Ventral hernia and obesity: is there a consensus?

Introduction

Abdominal wall hernia repair is one of the commonest surgical procedures performed in surgical practice. For the purpose of the review, ventral hernia and incisional hernia will be referred to as abdominal wall hernia. Today surgical repair of abdominal wall hernia using a mesh is considered gold standard and universally accepted, except for very small defects. Over the years, surgeons and researchers have worked relentlessly to improve our understanding of hernia formation and its management. This has led to a reasonable standardisation of surgical technique. Our focus has now shifted towards improvement in mesh technology and modification of patient factors whereby we can reduce complications mainly recurrence.

Abdominal wall hernia by definition is a defect in the abdominal wall and may present at a variety of sites. In United States alone, 350,000 abdominal wall hernia repairs are performed annually (1). In United Kingdom, approximately 600,000 patients undergo laparotomy annually for some abdominal pathology. Subsequently, 10–20% of these will develop an incisional hernia, roughly amounting to 60,000 to 120,000 patients every year (2,3).

Obesity is defined as a body mass index (BMI) ≥30 kg/m² and morbid obesity—also termed class III obesity as BMI ≥40 kg/m². In Asian individuals, they are defined as BMI ≥27.5 and ≥37.5 kg/m² respectively. Obesity has gained epidemic proportions, and its incidence predicted to rise even further in young individuals. Even more concerning is that the prevalence of severe obesity is rising much exponentially when compared to moderate obesity (4). In United States alone, the prevalence of obesity is 35% and 40.4% in males and females respectively (5). Prevalence of obesity is also on the rise in Asians. A health survey from Singapore found the prevalence of obesity to be 24% in Malaysians, 16.9% in Indians and 7.9% in Chinese individuals (6). The longstanding consequence of severe obesity on abdominal wall is hernia formation and panniculus morbidus (7). Obesity itself is a risk factor for development of primary as well as incisional hernia (8). Obese individuals are also more likely to have comorbidities, which significantly increase the peri-operative risks (5,9). Obese patients are at increased risk for re-admissions, blood transfusion, hospital acquired infections, wound healing issues and surgical site infections (SSIs) (10,11).

In obese patients, AWHR is challenging irrespective of the hernia site and defect size (9). In fact, AWHR in patients with high BMI are associated with wound complications rates of 48.7% and recurrence rates of 41.7% (12-14). Many obese patients will have a predominant “abdominal obesity” or a centralised distribution of subcutaneous fat. This is particularly challenging, and hence technical modifications are needed during surgery to limit wound related complications (15,16). There is paucity of data regarding comparative outcomes of AWHR in obese and non-obese patients. The limited data available, has significant heterogeneity within patient groups, the hernia defect size and location, follow up and the population (13,17-20). The large prevalence of hernia and its associated morbidity, the surgical costs, procedure related morbidity and loss of work hours adds a significant strain to any healthcare system, in addition to the impact on patient quality of life (21,22).

Hernia and obesity—the dilemma:

While dealing with obese patients with hernia, surgeons will frequently encounter these difficult scenarios:

• Patient referred for bariatric surgery and found to have a hernia. Here, patients’ primary concern is the weight and its associated problems. Hernia may be asymptomatic or a secondary issue.
• Patient primarily referred for abdominal wall hernia but is a suitable candidate to consider bariatric surgery.

In both the scenarios, surgeons and the weight management team are faced with a common dilemma:

• Is bariatric surgery needed?
• Do we offer the patient concomitant weight loss and hernia repair surgery?
• Type of hernia repair?
• Whether to use mesh or not?
• If patient undergo only weight loss surgery—when is the optimal time to consider a hernia repair?
• If patient is unwilling for weight loss surgery, do we repair the hernia first?
• What is the optimal pre-operative weight loss before planning a hernia repair?
• What if the patient fails to lose weight?

Impact of obesity on hernia

Obesity is an independent risk factor for both primary and incisional hernia formation (8). Obesity also leads to an increased risk of perioperative complications and recurrence rates. Delayed wound healing, impaired pulmonary function, suboptimal control of comorbidities particularly diabetes and a higher intra-abdominal pressure are common reasons for hernia formation as well as recurrence (23). Mavros et al. reported higher mesh infection rates in obese patients following open ventral hernia repair (24).

In obese patients with hernia always expect the abdominal wall defect size to be larger than what is clinically apparent. Moreno-Egea et al. in their study demonstrated the correlation between obesity and hernia defect size. In their study, patients with BMI ≥30 kg/m², 35.1% of patients had a defect larger than 10 cm. However, in patients with defect size between 10–12 cm, 60% patients had a BMI ≥30 kg/m². When defect was more than 12 cm, 73.5% patients had ≥30 kg/m² (25). In the same study, they followed up patients of laparoscopic mesh repair of abdominal wall hernia. In patients with defect <10 cm the recurrence rate was 0.4%, defects between 10–12 cm it was 20% and 41.2% in patients with defect >12 cm. Similarly, on comparing the BMI between patients with recurrence and non-recurrence group, they reported a mean BMI of 36.3±6.3 and 29.5±5.9 kg/m² respectively. While 90% patients in the recurrence group had BMI ≥30 kg/m², it was only 37.9% in the non-recurrence group. This difference was found to be significant. Similarly, the mean defect size was 14.4 vs. 7.9 cm respectively in recurrence and non-recurrence group (P<0.001).

Operative approach for abdominal wall hernia repair in obese patients

The surgical approach for abdominal wall hernia depends upon multiple variables. Patient age, comorbidities, fitness for general anaesthesia, location of hernia, defect size, contents of hernia and loss of domain are some factors to be considered (Figure 1). The nature of surgery whether elective or emergency will also influence the decision-making process. In obese patients with hernia, panniculus morbidus, impaired pulmonary function, higher intra-abdominal pressure, skin infections, delayed wound healing and obesity associated comorbidity need to be considered.

Figure 1 Complex abdominal wall hernia in morbidly obese.

Laparoscopic repair

A meta-analysis of multiple randomised controlled trials, comparing laparoscopic abdominal wall hernia repair with open repair showed significant reduction in wound infection rates, reduced mesh removal rates with laparoscopy (26). They also reported that laparoscopic repair was safe and feasible with fewer complications, shorter hospital stays and operative times, although the post-operative pain and recurrence rates were similar to open repair. A Cochrane database review by Sauerland et al. reported significant lower local wound infection rates of 3.1% vs. 13.4% in laparoscopic group when compared to open repair (27). In the event of a local infection, they reported a significantly lower mesh removal rates in laparoscopic group 0.7% vs. open group 3.5%. Pierce et al. in their analysis of pooled data comparing 4,582 laparoscopic and 758 open abdominal wall hernia repairs (28). They reported a significantly higher wound complication rate of 16.8% in open technique, as compared to 3.8% in laparoscopic group. Laparoscopy by reducing the wound complication rates offers an added advantage in obese individuals who have a higher risk of wound related complications. A meta-analysis by Mavros et al. which analysed multiple cohort studies, demonstrated higher mesh infection rates after open ventral hernia repair in obese patients (24). Obese patients with incisional hernia, the surgeon should always expect a larger hernia defect as explained previously (25).

Novitsky et al. from US studied patients undergoing laparoscopic ventral hernia repair (LVHR). Total 163 obese patients who underwent LVHR over 5 years were evaluated. 8 patients in this group were super obese with a BMI ≥50 kg/m², with the highest BMI of 67 kg/m². They demonstrated an overall complication rate of 12.3%, with seroma being the most common. Mean hospital stay was 2.6 days and recurrence documented in 2 pts (5.5%). They concluded that LVHR in obese patients with complex hernias is safe and feasible with minimal peri-operative morbidity, low rate of conversion to laparotomy with a success rate of 94.5%. These results suggested an improved efficacy with LVHR when compared to historical outcomes among control patients subjected to an open repair (29). Similarly, Marx et al. demonstrated a recurrence rate of 3.8% at a mean follow up of 18 months in patients with BMI >35 kg/m² (30). In another study, Raftopoulos et al. followed up a heterogeneous group of 27 LVHR patients with a mean BMI of 46.9 kg/m² (31). The patients had a wide variety of case mix from primary, incisional, recurrent hernia as well as patients subjected to concomitant laparoscopic Roux-en-Y gastric bypass (LYRGB) and hernia repair. An intra-peritoneal mesh was used in all cases and fixed to the abdominal wall with transfascial sutures and circumferential tackers. A 4 cm overlap was achieved in all cases. Incidence of 30-day complications was 25.9% which included wound infection, pneumonia, small bowel obstruction, bladder injury. Recurrence rate was 18.5% at a mean follow up of 15 months.

The degree of obesity has a significant effect on the recurrence rate. Bower et al. in their study of 100 consecutive LVHR demonstrated 73% complications in patients with BMI >30 kg/m². All the recurrences were seen in obese patients only (32). Similarly, another study demonstrated a recurrence rate of 2.9% in normal BMI patients vs. 8.3% in those with BMI ≥40 kg/m² (16). Both these studies reported a shorter time for hernia recurrence when BMI was high.

Open repair

A National database review of inpatients and discharge records from US investigated the outcomes of LVHR with open repair in 47,000 obese patients (33). They concluded that LVHR was associated with shorter hospital stay, reduced hospitalisation cost, lesser wound complications, pulmonary complications, unintentional injury to viscera.

Krpata et al. reported a series of open retro-muscular incisional hernia repair with 63% patients having a BMI >30 kg/m² (34). At a mean follow up of 17 months, they reported an overall wound complication rate of 16% and recurrence rate of 5%. In 2008, Moore et al. in their series of open retro-muscular hernia repair, documented a recurrence rate of 5.5% and wound complications in 18.8% patients. The mean follow-up was 50 months (35). In another series of 131 open umbilical hernia repair, patients with normal BMI had a recurrence rate of 5% vs. 18% in patients with BMI >25 kg/m² at 32 months mean follow-up (36).

Though laparoscopy may be preferred in obese, certain scenarios may warrant a surgeon to consider open mesh repair. Emergency surgery for hernia related complications, very large defects with need for component separation techniques, loss of domain and the need for resection of panniculus are few scenarios, although with advanced skills and experience laparoscopy may still be attempted on a case to case basis.

Incisional hernia repair with resection of panniculus

A commonly performed procedure during open hernia repair, panniculectomy may be needed to improve cosmesis, remove redundant and dystrophic skin or hernia sac. Excising the panniculus may also be needed to remove the pendulous effect on the incision. Panniculectomy can be challenging in severely obese patients. In their series of 10 patients with morbid obesity subjected to hernia repair and panniculectomy, Okusanya et al. reported a recurrence rate of 10% and a 40% overall wound complication rate at mean follow-up of 12 months (37). Warren et al. reviewed patients subjected to open incisional hernia repair with or without panniculectomy. In both the groups, mean BMI was 34.3 kg/m². Both groups had similar wound infection rates and hernia recurrence rate, suggesting that addition of panniculectomy did not worsen the wound related complications (38).

In a randomised controlled trial, Moreno-Egea et al. compared incisional hernia repair patients with or without abdominoplasty. Although the operative times were longer in the abdominoplasty group, no differences were found in early and delayed morbidity. In fact, patients who underwent hernia repair and a concomitant abdominoplasty, reported improved quality of life scores (39).

Concomitant laparoscopic hernia repair and bariatric or metabolic surgery

When surgeons are confronted with an obese patient with abdominal wall hernia, the dilemma faced is—what do we treat first? Obesity, hernia or both. The challenge may be compounded if the patient has undergone a bariatric surgery with significant weight regain and also developed a hernia. Due to paucity of data in literature, we lack a consensus of the best way to manage these patients. Most surgeons or specialised centres will develop departmental protocols or customized approach based on hernia symptoms and characteristics, patients weight loss goals, BMI and associated comorbidities (40). Depending upon surgeon experience and if hernia is suitable for laparoscopic repair, bariatric surgery and concomitant hernia repair may be attempted laparoscopically.

Eid et al. was the first to report a series of 85 patients with abdominal wall hernia and planned for LRYGB (41). Following LRYGB, 55 patients underwent primary suture repair, biological mesh was used in 12 and in 14 patients, hernia repair was deferred. All patients were followed up for minimum 6 months. They reported a recurrence rate of 22% in primary suture repair group, none in mesh repair group during a mean follow up of 26 months. Out of the 14 patients in whom hernia repair was deferred, 38% developed intestinal obstruction due to hernia incarceration. Based on the findings, they concluded that mesh repair is preferable in obese patients with hernia and deferring hernia repair may lead to hernia related complications.

Our prime concern while planning concomitant hernia repair and bariatric surgery is the fear of mesh contamination, though a number of retrospective case series have demonstrated safety of mesh implantation during stapled bariatric surgery. In a series, Datta et al. repaired 26 abdominal wall hernia identified during LRYGB and repaired with a polypropylene mesh. They did not report any mesh infections (42). Similarly, Schuster et al. did not report any mesh infections in patients subjected to combined LRYGB and ventral hernia repair with polyester or polypropylene mesh (43). Chan et al. in their series of 45 patients subjected to simultaneous laparoscopic bariatric surgery and ventral hernia repair with polypropylene or polytetrafluoroethylene mesh (44). They reported 2 patients with mesh infection, both managed conservatively without need to explant mesh. Similar results and outcomes were reported by other studies, documenting safety of implantation of mesh simultaneously with wide variety of bariatric or metabolic surgery (45,46). In one study, Sharma et al. followed up 159 patients who had undergone combined bariatric surgery and ventral hernia repair (47). Out of 159, 44 patients underwent mesh repair with biological or synthetic mesh and 115 offered primary suture repair. They reported wound infection in 9 patients, no mesh infections and 3 patients with recurrence. They suggested that primary suture repair if feasible, may be acceptable in selected cases during bariatric surgery.

In 2015, Spaniolas et al. reviewed 17,000 LYRGB and sleeve gastrectomy patients from the National Surgical Quality Improvement Program (NSQIP). In these, 503 patients were subjected to concomitant ventral hernia repair. While these patients had a slightly higher odds ratio of SSI, no significant differences were found in the 30-day morbidity and mortality rates (48). In the absence of any randomised trials or long-term prospective studies, it is very difficult to reach any definitive conclusion while managing these complex groups of patients.

Bariatric surgery followed by hernia repair at a later date

An upfront bariatric surgery for weight loss as a first stage surgery, followed by hernia repair at a later date although sounds feasible, but may not be practical clinically. The risks associated with not addressing the hernia at the time of bariatric surgery are documented (41). Also, convincing a patient who has primarily come for a non-bariatric surgery, to consider weight loss surgery as first stage, may not be acceptable to the patient. Patient counselling with regards to additional costs of bariatric surgery and its associated morbidity and mortality are paramount. In the 18 patients reported by Hidalgo et al. who were subjected to sleeve gastrectomy prior to a non-bariatric procedure, only 1 had an abdominal wall hernia (49). The mean BMI reduced from 45 to 36 kg/m², with minimal morbidity. Similarly, Newcomb et al. in his retrospective review of 27 patients who were offered gastric bypass as a first stage surgery prior to hernia repair. Twenty-two patients underwent open gastric bypass and 5 LRYGB. They documented a mean BMI reduction from 51 to 33 kg/m² over an average period of 1.3 years. Only one patient needed emergency surgery while waiting for elective hernia repair (50). Further randomised trials incorporating this strategy are needed before deriving any conclusions.

Other weight loss modalities before elective hernia repair

Though weight loss is desirable in obese patients prior to elective hernia repair, not all patients may be suitable candidates to offer weight loss surgery either concomitant or as a first stage. Patients with large defect hernia, incarcerated hernias with bowel as contents, loss of domain, extensive bowel adhesions, overlying skin issues e.g., ulceration, fungal infections etc., recurrent hernias with previous mesh are complex scenarios, while some patients may not be keen to consider bariatric surgery. Hence in order to achieve weight loss possible management options are:

• Medically supervised low-calorie diets;
• Pharmacotherapy;
• Intra-gastric balloon therapy.

The success rates of any such strategy are yet to be defined. Patient compliance is a major deterrent. Yet in patients who are unfit or unwilling for weight loss surgery, it may be worthwhile attempting a weight loss with one of the above non-surgical modalities.

Guidelines on obesity and abdominal wall hernia management

The International Endo-hernia Society Guidelines (IEHS) (51) recommended that:

• Laparoscopy should be the preferred approach for managing ventral and incisional hernia in obese patients due to lower wound infection and complication rates.
• In obese patients defect size is significantly larger.
• In obese patients with defect larger than 8–10 cm, use more overlap, greater mesh fixation and defect closure.

Hence in patients with BMI >30 kg/m² particularly those with defects more than 8–10 cm anticipate larger defect and possible higher recurrence rates. As surgeons we need to make technical modifications like more extensive overlap of the defect with mesh, stronger mesh fixation and defect closure.

Similarly, the European Association for Endoscopic Surgery (EAES) and European Hernia Society (EHS) collaboration guidelines on ventral and incisional hernias stated that laparoscopic repair offers an acceptable alternative to open repair and is recommended in obese patients with ventral and incisional hernias by virtue of shorter hospital stay and reduced wound complications (52).

Recently, the American Society for Metabolic and Bariatric Surgery and the American Hernia Society consensus guideline on bariatric surgery and hernia surgery recommended that (53):

• Obesity is a risk factor for development of primary as well as incisional hernia;
• Abdominal wall hernia in obese are more likely to present with complications e.g., obstruction, strangulation;
• Obesity is risk factor for hernia recurrence as well as post-operative complications;
• In severely obese patients with hernia amenable to laparoscopic repair, concurrent hernia repair and bariatric surgery may be safe with good short-term outcomes;
• There is lack of evidence, with regards to the safety of use of mesh in the setting of combined bariatric surgery and hernia repair;
• Weight loss prior to hernia repair in obese is desirable and will improve outcomes.

Conclusions

Abdominal wall hernia is commonly associated with obesity. Laparoscopic repair is preferred over open repair in obese patients. Similarly, mesh repair is better than primary repair in obese patients. There is insufficient evidence to conclude the best management strategy for obese patients with abdominal wall hernia who are suitable candidates for bariatric surgery. While weight loss prior to hernia repair is desirable and known to improve outcomes, there is paucity of data to conclude the best timing for hernia repair in patients subjected to bariatric surgery. Use of prosthesis during bariatric surgery or deferring a hernia repair carries its own set of complications. In the authors’ opinion, until further randomised control trials can be performed, an individualised case approach based upon patient symptoms, hernia characteristics, type of bariatric surgery and patient preferences needs to be considered.

Acknowledgments

Funding: None.

Footnote

Provenance and Peer Review: This article was commissioned by the editorial office, Annals of Laparoscopic and Endoscopic Surgery for the series “Ventral Hernia”. The article has undergone external peer review.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/ales.2019.01.07). The series “Ventral Hernia” was commissioned by the editorial office without any funding or sponsorship. DL served as the unpaid Guest Editor of the series. The authors have no other conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Poulose BK, Shelton J, Phillips S, et al. Epidemiology and cost of ventral hernia repair: making the case for hernia research. Hernia 2012;16:179-83. [Crossref] [PubMed]
2. Mudge M, Hughes LE. Incisional hernia: a 10 year prospective study of incidence and attitudes. Br J Surg 1985;72:70-1. [Crossref] [PubMed]
3. Cassar K, Munro A. Surgical treatment of incisional hernia. Br J Surg 2002;89:534-45. [Crossref] [PubMed]
4. Sturm R. Increases in morbid obesity in the USA: 2000-2005. Public Health 2007;121:492-6. [Crossref] [PubMed]
5. Flegal KM, Kruszon-Moran D, Carroll MD, et al. Trends in obesity among adults in the United States, 2005 to 2014. JAMA 2016;315:2284-91. [Crossref] [PubMed]
6. Ministry of Health. National Health Survey 2010. Epidemiology and Disease Control Division, Ministry of Health: Singapore, 2011.
7. Friedrich JB, Petrov RV, Askay SA, et al. Resection of panniculus morbidus: a salvage procedure with a steep learning curve. Plast Reconstr Surg 2008;121:108-14. [Crossref] [PubMed]
8. Sugerman HJ, Kellum JM Jr, Reines HD, et al. Greater risk of incisional hernia with morbidly obese than steroid-dependent patients and low recurrence with prefascial polypropylene mesh. Am J Surg 1996;171:80-4. [Crossref] [PubMed]
9. Ford ES, Maynard LM, Li C. Trends in mean waist circumference and abdominal obesity among US adults, 1999-2012. JAMA 2014;312:1151-3. [Crossref] [PubMed]
10. Manilich E, Vogel JD, Kiran RP, et al. Key factors associated with postoperative complications in patients undergoing colorectal surgery. Dis Colon Rectum 2013;56:64-71. [Crossref] [PubMed]
11. Wick EC, Hirose K, Shore AD, et al. Surgical site infections and cost in obese patients undergoing colorectal surgery. Arch Surg 2011;146:1068-72. [Crossref] [PubMed]
12. Kaoutzanis C, Leichtle SW, Mouawad NJ, et al. Risk factors for postoperative wound infections and prolonged hospitalization after ventral/incisional hernia repair. Hernia 2015;19:113-23. [Crossref] [PubMed]
13. Rosen MJ, Aydogdu K, Grafmiller K, et al. A multidisciplinary approach to medical weight loss prior to complex abdominal wall reconstruction: Is it Feasible? J Gastrointest Surg 2015;19:1399-406. [Crossref] [PubMed]
14. Regner JL, Mrdutt MM, Munoz-Maldonado Y. Tailoring surgical approach for elective ventral hernia repair based on obesity and National Surgical Quality Improvement Program outcomes. Am J Surg 2015;210:1024-9. [Crossref] [PubMed]
15. Fekkes JF, Velanovich V. Amelioration of the effects of obesity on short-term postoperative complications of laparoscopic and open ventral hernia repair. Surg Laparosc Endosc Percutan Tech 2015;25:151-7. [Crossref] [PubMed]
16. Tsereteli Z, Pryor BA, Heniford BT, et al. Laparoscopic ventral hernia repair (LVHR) in morbidly obese patients. Hernia 2008;12:233-8. [Crossref] [PubMed]
17. Desai KA, Razavi SA, Hart AM, et al. The Effect of BMI on outcomes following complex abdominal wall reconstructions. Ann Plast Surg 2016;76:S295-7. [Crossref] [PubMed]
18. Mullen JT, Moorman DW, Davenport DL. The obesity paradox: body mass index and outcomes in patients undergoing nonbariatric general surgery. Ann Surg 2009;250:166-72. [Crossref] [PubMed]
19. Doyle SL, Lysaght J, Reynolds JV. Obesity and post-operative complications in patients undergoing non-bariatric surgery. Obes Rev 2010;11:875-86. [Crossref] [PubMed]
20. Ching SS, Sarela AI, Dexter SP, et al. Comparison of early outcomes for laparoscopic ventral hernia repair between nonobese and morbidly obese patient populations. Surg Endosc 2008;22:2244-50. [Crossref] [PubMed]
21. Merkow RP, Ju MH, Chung JW, et al. Underlying reasons associated with hospital readmission following surgery in the United States. JAMA 2015;313:483-95. [Crossref] [PubMed]
22. Rutkow IM. Demographic and socioeconomic aspects of hernia repair in the United States in 2003. Surg Clin North Am 2003;83:1045-51. [Crossref] [PubMed]
23. LeBlanc KA, Booth WV. Laparoscopic repair of incisional abdominal hernias using expanded polytetrafluoroethylene: preliminary findings. Surg Laparosc Endosc 1993;3:39-41. [PubMed]
24. Mavros MN, Athanasiou S, Alexiou VG, et al. Risk factors for mesh-related infections after hernia repair surgery: a meta-analysis of cohort studies. World J Surg 2011;35:2389-98. [Crossref] [PubMed]
25. Moreno-Egea A, Baena EG, Calle MC, et al. Controversies in the Current Management of Lumbar Hernia. Arch Surg 2007;142:82-8. [Crossref] [PubMed]
26. Sajid MS, Bokhari SA, Mallick AS, et al. Laparoscopic versus open repair of incisional/ventral hernia: a meta-analysis. Am J Surg 2009;197:64-72. [Crossref] [PubMed]
27. Sauerland S, Walgenbach M, Habermalz B, et al. Laparoscopic versus open surgical techniques for ventral or incisional hernia repair. Cochrane Database Syst Rev 2011;16:CD007781 [PubMed]
28. Pierce RA, Spitler JA, Frisella MM, et al. Pooled data analysis of laparoscopic vs. open ventral hernia repair: 14 years of patient data accrual. Surg Endosc 2007;21:378-86. [Crossref] [PubMed]
29. Novitsky YW, Cobb WS, Kercher KW, et al. Laparoscopic ventral hernia repair in obese patients: a new standard of care. Arch Surg 2006;141:57-61. [Crossref] [PubMed]
30. Marx L, Raharimanantsoa M, Mandala S, et al. Laparoscopic treatment of incisional and primary ventral hernia in morbidly obese patients with a BMI over 35. Surg Endosc 2014;28:3310-4. [Crossref] [PubMed]
31. Raftopoulos I, Courcoulas AP. Outcome of laparoscopic ventral hernia repair in morbidly obese patients with a body mass index exceeding 35 kg/m2. Surg Endosc 2007;21:2293-7. [Crossref] [PubMed]
32. Bower CE, Reade C, Kirby L, et al. Complications of laparoscopic incisional-ventral hernia repair: the experience of a single institution. Surg Endosc 2004;18:672-5. [Crossref] [PubMed]
33. Lee J, Mabardy A, Kermani R, et al. Laparoscopic vs open ventral hernia repair in the era of obesity. JAMA Surg 2013;148:723-6. [Crossref] [PubMed]
34. Krpata DM, Blatnik JA, Novitsky YW, et al. Evaluation of high-risk, comorbid patients undergoing open ventral hernia repair with synthetic mesh. Surgery 2013;153:120-5. [Crossref] [PubMed]
35. Moore M, Bax T, MacFarlane M, et al. Outcomes of the fascial component separation technique with synthetic mesh reinforcement for repair of complex ventral incisional hernias in the morbidly obese. Am J Surg 2008;195:575-9. [Crossref] [PubMed]
36. Halm JA, Heisterkamp J, Veen HF, et al. Long-term follow-up umbilical hernia repair: are there risk factors for recurrence after simple and mesh repair. Hernia 2005;9:334-7. [Crossref] [PubMed]
37. Okusanya OT, Scott MF, Low DW, et al. The partial underlay preperitoneal with panniculectomy for incisional abdominal hernia in the morbidly obese. Surg Obes Relat Dis 2014;10:495-501. [Crossref] [PubMed]
38. Warren JA, Epps M, Debrux C, et al. Surgical site occurrences of simultaneous panniculectomy and incisional hernia repair. Am Surg 2015;81:764-9. [PubMed]
39. Moreno-Egea A, Campillo-Soto A, Morales-Cuenca G. Does abdominoplasty add morbidity to incisional hernia repair? A randomized controlled trial. Surg Innov 2016;23:474-80. [Crossref] [PubMed]
40. Eid GM, Wikiel KJ, Entabi F. Ventral hernias in morbidly obese patients: a suggested algorithm for operative repair. Obes Surg 2013;23:703-9. [Crossref] [PubMed]
41. Eid GM, Mattar SG, Hamad G. Repair of ventral hernias in morbidly obese patients undergoing laparoscopic gastric bypass should not be deferred. Surg Endosc 2004;18:207-10. [Crossref] [PubMed]
42. Datta T, Eid G, Nahmias N. Management of ventral hernias during laparoscopic gastric bypass. Surg Obes Relat Dis 2008;4:754-7. [Crossref] [PubMed]
43. Schuster R, Curet MJ, Alami RS, et al. Concurrent gastric bypass and repair of anterior abdominal wall hernias. Obes Surg 2006;16:1205-8. [Crossref] [PubMed]
44. Chan DL, Talbot ML. Synchronous ventral hernia repair in bariatric patients. Obes Surg 2014;24:944. [Crossref] [PubMed]
45. Praveen Raj P, Senthilnathan P, Kumaravel R, et al. Concomitant laparoscopic ventral hernia mesh repair and bariatric surgery: A retrospective study from a tertiary care center. Obes Surg 2012;22:685-9. [Crossref] [PubMed]
46. Raziel A, Sakran N, Szold A. Concomitant bariatric and ventral/incisional hernia surgery in morbidly obese patients. Surg. Endosc 2014;28:1209-12. [Crossref] [PubMed]
47. Sharma G, Boules M, Punchai S, et al. Outcomes of concomitant ventral hernia repair performed during bariatric surgery. Surg Endosc 2017;31:1573-82. [Crossref] [PubMed]
48. Spaniolas K, Kasten KR, Mozer AB, et al. Synchronous ventral hernia repair in patients undergoing bariatric surgery. Obes Surg 2015;25:1864-8. [Crossref] [PubMed]
49. Hidalgo JE, Roy M, Ramirez A, et al. Laparoscopic sleeve gastrectomy: a first step for rapid weight loss in morbidly obese patients requiring a second non-bariatric procedure. Obes Surg 2012;22:555-9. [Crossref] [PubMed]
50. Newcomb WL, Polhill JL, Chen AY, et al. Staged hernia repair preceded by gastric bypass for the treatment of morbidly obese patients with complex ventral hernias. Hernia 2008;12:465-9. [Crossref] [PubMed]
51. Bittner R, Bingener-Casey J, Dietz U, et al. Guidelines for laparoscopic treatment of ventral and incisional abdominal wall hernias (International Endohernia Society [IEHS]): part 1. Surg Endosc 2014;28:2-29. [Crossref] [PubMed]
52. Silecchia G, Campanile FC, Sanchez L, et al. Laparoscopic ventral/incisional hernia repair: updated Consensus Development Conference based guidelines. Surg Endosc 2015;29:2463-84. [Crossref] [PubMed]
53. Menzo EL, Hinojosa M, Carbonell A, et al. American Society for Metabolic and Bariatric Surgery and American Hernia Society consensus guideline on bariatric surgery and hernia surgery. Surg Obes Relat Dis 2018;14:1221-32. [Crossref] [PubMed]