Ventral ETEP Versus REPA,Comparison of Two Novel Minimally Invasive Techniques for Midline Defects

Introduction

Diastasis of the rectus muscles of the anterior abdominal wall is defined as the separation of the linea alba or midline due to the laxity of the intertwined fibers that make up the aponeurosis of both muscles. There are numerous classifications, but in consensus, a distance greater than 2 cm is defined as pathological. ¹ It can be of a congenital or acquired nature favored by factors such as obesity, COPD, pregnancy, and previous surgeries.^2,3 Symptoms might vary from esthetic discomfort to functional problems of the abdominal wall, including alterations in the pelvic floor functions (gynecological, urological, and intestinal) and chronic low-back pain. In addition, it is usually associated with other defects of the anterior abdominal wall such as umbilical or epigastric hernias. ⁴

When diastasis of the rectus muscles is associated with other midline defects, it is highly recommended to correct both in the same surgical procedure. Hernia repair on an anatomically weakened linea alba increases the chances of recurrence.^1,5,6

The minimally invasive repair of hernias and midline defects is in full growth. Endoscopic correction of these defects is proposed in patients who do not have associated lipodystrophy or large dermal-fatty flaps in whom it would be prudent to perform abdominoplasties to achieve a better esthetic result.

Two endoscopic techniques are to be considered due to their growing popularity: the preaponeurotic repair (REPA)^6–8 and the extended vision extraperitoneal (ETEP) approach.^9,10 During REPA, a preaponeurotic dissection is performed with the closure of the linea alba and the associated defects with an onlay mesh placement. ETEP creates a retromuscular space following the Rives principles where a big mesh is placed after the midline closure.

This report aimed to compare both techniques in terms of surgical procedure, outcomes, and patient evolution.

Methods

This was a retrospective study performed at a tertiary care academic center between 2017 and 2022. All consecutive patients operated on for midline hernias and rectus diastasis using REPA and ETEP were included. Patients with a hernia defect greater than 5 cm, loss of domain, large dermatomal flaps, active skin infections, complicated acute hernias, or patients with contraindications for general anesthesia were excluded.

Both techniques were offered to the patient in the preoperative consultation. The only cause for indicating the ETEP technique without the possibility for REPA was the presence of a concomitant inguinal hernia. There were no other selection criteria, and patients could choose between one or the other according to their preferences and objectives.

The size and characteristics of the defects to be treated were assessed preoperatively with a physical examination, ultrasound of the abdominal wall, and abdominal CT scan.

All patients underwent general anesthesia, and preoperative antibiotic prophylaxis was given with cefazolin 2 g or clindamycin 300 mg single dose in those allergic to penicillin. All patients underwent prosthetic reinforcement with a macroporous polypropylene mesh.

The surgical techniques were performed as follows:

REPA

The patient was settled in a supine position with open legs. A suprapubic 1 cm incision was performed, and a preaponeurotic dissection was started using scissors. Once enough space was created, a 10 mm optical trocar was placed. Two 5 mm trocars were placed at each side. Monopolar energy was used to dissect the supra-aponeurotic space. The umbilicus was always sectioned from the aponeurosis. The midline and its associated defects were closed using a continuous barbed suture. An onlay mesh was placed and fixed with prolene 2-0 sutures covering the midline and the defect completely. Vicryl suture was used to fix the umbilicus back to its position. Drains were used routinely (Fig. 1) https://1drv.ms/v/s!AgN0ip79ePemgYsAARpoumKAEHwQ-g?e=zVdSmf (Video 1).

OPEN IN VIEWER

FIG. 1.

(a) Trocar placement. (b) Subcutaneous dissection. (c) Hernia reduction. (d) Defect closure. (e) Mesh placement.

ETEP

The patient was placed in the supine position with open legs. The anterior sheet of the rectus muscle was opened, and a retromuscular space was created. A 10 mm trocar was then positioned, and the camera was used along the pneumoperitoneum to complete the blunt dissection. Another 10 mm and two 5 mm trocars were placed. The space was first created under the umbilicus, and monopolar energy was used to complete the dissection upwards. The crossover was made in a caudal to cephalic way to achieve the left retromuscular space. The hernia defect was recognized and reduced. A 2-0 PDS barbed suture was used to close the posterior wall. A 0 barbed suture was used for the closure of the anterior midline. A big propylene mesh was used to cover the whole dissected space. Drains were used routinely (Fig. 2) https://1drv.ms/v/s!AgN0ip79ePemgYsBQfnpKC57s9GYRw?e=izvWEm (Video 2).

OPEN IN VIEWER

FIG. 2.

(a) Trocar placement. (b) Retromuscular dissection. (c) Crossover. (d) Hernia reduction. (e) Anterior midline closure. (f) Posterior midline closure. (g) Mesh placement.

In both procedures, drains were extracted when the output was under 30 cc per day. An abdominal girdle was indicated for 30 days.

Follow-up visits were at 15 days and 30 days and 6 months postoperative. Diagnostic images were only required if a complication or recurrence was suspected. All clinically detected seromas were routinely punctured and aspirated with an aseptic technique.

Age, sex, BMI, ASA (American Surgical Anesthesiologic Classification), surgical time, need for conversion to open surgery, time of stay, seroma, hematoma, surgical site infection (SSI), recurrence, and re-interventions were assessed. Seroma was defined as a serous liquid collection in the dissected space. The management of the seromas was also analyzed for each case. SSI was defined by the presence of cellulitis, fever, or pathological secretion through drains or wounds.

Results

For the present study, 148 patients were included. From them, 62 patients received the REPA procedure, and 86 were operated on using the ETEP technique (Fig. 1). Gender distribution was similar for both groups with 58% (n = 36) males in the REPA group and 51.2% (n = 44) males in the ETEP group (p = 0.4). Within women, postpartum pathogenesis was responsible for 77% (n = 20) in the REPA group and 83% (n = 35) in the ETEP group (p = 0.4). The average age was 50 years (±14.7) for REPA and 51.8 years for ETEP (±11.47) (p = 0.45). The mean BMI was 28.6 (±4.5) for REPA and 29.1 (±5.3) for ETEP (p = 0.52). Most of the patients were classified as ASA II: 74.2% and 82.6% in REPA and ETEP, respectively (p = 0.28) (Table 1).

Defects were classified following the EHS criteria (Table 2). ¹¹ In the REPA group, 77.2% (n = 48) were primary (11 small, 35 medium, and 2 large), and 22.58% (n = 14) were incisional hernias: M3 = 9 and M2 = 5; 5 small, 9 medium. In the ETEP group, 82.56% (n = 71) were primary defects (14 small, 54 medium, and 3 large) and 17.44% (n = 15) were incisional hernias: 3 M2, 11 M3, 1 M4; 4 small, 9 medium, 2 large. No statistical differences were found (p = 0.43).

Diastasis of the rectus muscles was associated with 61 patients in the REPA group and 65 in the ETEP group. The average rectus abdominis diastasis size was 2.7 cm (range of 2.2–5 cm) and 2.9 cm (2.2–7 cm) for the REPA and ETEP group, respectively. A transversus abdominis release (TAR) procedure was performed in one case in the ETEP group. In 16 cases of the ETEP group, inguinal hernia repair was associated.

For every procedure, a macroporous polypropylene mesh was used. In the REPA group mean size of the mesh used was 14.83 cm (±2.4) by 10.59 cm (±2.5). In the ETEP group, the mean mesh size was 25.3 cm (±3.1) by 15 cm (±1.2) (p = 0.04).

Ambulatory procedures could be performed in 32.3% (n = 20) REPA and 20.9% (n = 18) ETEP without statistical differences (p = 0.23). Regarding days of stay, in the REPA group, 64.5% (n = 40) of the patients were admitted for 1 day and 3.2% (n = 2) for two or more days; in the ETEP group, 72.1% (n = 62) stayed for 1 day and 7% (n = 6) for two or more days.

Surgical time was statistically different among both procedures. REPA average time was 105 minutes (RIC 80–130), and ETEP average time was 120 minutes (RIC 95–285) (p = 0.03).

Drains were used in every case for both groups and were extracted when the output was under 30 cc per day. In REPA, the mean time for drain extraction was 11.92 days and 8 days in ETEP (p < 0.001).

Seroma incidence (Fig. 1) was identified in 40.3% (n = 25) of the REPA cases and 5.8% (n = 5) of the ETEP procedures (p = 0.001). The median ultrasound estimated volume was 152 cc (±58.9). In the REPA group, one patient needed surgical treatment, 23 were drained by puncture, and 1 did not need further interventions. In the ETEP group, two patients needed puncture, and three patients did not require any procedure for seroma management.

In a multivariate analysis (Table 3) for seroma incidence adjusted for age, sex, BMI, type of procedure, and days of drainage, we only found that the type of procedure and the REPA technique were associated with a significant risk of its incidence [ORa 16, 67 (IC95 4.67–59.52), p < 0.001].

Hematoma was found in two cases in each group; SSI was recorded in two cases in the REPA group and three cases in the ETEP group (p = NS).

There were no conversions in the REPA group, and 3 (3.4%) were performed in the ETEP group. We found 1 recurrence in the ETEP group and 1 in the REPA group (p > 0.99). There was no mortality in the series analyzed.

Discussion

REPA and ETEP are two procedures whose popularity is growing worldwide since they do not require access into the abdominal cavity, reducing the possibility of visceral injuries and trocar hernias and allowing the usage of propylene mesh. In our experience, both surgical techniques are safe and reproducible. We objectivize a longer surgical time in the ETEP group, which could be associated with the complexity of the technique and its learning curve. The REPA group reported the need for longer drainage time usage and also a higher incidence of seroma.

Both techniques have the advantages of minimally invasive surgery accompanied by good esthetic results and are considered safe when correcting the aforementioned defects. However, it is well known that the ETEP technique is more demanding and challenging for the surgeon and requires greater skills in advanced laparoscopy than the REPA technique, which, on the other hand, is more ergonomic and reproducible. This is also reflected in our results, in which we found a significant difference in terms of surgical time, being shorter in the REPA group than in the ETEP group (105, IQR 80–130 versus 120, IQR 95–285 minutes; p = 0.03). More conversions to the open technique were also registered in the ETEP group, even though this did not reach statistical significance. Nevertheless, ETEP provided the possibility of multiple defects repair when inguinal hernias were present which is a great advantage for the technique.

In agreement with most of the published literature, the most frequent complication associated with endoscopic correction of diastasis recti and midline defects is seroma, being described in some REPA series in up to 48% of patients, ² 23%, ⁶ or 12% ⁷ or even higher, ⁸ whereas the ETEP technique reports better result regarding seroma incidence rounding 2.34%–2.5%.^9,12 In an article published by Kethan in 2021, ¹³ a high incidence of seroma associated with the ETEP technique of 12.1% (n = 7) was described, but we must clarify that, in this series of 58 patients, the use of drainage was not systematic but rather selective to those patients in whom combined TAR was performed, which could influence the results. Although in our usual practice, we do not puncture and aspirate all diagnosed seromas to avoid infectious complications, for this study, we routinely puncture and aspirate all clinically detected seromas with an aseptic technique to avoid possible interpretation errors. The differences between REPA and ETEP regarding seroma formation were statistically significant supporting the clinical practice. This is an expected outcome due to the extended subcutaneous dissection and the onlay mesh placement of REPA.

The need for conversion was recorded in 3 cases of the ETEP group (3.4%) which is like that found in the literature, varying from 2.33% ¹² to 4.5%. ¹⁴ This fact reflects the larger learning curve demanded by a technique that is more difficult to perform and reproduce than REPA. ETEP requests a clear knowledge of the abdominal wall anatomy and the development of several maneuvers like the dissection of the retromuscular space and upward suturing.

To the best of our knowledge, this is the first comparative report between REPA and ETEP. We did not find in the literature comparative studies between both techniques, although we did find comparative articles between ETEP and intraperitoneal onlay mesh (IPOM) or IPOM plus. ¹⁵ IPOM ¹⁶ was later redefined as IPOM plus when the closure of the fascial defect was associated. ¹⁷ This technique, however, has as a counterpart the risk of serious complications related to the placement of the mesh in the intraperitoneal position (adhesions, intestinal obstruction, and even fistula due to direct contact of the mesh with the intestinal loops) and high rates of chronic pain (secondary to transmural fixation of the mesh). ¹⁸ It was found that despite the longer operating time in patients undergoing ETEP, they required less hospitalization time and presented less postoperative pain since transparietal fixation of the mesh was avoided. The mesh position practically eliminates the risk of fistulas or visceral adhesions associated with intraperitoneal placement since the closure of the defect is performed after the dissection of the retromuscular space which reduces tension and pain. In addition, better cosmetic results are mentioned in the ETEP group.^19,20 Finally, the cost of the propylene mesh used in ETEP is much lower than those prepared for visceral contact needed in IPOM or IPOM plus.

A meta-analysis by Aliseda ²¹ on the short-term results of the ETEP technique for the repair of ventral defects has recently been published. For the report, 13 studies were included, and the authors conclude that in the hands of well-trained surgeons, the ETEP technique is safe and effective, with low rates of intraoperative complications, seroma, hematoma, major complications, and recurrence, although a longer surgical time was reported as it is a challenging technique for the surgeon. Robotic surgery^22,23 might be a feasible option to solve these problems based on poor ergonomics, reducing the technical difficulties for the operator while maintaining the favorable results observed.

This study does have limitations. Its retrospective nature, the lack of assessment of postoperative pain, and the lack of long-term follow-up (greater than 6 months) of patients to assess recurrence or final esthetic result. In contrast, most of the included defects were medium sized. Large defects might bias the results due to technical difficulties since they require more experience and skill. Small defects, on the other hand, might be resolved in a conventional procedure, and the results are usually very good regardless of the approach. Finally, an onlay mesh placement is not considered adequate for hernias larger than 5 cm in our department. Nevertheless, this is the first report that approached the comparison of REPA and ETEP.

As surgeons, we must not lose sight of the primary objective of repairing wall defects, which is the restoration of the anatomy and the normal physiology of the anterior abdominal wall musculature. The correction of existing hernial defects with minimal recurrence rates, good management of postoperative pain, and rapid return to daily activities, with the best possible esthetic results, are also important objectives of any technique. REPA and ETEP might be both interesting techniques that should be regarded as options for abdominal wall repair. While REPA might offer an excellent esthetic result with a more reproducible technique, it must deal with the problems of the onlay placement of the mesh and large subcutaneous dissection. Then, this might be ideal for small defects in patients who have a great interest in esthetic outcomes. ²⁴ In contrast, ETEP provides an anatomically ideal repair, with very good esthetic results, but demands more time and a larger learning curve. More comparative studies with larger sample sizes and prospective randomization are needed to clarify the precise indications of each approach.

Conclusion

REPA and ETEP are safe and reproducible and do not require access to the abdominal cavity, reducing the possibility of visceral injuries. Both approaches reported short hospitalization times and almost no major complications. We found a longer surgical time in ETEP and a higher incidence of seroma in REPA.