Laparoscopic surgery requires intensive training and a high degree of manual and technical skill. Today, ventral and incisional abdominal wall hernias are increasingly treated by laparoscopic placement of an intraperitoneal onlay mesh (IPOM). In the last few years, minimally invasive surgery has continued to develop, further reducing abdominal wall trauma.

The major benefits of natural orifice transluminal endoscopic surgery (NOTES) include less postoperative pain, faster patient recovery and quicker return to the workplace and daily activities, as well as improved cosmesis [1]. The advantages of NOTES are mostly due to the avoidance of fascial trauma. When considering known complications of trocar hernias, an abdominal wall access alone might be a risk factor for hernia recurrence following traditional laparoscopic procedures. NOTES procedures can be divided in pure NOTES and hybrid NOTES interventions. For the hybrid NOTES technique, an additional umbilical trocar is performed for increased safety during the insertion of trocars through natural orifices.

The aim of this study was to assess the feasibility and safety of a hybrid NOTES technique in abdominal wall hernia repair. We aimed to minimize abdominal wall trauma during surgery, reducing secondary trocar site-related complications, such as pain, surgical site infections and trocar site hernia formation. We wanted to improve cosmesis and patient satisfaction.

Methods

This cohort study was conducted in a single center and was analyzed retrospectively. Between September 2011 and December 2012, we performed six laparoscopic-assisted transvaginal IPOM procedures. Before surgery, all patients underwent a gynecological examination. The patients agreed to IPOM repair via transvaginal approach, and written informed consent for surgery was obtained. The transvaginal access was approved by the IRB.

On the operating table, the patient was laid in modified lithotomy position, enabling transvaginal as well as the traditional laparoscopic approach. The patient was draped in standard sterile fashion, using betadine solution for the genital region and betaseptic solution for the abdomen. The urinary bladder was emptied using a single-use catheter at the beginning of the procedure. Antibiotic prophylaxis was assured with insertion of a 500 mg metronidazole ovule into the vagina before bedtime the evening before surgery and with 1.5 g of cefuroxime intravenous within 30 min prior to incision. General anesthesia was mandatory.

Pneumoperitoneum was established with a Veress needle at the umbilicus. CO2 was insufflated to a pressure of 12–14 mmHg. The transumbilical access was subsequently dilated to 5 mm (VersaStep, Covidien, Dublin, Ireland), and a 5-mm 30° laparoscope was inserted. The patient was then switched to the Trendelenburg position. The transvaginal trocars were inserted under laparoscopic view (12-mm VersaStep plus, Covidien, Dublin, Ireland and 5 mm flexible access) behind the cervix into the pouch of Douglas (posterior colpotomy). The second 10-mm 30° camera was inserted through the 12-mm transvaginal trocar. The falciform ligament, ligamentum teres and preperitoneal fat tissue around the hernia were dissected with electrosurgical cutting devices for optimal placement and proper fixation of the mesh in the fascia. The dissected fat tissue was removed using an Endobag specimen retrieval system. A lightweight composite mesh (Physiomesh, Ethicon, Somerville, NJ, USA) was then introduced into the abdominal cavity through the 12-mm transvaginal trocar, positioned centrally and fixed with absorbable tacks (AbsorbaTack™ Fixation Device, Covidien, Dublin, Ireland, or Ethicon SecureStrap™ Fixation Device, Johnson & Johnson, Cincinnati, OH, USA) using double-crown technique and overlapping the margin of the hernia opening with 5 cm of mesh. During mesh fixation, the pneumoperitoneum was reduced to 8–9 mmHg. Pressure was subsequently restored to 12–14 mmHg. We inspected the abdomen for hemostasis and removed all trocars. After evacuation of the pneumoperitoneum, no suturing of the abdominal wound was necessary, apart from skin closure (Monocryl 4-0, Ethicon, Somerville, NJ, USA). The 12-mm vaginal access was closed with absorbable sutures (coated Vicryl 2-0, Ethicon, Somerville, NJ, USA). The 5-mm vaginal wound did not require any further care. Every procedure was meticulously recorded with digital videodisc. Our surgical procedures fulfilled the high requirements of the International Endo Hernia Society (IEHS) and recently appeared in Surgical Endoscopy and Other Interventional Techniques [2].

In case of umbilical hernia, the first trocar was placed through the hernia opening. After insertion of the two transvaginal trocars under visualization, the transumbilical trocar could be removed. The rest of the procedure was performed in one-hand technique transvaginally with 5-mm instruments under transvaginal view, using a 10-mm 30° laparoscope. No additional abdominal trocar was necessary.

All patients were scheduled as inpatients. The analgesia was routinely assured by 4 g paracetamol and metamizole daily fix and 200 mg tramadol in reserve. Demissio was accorded by sufficient analgesia and evacuation of the bowels. In addition to normal postoperative surgical consultation, patients were seen by a gynecologist 3 weeks post-surgery.

Results

From September 2011 to December 2012, we selected six patients for laparoscopic-assisted transvaginal IPOM procedures. All patients agreed to the intervention via a transvaginal approach. In this initial phase, only patients with small or medium primary abdominal wall hernia openings were selected (max. 3 cm in diameter). Based on the European Hernia Society (EHS) classification for primary and incisional abdominal wall hernias, we repaired one epigastric, three umbilical and two combined epigastric and umbilical hernias [3]. Median age was 50 years (range 33–62 years). Median body mass index was 22.4 kg/m2 (range 19.5–37.1 kg/m2). Five patients had undergone previous abdominal surgery (one laparoscopic-assisted rectosigmoid resection, one direct closure of an umbilical hernia and two open inguinal hernia mesh repairs) and/or gynecological surgery (two Caesarian sections and two vaginal hysterectomies). Median operative time was 67 min (range 30–90 min.). Only one minor complication occurred perioperatively. A second-degree skin burn to the labia majora was observed. This incident was due to a damaged isolation of a grasper. Median hospital stay was 3 days (range 2–6 days).

Outpatient control: The patients underwent an examination by a gynecological specialist 3 weeks post-surgery. No gynecological complications or dyspareunia were recorded. A follow-up consultation was organized at our institution (median 15 months, range 5.5–20 months). One recurrence occurred in the case of the patient with 37.1 kg/m2 body mass index, implanted mesh of 25 × 20 cm and with combined hernia opening, epigastric (1.5 cm, small) and umbilical (3 cm, medium). No infection and no mortality were recorded.

Discussion

Since the first transvaginal cholecystectomy, surgical techniques that do not cause scarring have developed quickly [4]. In 2009, Jacobsen et al. [5] published the first case report of NOTES IPOM, followed by Bruna [6]. Last year, Wood published a small case series of six pure transvaginal ventral hernia repair procedures performed between November 2010 and February 2012 [7]. Others publications are known, but these describe transvaginal hernia repair in animals [8–11]. The IEHS even designated a chapter to the new technological developments in part 3 of the recently published Guidelines for laparoscopic treatment of ventral and incisional abdominal wall hernias [12].

Our study has evident limitations, for example the retrospective design, the bias in patient selection and the small number of patients operated on with this innovative technique. However, we believe to be reporting the largest case series of hybrid transvaginal abdominal wall hernia repair in humans.

More practice in transvaginal surgery is required to ensure increased safety and the dexterity needed for this innovative method for IPOM. To date, we have completed over 500 hybrid NOTES transvaginal cholecystectomies at our institution. Despite our high level of expertise in transvaginal cholecystectomy and laparoscopic IPOM, we only selected small and medium hernias in an elective setting for this initial phase of hernia repair in NOTES technique.

As for transvaginal cholecystectomy, we always introduce the vaginal accesses under visual control through a 5-mm abdominal trocar. We agree with other authors that a blind insertion of trocar transvaginally would be too uncertain or present unnecessary danger to the patient [5, 13]. Safety has priority. However, this point of view remains contested [14].

The outcome of hernia repairs is calculated by recurrence, postoperative chronic pain and complications. The recurrence rate is probably the most critical parameter in terms of quality control. The recurrence rate for laparoscopic IPOM is similar to open ventral hernia repair [15].

Studies on trocar site hernia following surgery are mostly conducted on patients following laparoscopic cholecystectomy. Known patient-related risk factors are older age, high body mass index and diabetes. Hernia-related risk factors are recurrent hernia, intraoperative enlargement of trocar site for specimen extraction and postoperative surgical site infection [16, 17]. The use of large-size trocars (over 10 mm) and their insertion along the abdominal midline are also two of the greatest risk factors for developing a new hernia. A 5-mm trocar used in the abdomen does not seem to increase the risk of hernia [18].

In the review by Bunting with a large collective (5984 patients), the overall incidence of trocar site hernia was 1.7 %. However, the follow-up time of the seven included studies was very heterogeneous (range 1 month–5 years) [16]. In a more recently published single-center study on 241 patients with 3-year follow-up, the incidence of trocar site hernia rose to 25.9 % [17].

Such studies reinforced our conviction, on the one hand, that transvaginal cholecystectomy is a suitable approach and, on the other hand, that transvaginal abdominal wall hernia repair could be appropriate for future procedures.

One patient experienced a recurrence in our sample. The patient had a body mass index of 37.1 kg/m2, an established risk factor according to IEHS guidelines (level 2B statement) [2]. Hers was the largest hernia opening of all the selected patients. It was a combined small epigastric (1.5 cm) and medium umbilical (3 cm) hernia, 8 cm removed from each other. The defects were covered with the biggest mesh (25 × 20 cm) of the group. Here again, in accordance with the IEHS guidelines for hernia repair in obese patients, we created a 5-cm overlap and used transfascial sutures as well as tacks with double-crown technique for mesh fixation [2]. There were no complications or technical problems during surgery. The patient was reoperated 19 months later. The mesh was adherent to the omentum majus in the epigastrium. In other words, non-ingrowth of the mesh with the abdominal wall was observed. The transfascial sutures were still in the correct initial position. We cut the mesh, closed the gap with permanent sutures and applied another mesh to cover the epigastric recurrence using the laparoscopic IPOM technique.

Laparoscopic hernia repairs lead to lower incidence of surgical site infections than open procedures [15]. Heniford reported an overall infection rate of 1.8 % in a 9-year follow-up of 850 laparoscopic ventral hernia repairs [19]. In contrast to open surgery, a surgical site infection after laparoscopy does not indicate mesh infection and does not automatically require mesh removal. The non-inferiority of the transvaginal approach for abdominal wall hernia mesh repair must be investigated further.

Linke and Zerz et al. [20] demonstrated that vaginal disinfection significantly decreased vaginal bacterial load, leading mostly to sterile vaginal culture. In others studies on animals and humans, results demonstrated that transvaginal access for peritoneoscopy, peritoneal and liver biopsy or synthetic mesh placement could be superior in terms of sterility than if performed classically through skin incisions [21, 22]. Another study in NOTES transgastric hernia repair demonstrated a significant reduction in the percentage of contaminated surface area if the mesh insertion was performed with a modified esophageal stent delivery system, minimizing contact. Without protection, contamination was increased over 6000 times [8]. Therefore, the use of a protective device is essential to avoid mesh-skin and mesh-mucosa contact.

Sexual function and fertility are of greatest interest after transvaginal NOTES procedures [23]. Of sexually active patients, 95.5 % in the prospective, single-center, cohort study of Linke and Zerz [24] would agree to undergo the same procedure with a transvaginal approach again, especially young nulliparous women.

Conclusion

The hybrid NOTES technique in abdominal wall hernia repair not only offers the advantages of pure NOTES procedures, for example minimal abdominal wall trauma and any related complications as well as better cosmesis, but also improves cosmesis and patient satisfaction. The hybrid NOTES technique guarantees safety comparable to traditional laparoscopic hernia surgery during the insertion of trocars.

Thereby, laparoscopic-assisted transvaginal IPOM is a feasible alternative to treat abdominal wall hernias. No definite conclusion can be made regarding the presumed non-inferiority of this technique in terms of recurrence and mesh infection compared with traditional laparoscopic IPOM, but we believe it to be effective and reliable. Further investigation and prospective clinical trials are mandatory.