Controversies in Laparoscopic Ventral Hernia Repair

Abstract

Ventral hernia is one of the common anterior abdominal wall hernias after groin hernias. These hernias can be classified into primary hernias and secondary (incisional) hernias. Ventral hernia repair is a very common procedure performed in everyday surgical practice. Ventral/Incisional hernias are a frequent long-term complication of abdominal surgery. Roughly half of the incisional hernias develop within the first 2 years after abdominal surgery, and more than 70% manifest within 3 years. The recurrence rate of these hernias after primary suture repair exceeds 50%. However, after the prosthetic materials (meshes) were introduced in the repair procedure, this rate was reduced to 10–20%. The optimal approach with the best short- and long-term outcomes remains controversial. An increasing interest in laparoscopic surgery and its accessibility as well as the availability of innovative techniques have influenced the choice of repair. This chapter provides an overview of ventral hernias, their causes, risk factors, symptomatology, diagnosis, and different approaches to ventral hernia management, focusing mainly on laparoscopic surgery. Additionally, several controversies related to the technique will be discussed, such as mesh fixation, whether the hernia defect should be fixed or not, and mesh overlap. Pre- and post-operative care will also be covered.

1. Introduction

Ventral hernias are common conditions encountered by general surgeons, characterized by abdominal contents protruding through a weakness in the anterior abdominal wall. If left untreated, they can lead to discomfort, pain, and life-threatening complications. This chapter provides an overview of ventral hernias, covering their causes, diagnosis, and surgical management, as well as the latest advances in surgical techniques for repairing them.

Ventral hernias can manifest into two main categories: primary hernias, which include epigastric, umbilical, paraumbilical, and Spigelian hernias, and secondary hernias resulting from prior surgical procedures (known as incisional hernias).

The European Registry for abdominal wall hernias (EuraHS) released a classification system in 2012 [1] that categorizes ventral hernias based on their size:

• Small-sized hernia: This category encompasses hernias with a defect size of less than 1 cm.

• Medium-sized hernia: Hernias falling into this group have defects ranging from 1 cm to 4 cm in size.

• Large-sized hernia: This classification pertains to hernias with defects larger than 4 cm in size.

2. Anatomy of the abdominal wall

A good understanding of the abdominal wall’s anatomy is crucial for effectively managing hernia repair.

Rectus abdominis muscles form the central core of the abdomen. They are flanked laterally by the Linea semilunaris and separated medially by the Linea alba. These muscles originate from the xyphoid and the costal margin at the upper end, and they connect to the pubic symphysis at the lower end.

The anterior and posterior rectus sheaths are created by the ongoing extension of the external and internal oblique muscles.

There are three abdominal muscles that make up the lateral bulk of the abdominal wall: the transversus abdominis, the internal oblique, and the external oblique.

Upon coming together at the lateral margin of the rectus abdominis muscle, they give rise to the linea semilunaris and rectus sheath.

Transversus abdominis muscle fibers are responsible for forming the posterior rectus sheath in the upper one-third of the abdomen, while in the lower two-thirds, these fibers terminate on the lateral side of the rectus muscle, and the posterior rectus sheath is exclusively constituted by the transversalis fascia (Figures 1 and 2).

Figure 1.

Anatomy of the anterior Abdominal Wall. Axial view of the Abdominal Wall above the arcuate line.

Figure 2.

Anatomy of the anterior Abdominal Wall. Axial view of the Abdominal Wall below the arcuate line.

The fibers of the internal oblique muscle possess an oblique orientation and culminate at the linea semilunaris. Within the upper part of the abdomen, the anterior and posterior rectus sheath is formed by the anterior and posterior layers of the internal oblique muscle, while in the lower third of the abdomen below the arcuate line, the transversalis fascial layer the exclusive component of the posterior rectus sheath, as the posterior component of the internal oblique shifts anterior to the rectus abdominis muscle.

The external oblique muscle fibers are oriented at a right angle to the internal oblique fibers, and they assume a comparable anatomical arrangement in relation to the rectus sheath.

Based on the blood supply, the abdominal wall is divided into zones as follows.

Zone 1

• Located in the central upper abdomen.

• Blood supply from the descending superior epigastric artery, a derivative of the internal mammary artery in the upper direction, and the ascending inferior epigastric artery, arising from the external iliac artery in the lower direction, delivering blood to the periumbilical perforator vessels.

Zone 2

• Located below the arcuate line.

• Blood supply is derived from branches of the inferior epigastric artery medially, and superficial circumflex iliac artery laterally.

Zone 3

• Located lateral to the Linea semilunaris and above the arcuate line.

• Blood supply is derived from the musculophrenic artery superiorly, and the deep circumflex iliac artery inferiorly.

The abdominal wall nerves run between the transversus abdominis and internal oblique muscles. The top nerves arise from spinal roots T6-T12, while the L1 nerve root innervates the lower area via the ilioinguinal and iliohypogastric nerves.

3. Causes of ventral hernia

Several factors play a role in the formation of hernias. Hernias can be linked to various medical conditions, including connective tissue disorders, as well as collagen-related abnormalities.

The majority of hernias are associated with disorder of a collagen metabolism, where the type I to III collagen ratio plays a key role. A lower ratio, around 5 on average, increases the likelihood of hernia development [2].

Common risk factors include:

• Weakness in the abdominal wall: aging, or previous abdominal surgeries.

• Pregnancy can strain and weaken abdominal muscles, making women more susceptible.

• Obesity: Excess weight stresses abdominal muscles.

• Chronic cough: increases intra-abdominal pressure.

• Straining during bowel movements.

• Trauma or abdominal wall injury.

• Smoking: Impaired body healing and increased hernia risk are linked to smoking.

3.1 Symptoms

The symptoms of ventral hernias can differ, and some individuals may not exhibit any symptoms:

• A bulge or lump in the abdominal region, especially while standing or straining.

• Discomfort or pain in the affected area.

• In certain instances, the hernia may become incarcerated, resulting in the entrapment of abdominal contents. This situation can lead to intense pain, nausea, and vomiting, necessitating urgent medical attention.

3.2 Diagnosis

The identification of an abdominal lump during a physical examination typically validates the diagnosis. For obese patients, feeling the lump by palpation might be challenging, and using ultrasound (US) or computed tomography (CT) can be useful for confirming the diagnosis.

4. CT Imaging in ventral hernia

CT serves as a valuable tool for the preoperative assessment of most patients, providing information about the size and position of the hernia defect, its relation to nearby surrounding structures, involvement of the bowel, and loss of domain. It is a relatively lower cost compared to magnetic resonance imaging (MRI) [3].

This imaging technique is especially crucial for atypical ventral hernias situated away from the midline, such as parastomal and spigelian hernias.

Some studies have explored the use of ultrasound for diagnosing and monitoring incisional hernias, yielding positive outcomes. Ultrasound is an appealing imaging option due to its cost-effectiveness and reduced radiation exposure for patients who often undergo multiple irradiation procedures.

However, ultrasound has limitations such as being highly dependent on the user’s expertise, inability to accurately assess the size of larger hernias, and limited capabilities in evaluating other factors like mesh location, bowel patterns, and occult hernias [4].

Preoperative considerations:

• Patient selection:

• Indications:

  Symptomatic hernia, risk of incarceration: narrow-necked large hernias containing bowel on CT [5].

• Relative contraindications [5]

  Hernia size: large >10 CM OR small <3 cm,

  High BMI, multiple previous scars,

  Hernia in unusual locations [6]: e.g. subxiphoid [5], flank, suprapubic [7] in which high-grade experience is required to place and fix mesh subfascial and avoid injuring vital structures or posterolateral hernias where is difficult to anatomically obtain mesh landing zone,

  Strangulation/incarceration. These are considered as relative contraindications.

• Special circumstances [5, 8] in which it is difficult to obtain safe laparoscopic repair:

  1. Loss of domain.

  2. Presence of skin graft or abdominal wall flaps (e.g. TRAM flap).

  3. Presence of enterocutaneous fistula.

  4. Loss of abdominal wall muscles like in gunshots.

  5. Recurrent hernia that require large mesh removal are considered as absolute contraindications of laparoscopic ventral hernia repair.

• Medical comorbidities [5, 8]:

  Severe COPD, congestive Heart failure and child C Liver Cirrhosis are absolute contraindications of laparoscopic ventral hernia repair.

• Patient Optimization [8]:

  • Weight reduction

  • Stop smoking.

  • Treat constipation

Techniques [8, 9]:

• General anesthesia

  • Antibiotics during induction according to the local hospital policy.

• Supine position and abdominal prep +/− incise drape (e.g. Ioban)

• Ports positioning:

  • Commonly three ports are placed at the left side of the abdomen +/− assistant port at the right side of the abdomen

• Camera and mesh insertion port: 10–12 mm port at left upper quadrant midclavicular line below the tip of 11th rib mainly inserted in open Hasson technique fashion. Other options include Veress needle and optical port.

• Another 2 x 5 mm ports were inserted under vision in the anterior axillary line.

• Surgical field/space:

  • Intraabdominal (in IPOM), most commonly.

  • Preperitoneal space (in TAPP) [10]: peritoneum incised 7–8 cm distance from linea alba parallel to the midline and 12–15 cm long craniocaudally, preperitoneal space developed around the hernia and to the contralateral side prior to hernia reduction.

  • Retro rectus space (in eTEP) [6]: 15 mm subcostal incision, balloon space used to create retro rectus space to pubic bone medial to linea semilunaris to preserve neurovascular bundles, brief intraperitoneal entry to dissect and inspect the hernia contents, retro rectus space creation continued to the contralateral side.

  • Oblique muscle complex (in endoscopic component separation) [11]: create space between external and internal oblique, perforator sparing technique used to release external oblique from its origin obliquely, mainly used as adjunct for open ventral/incisional hernia repair but can also be used for laparoscopic repair.

• Adhesiolysis and hernia reduction: Care not to injure the bowel and also meticulous hemostasis (consideration of open conversion largely depend on the operative experience but generally significant bowel injury or bleeding that is difficult to control laparoscopically should be an indication of early conversion).

• Hernia defect measurement and closure: Hernia defect can be measured laparoscopically using tape or externally sometimes with the aid of a spinal needle passed close to the edge of the fascial defect. Hernia defect is then closed either laparoscopically or transfacially using a fascial closure instrument or endo close.

• Mesh placement and fixation:

  • Allowing 4–5 cm overlap around the hernia defect.

  • Fixation: tacks +/− anchoring sutures. Tacks can be absorbable or non-absorbable. The general consensus is to use absorbable tacks although there is no strong evidence to support it [12]

• Location of the mesh:

  • Intraperitoneal Onlay Mesh (IPOM): It is the commonest mesh placement technique. Easier but higher mesh complications rate. Other techniques: reduce mesh complications rate but technically difficult).

  • Transabdominal preperitoneal (TAPP) [10]: It is suitable for medium-sized hernia (2–4 cm according to European Hernia Society [13].

  • Extended totally extra peritoneal (eTEP) [6] which can be done as Rives Stoppa.

  • Preperitoneal mesh placement procedure or accompanied with posterior component separation (i.e. Transversus abdominis release).

Types of mesh:

Three main types of Mesh:

1. Composite

   • Polypropylene collagen (Parietene, Sofradim, Trevoux, France).

   • Polypropylene polytetrafluoroethylene (Composix, CR Bard, Cranston, NJ, USA)

   • Monofilament polyester collagen (Sympotex, Medtronic, UK)

2. Expanded polytetrafluoroethylene (Dual mesh, Gore-Tex, Gore Medical, Flagstaff, AZ, USA)

3. Polypropylene covered with oxidized regenerated cellulose (Proceed (Ethicon).

Complications [5, 8]:

1. Bowel injury (enterotomy) 2–6%: Intra op management depend on the degree of injury or contamination. Option will be:

   • Repair the injury (lap or open) + repair the hernia with or without mesh.

   • Repair the injury (lap or Open) + delayed hernia repair either less than 1 week or after 6–8 weeks.

   • Delayed enterotomy usually as result of delayed diathermy injury or tacks injury and should be managed by laparotomy, repair /excise or divert the injury + mesh removal.

2. Seroma formation: more than 90% of patients develop seroma which is likely to spontaneously resolve. Therefore treatment is reserved to symptomatic seroma (1–24%) or persistent seroma for more than 8 weeks (3–4%) which can be managed with sterile aspiration or drainage, rarely chronic seromas might require mesh removal.

3. Post-Operative Ileus (1–3%): usually managed expectantly, reduced bowel manipulation may reduce the incidence of post-op adynamic ileus.

4. Infections:

   • Surgical site infections: 2.8% can be treated with dressing and antibiotics.

   • Skin Cellulitis: 2–4% could be as a result of an inflammatory reaction caused by the mesh or infected mesh, treated with antibiotics. Low evidence of prophylactic antibiotic use.

   • Mesh Infection: 0.6% difficult to treat and may require mesh excision, the following strategies can be adopted:

     • Antimicrobial therapy + image-guided drainage of abscesses.

     • Mesh salvage, debridement + vac therapy with antimicrobial therapy, especially of mesh is well incorporated.

     • Mesh removal, for septic patients or when the above measures failed.

   • Fistula formation [14]:0.1% usually as a result of chronic mesh erosion, unrecognized enterotomy or anchoring suture injury. Treated with mesh removal and surgical repair.

5. Chronic pain more than 6 weeks post-operative, 1.3–3.3%, usually as the result of tacks or anchoring stitch, rarely as a result of neuroma development. It can be managed with, NSAID, nerve blocks, local anesthetic or steroid injections. Surgical removal of anchoring stitches or tacks.

Post-operative care [8]:

• Adequate analgesia: range from simple analgesia to PCA.

• DVT prophylaxis should be initiated within 24 hours.

• Patient education: lifestyle adjustments to reduce hernia recurrence, recognize signs of infection or hernia recurrence

5. In summary

The abdominal wall’s anatomy is crucial for effective hernia repair.

Blood supply zones in the abdominal wall are defined based on location and vascular sources.

Diagnosis involves physical examination, ultrasound, or computed tomography (CT) imaging.

CT imaging is cost-effective and useful for assessing hernia size, location, and relation to nearby structures. Ultrasound is another option but has limitations. Understanding ventral hernias and their diagnosis is essential for effective management and surgical repair.

Preop considerations for hernia surgery include patient selection, indications, hernia size, high BMI, previous scars, and hernia in unusual locations. Special circumstances include loss of domain, skin graft or abdominal wall flaps, enterocutaneous fistula, loss of abdominal wall muscles, and recurrent hernias requiring large mesh removal. Patient optimization includes weight reduction, stopping smoking, and treating constipation.

Operatively Surgical fields include intraabdominal (IPOM), preperitoneal space (TAPP), retro rectus space (eTEP), and oblique muscle complex (endoscopic component separation). Hernia defect measurement and closure are done laparoscopically or externally, and the hernia defect is closed either laparoscopically or transfacially.

Mesh placement and fixation are performed using intraperitoneal Onlay Mesh (IPOM), transabdominal preperitoneal (TAPP) and extended totally extraperitoneal (eTEP). Mesh types include polypropylene + collagen, polypropylene+polytetrafluoroethylene, monofilament. Polyester+collagen, expanded polytetrafluoroethylene, and polypropylene covered with oxidized regenerated cellulose.

Complications include bowel injury (enterotomy). The option 0f treatment depends on the degree of injury or contamination.

In conclusion, laparoscopic ventral hernia repair is a challenging process that requires careful patient selection and optimisation together with the availability of surgical experience. Therefore, complex laparoscopic ventral/incisional hernia repair should be reserved to centers where high volume of these surgeries are conducted in regular bases.