A modified Chevrel technique for ventral hernia repair: long-term results of a single centre cohort

Quality of life (QoL) measurements were performed with a validated Dutch version of the Carolina Comfort Scale (CCS), a hernia-specific QoL questionnaire consisting of 23 items [9, 11]. The focus of the CCS is mesh-related pain, mesh feeling, and movement limitation. The maximum score is 115 points and reflects the worst possible QoL, the minimum score is 0 and equals perfect QoL. In addition to the ‘overall’ QoL, the CCS reports three subdomains, ‘mesh sensation’, ‘pain’, and ‘movement impairment’. The maximum score per subdomain is 40 points for ‘mesh sensation’ and ‘pain’, and 35 points for ‘movement impairment’. All living patients without a reoperation for a registered recurrence were contacted by letter during July 2015 to participate in the postoperative QoL evaluation. At that time, all patients were at least 3 years postoperative.

Antibiotic prophylaxis [Cefuroxime (Kefzol^®) 1500 mg] is given intravenously. Following excision of the midline scar tissue, the hernia sac is opened and adhesiolysis is performed to facilitate movement and stretching of the abdominal wall along the abdominal content. The skin and subcutaneous tissue above the anterior rectus abdominis fascia are dissected until 2–3 cm medial of the lateral border of the rectus muscles, exposing the anterior rectus fascia. Depending on the width of the hernia, an elliptical incision is made in the anterior rectus fascia mostly between 2 and 5 cm from the medial edge of the rectus muscle. The medial part of the anterior rectus fascia is separated from the muscle fibres and tendinous intersections, and ‘turned over’ towards the midline. This procedure is repeated at the contralateral side. Any residue of the hernia sac is left alone or excised. Both the left and right ‘turned over’ anterior fascia can now be sutured in the midline with a continuous 2/0 polydioxanone (PDS) suture using small bites [13]. This suture ‘closes’ the abdomen and provides the first ‘layer’ of the repair (Fig. 1). Any small defect in this new posterior layer is closed with an absorbable suture. The second layer is formed by a polypropylene mesh (Prolene^®, Ethicon Inc.; see Table 1 for mesh details) sutured to the edge of the lateral part of the anterior fascia using two long double needled Prolene^® 2/0 sutures. One tied suture fixes the mesh at the cranial and one at the caudal meeting point of the left and right lateral part of the anterior rectus fascia. With small bites the mesh is sutured to the edge of the anterior fascia running from cranial and caudal, thereafter, meeting halfway where the cranial and caudal suture are tied together (Fig. 2). During this procedure, some tension is given on the suture line so the lateral abdominal wall muscles are stretched slightly. By manipulation of the tension and size of the mesh it is possible to influence the contour of the abdomen. The mesh must lay flat on the rectus muscle without any folds. Then the excess mesh is trimmed with scissors to leave a rim of approximately 1.5 cm lateral to the continuous suture. This rim is then sutured to the ventral side of the anterior rectus fascia using single Prolene^® 2/0 sutures. Some tailoring is necessary to provide a flat 1.5 cm overlap where connective tissue can grow into the mesh (Fig. 2). Two low-vacuum drains are placed in the subcutaneous space. The subcutaneous tissue and skin are closed with resorbable continuous sutures. The drains are removed when the production is less than 50 ml/24 h, mostly within 3 days. Patients with epidural analgesia are mobilised after removal of the catheter, approximately 2–4 days postoperative. All other patients are stimulated to walk the first postoperative day. Patients are advised to wear a comfortable abdominal binder for four weeks to prevent seroma formation. Normal daily activities are permitted, though heavy lifting was discouraged for 6 weeks.

To correctly interpret the results of this study, and make any comparison to the existing body of evidence concerning the original and modified Chevrel techniques, a literature study was performed. The following databases (PubMed, Cochrane database, Google scholar, Medline, EBSCO) were searched using the following terms: ‘anterior fascia turnover’ OR ‘Chevrel method’ OR ‘Chevrel technique’ OR ‘anterior’ OR ‘frontal’ OR ‘fascia flip’ OR ‘shoelace technique’ AND ‘postoperative complications [MESH]’ OR ‘recurrence’ OR ‘hernia repair’ OR ‘hospital stay’.

All studies reporting postoperative complications, recurrence rate, or hospital stay after ventral hernia repair using either the original or modified Chevrel techniques with anterior fascia turnover were included. Only studies in English, French, Dutch, or German that accurately described the operation technique or referenced an article that described the operation technique and the exact limits of the subcutaneous dissection were included. No limitations to the year of publication were applied.

All data was analysed using SPSS statistics for Windows, IBM corp. Armonk, NY, released 2013. Baseline characteristics, response rates, and recurrence rates were analysed using descriptive statistics. Statistical significance (α) was set at 0.05. Group comparisons were performed using independent samples Student’s t test or Mann–Whitney U tests depending on the (non)parametric distribution of the data (Levene’s test for equality). Correlations between VHWG and SSOs were calculated using bivariate correlations and expressed as Pearsons ‘r’.

During the first thirty postoperative days, 30 mild (CDC grade I–II) complications and nine severe (CDC grade III–IV) complications occurred in 36 patients (23.2%) that underwent a modified Chevrel repair (Table 3). Thirty-one SSOs were observed in 30 patients (19.4%), of which the majority was seroma’s (16 patients 10.3%). Eight seromas required fine needle-aspiration, one was drained under local anaesthetic, five required reinterventions (including two reinterventions 1 year postoperative due to recurrent seroma formation), and two disappeared spontaneously. Three of the nine severe complications within 30 days were seroma’s requiring reintervention, two were abscesses, two were severe wound infections, one was a postoperative bleeding, and one was an anastomotic leakage in a patient with concomitant ileostomy takedown. The revision of the anastomotic leakage was complicated by a massive bleeding, though after re-intervention an uneventful recovery followed.

The VHWG classification identified three groups within the population (grade I Low risk, 41% (n = 63); grade II Co-Morbid, 54% (n = 84); grade III Contaminated, 5% (n = 8)). Complications occurred more frequently in the grade II and III patients. SSOs occurred significantly more with an increasing VHWG grade (r = 0.209 p = 0.009; x ² p = 0.017). Within the VHWG grading scale or the overall population there were no statistically significant differences in the incidence of complications in hernias over or under 10 cm in width (p = 0.192).

Ten patients (6%) reported persisting localized pain near the rim of the mesh, approximately 1 month postoperative. All these patients received one or more local anaesthetic injections (Lidocaine 1–2%) that relieved their pain sufficiently.

One patient with a severe wound infection was, after drainage, treated with vacuum assisted therapy, though developed a mesh infection more than 30 days postoperative, and later a recurrent hernia. Another patient, with correction of an enterocutaneous fistula as a concomitant procedure, developed a new enterocutaneous fistula after 10 months, perhaps due to erosion or infection of a small part of the mesh. The wound healed after resection of the infected part of the mesh, without finding a bowel defect. Two patients with recurrent seroma formation needed surgical intervention after 1 and 2 years, respectively. Yet another patient developed a suture fistula 16 months postoperative. After excision of a Prolene^® suture, the wound healed.

The following methods were used for assessment of recurrence: clinical examination by the surgeon as retrieved from the patient’s medical record which specifically described the condition of the abdominal wall (77%), abdominal CT-scans (13%), and abdominal wall ultrasounds (10%). The overall median follow-up for the total cohort was 34 months (range 0–128 months, interquartile range 8–62 months). Forty-five of the 155 patients had a follow-up shorter than 12 months and were not included in the long-term recurrences analysis. In this group of 45 patients no recurrences occurred. The remaining 110 patients had a median follow-up of 52 months (range 12–128 months, interquartile range 31–72 months), two of these patients developed a recurrence (1.8%) after 13 and 15 months postoperative. Both patients had a large hernia (width ≥ 10 cm). The first patient received a Vypro I^® mesh (large pore polypropylene with polyglactin, Ethicon Inc.) which failed after 13 months. During the re-intervention, it became apparent that the mesh was torn in half. The second patient had a postoperative wound infection that was initially treated with vacuum-assisted therapy, though later progressed into a mesh infection that was treated by removing the infected part of the mesh. Initially, this resolved the problem of the infection, though over time the patient developed a recurrent hernia.

Twenty-two studies were identified through the database search, and four articles were identified through cross-reference (last search performed November 2016). A total of 26 articles were screened for eligibility. Fifteen studies were excluded, one due to language restrictions, and 14 because they did not meet the inclusion criteria. Finally, ten studies (eleven including the current series) were included (Fig. 3; Table 4) [7, 8, 15]. Studies were divided in two groups, the original Chevrel technique and the modified Chevrel techniques, depending on the overlap of the mesh and the amount of subcutaneous dissection. The modified Chevrel repairs used a trimmed mesh and no subcutaneous dissection lateral of the anterior rectus sheath.

The current evidence as displayed in Table 4 consists of multiple small case series with heterogeneous populations in term of hernia size, location, origin, complexity, and follow-up method. The median and average follow-up varies between the studies, though is mostly longer than 1 year.

Wound complication rates varied from 0 to 25% in the modified Chevrel group, and from 9 to 44% in de original Chevrel group. Hospital stay was slightly shorter in the modified Chevrel group (5–6 vs. 5–11 days). The recurrence rates in the modified Chevrel group were 0–2% compared to 0–33% in the original group, though the defect size in two of the five studies describing the modified Chevrel technique were not measured objectively.

Based on the limited evidence available, the results of the current series are comparable with previously published studies of the modified Chevrel techniques. Previous studies have never reported any recurrences using the modified Chevrel technique. This could be due to the relative short follow-up, retrospective methodology, small populations, or due to publication bias, though, considering the low recurrence rate in the current series, recurrences are rare after a modified Chevrel technique.