Retrorectus sublay mesh repair using polypropylene mesh: Cost-effective approach for laparoscopic treatment of ventral abdominal wall hernias.

INTRODUCTION: Laparoscopic repair of ventral abdominal hernias has become a standard of care. The surgery involves placement of a composite mesh with 3-5 cm overlap at the edges of the defect. The disadvantage of this repair is one, the composite mesh used for intraperitoneal placement is quite costly and two, it leaves a foreign body inside the peritoneal cavity, with the potential to cause problems in the future. To circumvent both these issues, we have developed a new approach, called the retrorectus sublay Mesh (RRSM) repair, which allows placement of a plain polypropylene mesh in an extraperitoneal plane. PATIENTS AND METHODS: Patients with paraumbilical hernia and lower midline incisional hernias were included in this pilot study performed at a single centre by the same surgeon. The steps of the technique are described in detail.
RESULTS: Since 2016, a total of 52 patients were operated by this technique, including both male and female patients. It included patients with para-umbilical hernias as well as incisional hernias. The RRSM repair could be successfully carried out in all the patients. In six of the patients, transversus abdominis release was added as the defect size was large to allow closure of the defect. The results were satisfactory with a low morbidity and no mortality.
CONCLUSION: In our opinion, the RRSM technique is an important tool in the armamentarium of the laparoscopic surgeon dealing with ventral abdominal hernias, allowing placement of polypropylene mesh in an extraperitoneal space. It allows significant cost savings as compared to the prevalent intraperitoneal onlay mesh repair.

INTRODUCTION

Up to one-fifth of patients undergoing major abdominal surgeries develop incisional hernias.[123] Laparoscopic repair of ventral hernia was first introduced by LeBlanc and Booth in 1993.[4] With its acknowledged advantages in the form of lower wound infection rates and shorter hospital stay, laparoscopic repair is now considered as a standard form of the management of ventral abdominal wall hernias which are not associated with significant domain loss.[5] Conventional laparoscopic repair of hernia consists of bridging the defect from the peritoneal side with a mesh of size adequate to ensure at least 3–5 cm overlap of the edges of the defect, termed the intraperitoneal onlay mesh (IPOM) repair. Recently, a newer concept of IPOM repair is practiced in which the fascial edges of the defect are sutured in apposition before reinforcement with mesh, named the IPOM-Plus repair.[6] In both the IPOM and IPOM-Plus repairs, the mesh that is used for reinforcement is a composite mesh, which differs from the routine polypropylene or polyester meshes in that the peritoneal cavity contents are separated from the polypropylene or polyester framework of the mesh by another resorbable or biodegradable material that either forms a barrier between the peritoneal cavity and the framework of the mesh or is coated over each of the strand of the framework of the mesh. This resorbable or biodegradable material layer retards the formation of adhesions between the framework of the mesh and the peritoneal contents.

However, such composite meshes are quite costly, retailing at almost 10 times their plain polypropylene mesh counterparts, size for size. In addition, the majority of surgeons use absorbable tacks to fix the mesh to the abdominal wall in addition to the corner or axial transfixation sutures, which again adds to the cost. Uncoated polypropylene meshes are not advocated for intraperitoneal placement due to the risk of bowel adhesion and fistulisation.[7] To reduce the cost of surgery, we have developed a technique of laparoscopic hernia repair using polypropylene mesh for reinforcement, yet without allowing the mesh to be exposed to the contents of the peritoneal cavity. We describe our preliminary experience in this study.

PATIENTS AND METHODS

The surgical technique was developed and initially adopted in adult patients with para-umbilical hernias. Gradually, it was also applied to patients with lower midline infra-umbilical hernias, where the defect size was <5 cm. Thereafter, it has been adopted in patients with lower abdominal midline incisional hernias, where the defect size is between 5 and 8 cm. In such cases, laparoscopic transversus abdominis release (TAR) is also added as a step to the surgery.

The major steps of the operation are described. The patient is placed supine on the table with nasogastric tube and urinary catheter in situ. Pneumoperitoneum is achieved with Veress needle inserted through Palmar's point. The initial pressure is set at 12 mm Hg. The ports are then inserted in the positions depicted in Figure 1. We use a 5 mm 30° laparoscope, and the 10 mm epigastric port [A, in Figure 1] is to facilitate insertion of the mesh. Placing the laparoscope in the epigastric port and using the right and left midclavicular line ports [B and D, in Figure 1] as working ports, adhesiolysis is carried out, if required and the hernia contents are reduced. Then, placing the laparoscope in the right midclavicular port [B, in Figure 1], and using the epigastric and right flank ports [A and C, in Figure 1] as working ports, the falciparum ligament and the ligamentum teres are divided at about 7–8 cm cranial to the upper edge of the fascial defect of the hernia. The distance is marked by measuring with a tape and then inserting a spinal needle through the abdominal wall at the chosen point. The next step consists of placing the transverse incision over the peritoneum and posterior rectus sheath, across the breadth of both the recti muscles, 7–8 cm above the upper edge of the fascial defect using monopolar cautery hook. The falciparum ligament cranial to the point of division is taken down as it may obstruct the view for the laparoscope.

Figure 1

Port positions. (A-D) Denote the ports. The dotted outlines X and Y denote possible hernia sites for which these port positions are optimal

Thereafter, the laparoscope is shifted to port A and using ports B and D as working ports, the plane is developed between the recti muscles ventrally and the posterior rectus sheath along with peritoneum dorsally. For this, the left hand of the surgeon holds the posterior edge of the rectus sheath with a locking grasper, and the right-hand uses a monopolar hook cautery to divide the fascial adhesions between the posterior aspect of the belly of the rectus muscle and the posterior rectus sheath. The retrorectus compartments are separated in the midline by the linea alba. Here, the posterior sheath is divided about 2–3 mm away from the midline, taking care not to breach the layer of pre-peritoneal fat and peritoneum dorsally, on both the sides, to create a single retrorectus compartment.

At the site of the hernia, the defect in posterior fascia will be encountered. The peritoneal sac entering the hernia defect is opened up and the lower edge of the defect identified. The same plane is developed caudal to the defect on either side. Dissection is carried out 7–8 cm caudal to the lower margin of the defect. In cases of lower midline incisional hernias, the dissection will proceed up to the pubic symphysis. The space created caudally in such a situation is identical to the midline dissection required in totally extraperitoneal (TEP) repair of groin hernias, and the surgeon will be working in familiar territory.

Care should be taken not to damage the laterally placed neurovascular bundles as they enter bellies of the recti muscles to avoid denervation myopathy. In addition, attention should be paid to protecting the superior epigastric vessels cranially and the inferior epigastric vessels caudally.

If TAR is to be added, then the posterior rectus sheath is divided about 2–3 mm from the lateral edge, medial to the neurovascular bundles, using monopolar hook cautery. At the first division, the peritoneum and pre-peritoneal fat fall dorsally as the layers are separated by the carbon dioxide insufflation. The incision is extended craniocaudally as required, and the space is easily created by the combination of blunt and sharp dissection as it is a relatively avascular plane. Laterally, the space can be dissected out to the level of the anterior axillary line.

Mirror image dissection is done bilaterally.

The fascial defect is sutured using 1-0 polydioxanone barbed suture (V-LOC, Covidien, Medtronic Inc., USA) after reducing the pneumoperitoneum pressure to 6 or 8 mm Hg. Measurements of the space created are taken using a length of black silk and a self-fixating mesh (Pro-Grip, Covidien, Medtronic, USA) of adequate size, with a minimum of 5 cm overlap of the edges of the fascial defect is placed [Figure 2]. Three transfascial sutures are placed in the mesh in the midline to ensure correct orientation, and after spreading it out, it remains in position and does not require any additional fixation. The surgeon should ensure that the rough surface remains towards the recti muscles and the smooth surface is facing towards the posterior rectus sheath.

Figure 2

Mesh placed between the recti muscles (A) and the posterior rectus sheath (B)

The transverse incision at the upper end of the posterior rectus sheath is closed using 1-0 polydioxanone barbed suture (V-LOC, Covidien, Medtronic Inc., USA), shifting the laparoscope to port B and using ports A and C, for this step. If the surgeon is uncomfortable with suturing in this position, the flap can also be secured using absorbable tackers.

After closing the fascia of the 10 mm port, controlled deflation is carried out.

Nasogastric tube is removed before extubation. The patient is started liquids orally after 4 h, and then solids are added as tolerated. The patient is mobilised after 4 h and discharged as soon as he or she is able to tolerate oral diet.

RESULTS

We adopted this innovation in our practice since November 2016. Initially, we were performing it only for adult patients with para-umbilical hernias. Later on, we offered it to patients with lower abdominal vertical midline incisional hernias with maximum transverse defect size up to 5 cm width. Encouraged by the results, we have now started to perform the repair after addition of TAR in adult patients with lower abdominal vertical midline incisional hernias with maximum transverse defect size up to 8 cm. Patients with defect size >8 cm are offered an open repair with anterior or posterior component separation and are not included in this study.

The demographics of the patients are summed up in Table 1.

Table 1

Patient demographics

Variable	Value (N)
Total number of patients	52
Male: female	22:30
BMI (range)	24.5 kg/m2 (23-39 kg/m2)
Diabetes mellitus (%)	9 (17.3)
Smoking (%)	4 (7.8)

BMI: Body mass index

According to the procedure performed, the patients were divided into three groups. Out of the 52 patients in the study, 32 patients in Group A had paraumbilical hernia and were subjected to laparoscopic retrorectus sublay mesh (RRSM) repair. Theremaining patients had lower abdominal incisional hernias, of which 14 (Group B) underwent laparoscopic RRSM repair while in six patients (Group C), a laparoscopic TAR procedure was added through the same approach after RRSM repair. Two patients had recurrent hernias, both after open mesh repair, one a para-umbilical hernia and one an incisional hernia. These are summarised in Table 2.

Table 2

Patient distribution according to indication and procedure performed

Number of patients (n)	Indication	Procedure performed
32	Para-umbilical hernia	RRSM
14	Incisional hernia	RRSM
6	Incisional hernia	RRSM+TAR

RRSM: Retrorectus sublay repair, TAR: Transversus abdominis release

The operative findings are summarised in Table 3.

Table 3

Operative and post-operative outcomes

	Group A	Group B	Group C
Average operating time in min (range)	108 (94-145)	121 (106-165)	145 (125-185)
Median length of stay (days)	2	2	3
Median length of drain (days)	-	-	3
Conversion to open	Nil	Nil	Nil

After discharge, the patients were called for follow-up at 10 days, 1 month and 3 months thereafter. Patients were reminded about their follow-up appointments by cellular phone calls and social media apps like WhatsApp, ensuring that all the operated patients were kept track of. The follow-up of the patients ranged from 15 days to 20 months.

In the post-operative period, one patient developed a bulge at the site of the original incisional hernia on straining, through which the mest could be palpable. However, intra-peritoneal contents were not herniating through the defect. Ultrasonography confirmed divarication of recti. Two of our patient developed clinically noticeable seroma within 15 days of surgery. They were asymptomatic and managed conservatively. None of the patients developed mesh infection or recurrence.

DISCUSSION

In 1981, Kaufman et al. reported a case of enterocutaneous fistula arising from the intraperitoneal placement of a polypropylene mesh.[8] Similar results were reported by other surgeons.[910] Thereafter intraperitoneal placement of polypropylene meshes was discouraged, with the recommendation that direct contact between mesh and bowel should be avoided.[11] With the advent of laparoscopic repair of ventral wall hernia, this trend continued and led to the popularity of coated or composite mesh in which the polyester or polypropylene is separated from the peritoneal contents by a coating or a layer of resorbable biodegradable material, which varies depending on the manufacturer. A feature common to these newer meshes is that they are several times costlier than their plain polypropylene counterparts, size for size. The technique of RRSM, developed at our centre, provides the solution in the form of placement of polypropylene mesh in a pocket between the recti muscles ventrally and the posterior recti sheaths and peritoneum dorsally.

The traditional IPOM or IPOM-plus surgery requires fixation of the mesh to the ventral abdominal wall which is either carried out by placing transfascial sutures at the corners or in the midline of the mesh and using either absorbable tackers or intra-corporeal sutures in between.[12] The use of absorbable tackers adds significantly to the cost of the surgery. With the RRSM technique, the mesh is placed in a potential space created by surgical dissection, which would collapse with release of pneumoperitoneum. Moreover, any rise in intra-abdominal pressure would further firmly sandwich the mesh between the posterior rectus sheath and peritoneum on one side against the recti muscles on the other side. Thus, we opt to place only midline transfascial fixation sutures in the mesh. There is no necessity for intracorporeal suturing of the mesh or fixation with tackers, greatly increasing the simplicity of the surgery and reducing the cost at the same time. There is concern that the use of multiple transfascial sutures can lead to increased post-operative pain, perhaps due to entrapment neuropathy or muscular ischemia.[13] Conversely, other authors report a decrease in post-operative pain after switching from tacker fixation to suture fixation.[14] The use of self-fixating mesh has abolished the need for transfascial sutures or tackers, thus possibly providing the benefit of lower chronic abdominal pain. That is also the reason why we prefer the self-fixating mesh as compared to the plain polypropylene mesh as the marginal increased cost of the former is offset by the absence of lateral fixation required, either by sutures or tackers and the subsequent time saved that is characteristic of the latter.

The cost savings as compared to the more prevalent IPOM repair are significant. In India, the cost of a composite mesh (used in IPOM repair of 15 cm × 15 cm size is approximately INR 28,000/-and a tacker costs an additional INR 22,000/-. In contrast to this, the self-fixating polypropylene mesh that we use in the RRSM approach costs just INR 6500/-.

The creation of the space required for placing the mesh adds to the time of surgery. Though our operative times for the RRSM approach are higher than for IPOM approach,[15] they are not inordinately so. Vacuum drain was placed in patients of Group C, due to the extensive mobilisation done after TAR. In the six such patients included in this series, the drainage was serosanguineous in nature, and the drain tube could be removed after 3 days in five patients and after 5 days in one patient, requiring prolongation of their stay beyond the norm of 2 days. All the surgeries were comfortably completed laparoscopically.

In about 7% of our patients, seroma was detected on clinical examination and confirmed with ultrasonography. The reported incidence of seroma after laparoscopic ventral abdominal wall hernia repairs varies from 0.5% to 78%,[1617] depending on the protocol followed for its detection.[18] All patients were reassured and asked to wait with complete resolution of seromas within 3 months of their first detection.

Mesh bulging or ‘pseudo-recurrence’ is a known phenomenon reported after laparoscopic ventral hernia defect in with the aponeurotic edges diverging on straining manifesting as bulging out of the mesh and is a significant factor in patients’ dissatisfaction with outcomes.[19] Whether suturing the fascial defect (IPOM-Plus) or not (IPOM) affects the incidence of this event is controversial.[202122] We always suture the defects in the dorsal layer consisting of posterior rectus sheath plus peritoneum as well as the ventral layer.

Sosin et al. reviewed the adverse reactions and outcomes according to the plane of mesh placement.[23] For laparoscopic surgery, as compared to the mesh place in the interposition (bridging the defect as in IPOM) or underlay (dorsal to the defect as in IPOM Plus), the placement of the mesh in the retrorectus space provides better results and outcomes for overall complications, infection, hematoma/seroma, recurrence and mesh removal. However, the advantage reached statistical significance only for the parameters of hematoma/seroma formation and recurrence.

Other surgeons have also attempted to dissect and place the mesh in an extraperitoneal location. An approach similar to Trans Abdominal Pre-Peritoneal repair for inguinal hernia was described.[24] However, the peritoneal layer is very flimsy and firmly attached to the posterior aspect of the rectus sheath cranial to the arcuate line. Moreover, it is technically difficult to carry out this dissection from the lateral flank approach.[25]

Similarly, Belyansky has described a direct approach to the retrorectus space called the ‘eTEP’ approach by assessing this plane through a small skin incision and subsequently using a balloon to create the space.[26] The trocars are placed within the lateral limits of the recti muscles. While they have commented on the utility of this technique, we feel that the proximity of the trocars to the hernia site would be a hindrance. Moreover, should the midline peritoneum be breached during the division of the medial borders of the posterior recti sheaths to establish continuity across both spaces, suturing this defect may not be ergonomically easy. Third, the requirement of bilateral TAR would need the placement of two more trocars on the opposite side.

Reinpold has described an approach of directly placing an incision over the hernia, dissecting the sac and then entering the retrorectus space, calling it the Mini or Less Open Sublay operation.[27] However, it requires the need of a specialised light source with central channel for the instrument developed specifically for this surgery, known as Endtorch™. Besides, since the incision required varies from 2 to 12 cm, depending on the size of the hernia, it should be considered more as a variation of the open sublay repair rather than that of the laparoscopic repair.

There are several drawbacks to our study. First, it is a non-randomised selective study to check the feasibility of the new technique. Second, the number of patients are less. Moreover, the follow-up of a maximum of 14 months is inadequate to accurately report long-term complications like recurrence.

However, we feel that this is an exciting new approach which allows the use of the polypropylene mesh in an extra-peritoneal compartment. This leaves the peritoneal surface almost virginal. A recent study has shown that even the placement of a composite or barrier mesh intraperitoneally increases the morbidity and adverse events in subsequent laparotomies.[28] Perhaps, the greatest advantage of the RRSM technique, apart from its cost-saving, would be minimal disturbance of the parietal peritoneal surface of the abdominal cavity.

We feel that a larger study with more centres involved would go a long way in establishing the feasibility and easy reproducibility of this technique.

CONCLUSION

The RRSM technique is safe and feasible allowing significant cost-saving by using self-fixating polypropylene mesh instead of composite mesh. Since minimal mesh fixation is required as the mesh is held between the two layers of ventral abdominal wall under Laplace's law, one can even save on the cost of tackers required for mesh fixation in conventional laparoscopic repair of ventral hernia. A larger study, with the recruitment of sufficient patients to reach statistical significance will go a long way in establishing this technique in the armamentarium of surgeons dealing with abdominal wall hernias.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.