiological hernia recurrence, defined as 2 cm or more in length, from 24% to 9%. At longer term follow-up of 5 years, however, the earlier difference in recurrence rates disappeared, with recurrence rates of 59% versus 54% reported.[16] Importantly, most radiological recurrences were asymptomatic, and the actual surgical revision rate for recurrent hiatus hernia across the 5-year follow-up period was 3.5% versus 0%.

An Australian multicenter trial enrolled 126 patients with very large hernias containing at least 50% of the stomach.[17] Patients were randomized 1:1:1 to sutured repair versus reinforcement with a posterior onlay of Surgisis or Timesh (lightweight nonabsorbable mesh). At 6-month follow-up, barium meal and endoscopy demonstrated a recurrence of any size in 23% of patients following sutured repair versus 31% following Surgisis and 13% following Timesh. The recurrence difference did not reach statistical significance. When the hernia definition of 2 cm or more in length applied in the Oelschlager was used in this trial, the recurrence rates were 8% versus 6% versus 0%, respectively. However, most patients with recurrences reported no clinical symptoms.[8] More recently, later outcomes from this trial to 5 years have been analyzed, with recurrence rates of 39% following sutured repair, 57% following Surgisis, and 43% following Timesh identified (unpublished data). The late revision rate for recurrent hernia was 3.2%. As with Oelschlager's trial, recurrence rates were not significantly different, and this study also failed to show any advantage for mesh repair.

The fifth trial was recently reported by Oor et al.[18] Seventy-two patients were randomized to sutured repair versus a posterior onlay of Timesh. This trial applied a similar protocol to the Australian study, but evaluating only the best performing mesh arm at 12 months from the Australian trial – Timesh. This trial also failed to demonstrate a difference in radiological recurrence rates (17% vs. 14%) at 12 months.

Collectively, 3 of these 5 randomized trials did not demonstrate any advantage for mesh repair of the hiatus, and both absorbable and nonabsorbable mesh types were evaluated. The first 2 trials did suggest short-term advantages, but both have failed to report longer term follow-up, and the focus of one of these trials was surgery for reflux, not hiatus hernia. After considering the outcomes from the reported randomized trials, it seems reasonable to conclude that the use of mesh remains unproven. Outcomes from further trials are needed before a position of routine mesh repair can be supported by high-quality evidence. Of particular note, absorbable mesh performed poorly in the two trials that evaluated it, and its ongoing use in this context must be questioned. Mesh advocates, however, might draw different conclusions and claim that not all mesh types or configurations were tested in the 5 reported trials, and this viewpoint might be used to justify their use of a different mesh type or mesh configuration. However, a counter argument seems more sensible; until mesh is proven to be better, it requires a leap of faith to believe that alternative mesh types or configurations will not deliver the same outcomes reported across the currently published randomized trials.


  Alternative Strategies for Repair of Large Hiatus Hernia Top


Tension on the gastroesophageal junction due to esophageal shortening has also been proposed as a mechanism for failure of hiatus hernia repair. The Collis gastroplasty procedure is a proposed solution for this problem.[19] There are some potential problems with this approach. First, surgeons working in this area are yet to reach consensus about what constitutes a short esophagus and diagnostic criteria remain uncertain. This has led to divergent approaches, with some surgeons performing a Collis gastroplasty in up to 15% of operations for reflux and hiatus hernia,[20] and others almost never performing this procedure.[21] Second, even if the Collis procedure is performed to lengthen the “esophagus,” it does this by creating a poorly motile tube of gastric wall with acid-secreting mucosa beyond the esophageal segment, and a fundoplication is then placed below this. This creates a scenario which is not physiological, and this might explain the poor outcomes reported following Collis procedures by some surgeons.[22] Finally, creation of a Collis gastroplasty requires division of the upper stomach, generally using a stapling device applied close to the gastroesophageal junction, and this staple line can leak, resulting in significant adverse consequences. These arguments need to be balanced against the risk of a symptomatic recurrent hiatus hernia following repair without a Collis procedure. There are different views about which direction this balance tips toward, and for many surgeons, the arguments for a Collis procedure are not compelling.

Another described approach is a diaphragmatic relaxing incision.[23] This has been recommended as a technique to reduce tension on the hiatal repair. A long incision is made in the lateral left hemidiaphragm to allow the left hiatal pillar to move more medially toward the right pillar for sutured repair. The resulting defect in the left hemidiaphragm is then repaired with a piece of mesh. Advocates report good results from small case series.[23] However, the relaxing incision is quite large, it opens the left pleural cavity widely, and the defect requires repair with a very large piece of mesh. This approach appears more complex than other approaches, and it has been followed by herniation through the left hemidiaphragm due to failure of the mesh repair of the diaphragmatic defect. For these reasons, few surgeons have adopted this approach.


  Addition of a Fundoplication Top


For patients with a large hiatus hernia and symptomatic gastroesophageal reflux, the addition of a fundoplication to hiatus hernia repair is widely accepted as the standard surgical approach. However, many patients presenting with a very large hiatus hernia do not experience reflux symptoms. In these patients, it might be argued that the addition of a fundoplication to repair the hernia is not necessary. However, for several reasons, most surgeons do add a fundoplication of some sort. It has been argued that the creation of a fundoplication buttresses the hiatal repair, and sutures between the fundus and the diaphragm also serve to stabilize the stomach within the abdomen. It has also been suggested that a fundoplication prevents reflux which can manifest following restoration of normal gastric anatomy in a cohort of patients who did not report significant reflux before surgery. Where surgical opinion diverges is about what type of fundoplication to construct. Generally, this will be the same type of wrap that each surgeon uses for standard antireflux surgery. However, a case can be made for minimizing the risk of side effects in patients with a very large hiatus hernia. These patients are up to 2 decades older than those presenting with reflux and often have only mild reflux symptoms. For these reasons, the author's preference is to minimize the risk of side effects in this patient cohort, and a partial fundoplication does minimize that risk.[24],[25]


  Assessing Outcomes – What Matters to Patients? Top


When determining the success of approaches for repair of a very large hiatus hernia, it is necessary to consider what outcomes surgeons and patients are actually aiming for. Is it an excellent clinical outcome, i.e., relief of symptoms, or is it anatomical perfection? Some surgeons regard anything less than anatomical perfection to be failure; i.e., the gastroesophageal junction should always remain below the diaphragm following surgery. However, from the patient's perspective, this might not be correct. Experience from the mesh randomized trials demonstrated that most patients with small recurrent hernias remain symptom free at up to 5-year follow-up and usually did not require further surgery.[8] If a patient originally presented with mechanical issues due to stomach twisting within a large hernia sac (gastric volvulus), and the operation stopped that twisting, then that operation addressed the presenting symptoms. A patient who underwent a sutured repair but then developed a 2-cm sliding hiatus hernia at 5-year follow-up is unlikely to report mechanical symptoms or present with gastric volvulus. From this patient's perspective, the surgery was successful, even though anatomical perfection was not achieved or maintained. This scenario is consistent with most of the recurrences in the mesh trials being asymptomatic, and it accounts for the discrepancy between good clinical outcomes and global outcome measures reported by patients versus high rates of small recurrent hernias in the mesh trials and in earlier case series.[8] Aiming for better anatomical perfection using mesh, adding a Collis procedure, or applying a diaphragmatic releasing incision are unlikely to improve the outcome for most patients, and the 0%–3.5% rate of revisional surgery for recurrent hernia in the trials[16] is probably an acceptable risk, when balanced against the risks that follow more complex surgical approaches.


  The Author's Approach to Very Large Hiatus Hernia Top


The author's experience with more than 700 operations for repair of very large hiatus hernia containing more than 50% of the stomach has led to the conclusion that in the elderly population presenting with this problem, it is best to keep the operation simple. Lengthening the esophagus with a Collis procedure, performing an operation that entails a diaphragmatic relaxing incision, or placing mesh at the hiatus all add complexity, and any subsequent revision operation then becomes even more difficult. Compelling evidence to support the more complex approaches is lacking, and my preference is to accept a 3% reoperation risk after a sutured repair, rather than the risk of complications after a Collis procedure or mesh repair.

To ensure a sound-sutured repair is achieved, attention to certain key steps is advised.[26] First, when dissecting the hernia sac, it is critical to maintain the fascial coverings over both the left and right hiatal pillars, and this is ensured using a diathermy hook to divide the sac 5–10 mm inside the hiatal pillars to ensure that the fascial covering is preserved. Dissection outside this zone uncovers diaphragmatic muscle and increases the size of the hiatal defect that then requires repair. Second, laparoscopic insufflation pressurizes the abdominal cavity and separates the hiatal pillars. This sets up the scenario where the sutured repair can appear to be under tension. Using a liver retractor that provides some abdominal wall lift – for example, the Nathanson retractor, and then reducing the insufflation pressure to 8 mmHg reduces tension on the pillars and facilitates an effective repair with less tension. With this approach, the hiatus can always be closed with sutures, and an effective repair is achieved.


  Conclusions Top


Very large hiatus hernias are increasingly common in aging Western societies, and repair can be reliably performed laparoscopically, with good clinical outcomes in most patients. Surgeons agree that full dissection of the hernia sac is always required, and most add a fundoplication of some sort. However, divergent views remain about whether a sutured repair should be supplemented with an esophageal lengthening procedure or mesh hiatoplasty. Randomized trials assessing mesh repair have yielded conflicting outcomes. As all techniques are reported to deliver good clinical outcomes, a simple sutured technique is still an appropriate approach and remains the author's preferred technique.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
  References Top

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