EXPERIMENTAL AND CLINICAL TRANSPLANTATION

Objectives: An incisional hernia seriously burdens the quality of life after liver transplant. The incidence of incisional hernia after liver transplant is reported to be 4% to 20%. Here, we evaluated incisional hernias that occurred after adult liver transplant and incisional hernias intentionally made in infant liver transplant procedures.

Materials and Methods: Between December 1988 and May 2016, we performed 536 liver transplant procedures in 515 patients. Demographic features, surgical outcomes, and predisposing factors were evaluated.

Results: Of 452 liver transplant patients included, incisional hernias were diagnosed in 29 patients (6.4%; 7 pediatric, 22 adult). Most were males (77%) with Child-Pugh score C cirrhosis (62%), moderate/severe ascites (81%), and serum albumin levels <3.5 g/L (86%). Incisional hernia developed in 16 of 51 patients (31%) with wound infection. Twelve incisional hernias were seen in 40 recipients (30%) with body mass index ≥30 kg/m². Eight of 45 patients (18%) with repeated surgery had incisional hernias. Five of 22 adult incisional hernias (23%) had primary fascia repair, and 17 (77%) were repaired with Prolene mesh graft (3 sublay, 14 onlay). No other complications and no hernia recurrence were shown during follow-up (range, 8-138 mo). Of 7 pediatric liver transplant patients with intentionally made incisional hernias during liver transplant, 5 patients had primary fascia repair and 2 patients had onlay mesh repair. No complications or recurrence were shown during follow-up (range, 12-60 mo).

Conclusions: Repeated surgery, postoperative wound infection, and obesity were found to be predisposing risk factors for incisional hernia development after liver transplant in adults. Abdomen closure in infant liver transplant with large-for-size grafts is a different area of discussion. Here, we suggest that an intentionally made incisional hernia with staged closure of the abdomen is safe and effective for graft and patient survival.

Key words : Incisional hernia, Liver transplant

Incisional hernia (IH) after liver transplant remains a serious complication, as it can greatly burden the quality of life. The incidence of IH after liver transplant is reported to be 4% to 20%.^1,2 Many studies have reported various predisposing factors for IH after liver transplant, including advanced age, obesity, wound infection, pulmonary complications, ascites, steroid use, diabetes, surgical techniques, suture material, immunosuppressive agents such as sirolimus and mycophenolate mofetil, and even lack of surgeon experience.^3,4 Liver transplant patients have a number of these risk factors. In addition, in small infants who receive large-for-size liver grafts, the discrepancy between the small abdominal cavity and large graft cause inability to provide sufficient blood supply to the liver graft, causing graft dysfunction.⁵ Thus, an IH is intentionally made to decrease the tension of the graft. In this retrospective study, we evaluated our management of IH that occurred after adult liver transplant and IH that we intentionally made in infant liver transplant procedures.

Materials and Methods

Between December 1988 and May 2016 at our centers, we performed 536 liver transplant procedures in 515 patients. We excluded patients with early postoperative mortality and procedures during the year before so that we could have a reasonable follow-up period for IH development.

In adults, a standard access for liver transplant was via transverse bilateral subcostal laparotomy with a midline extension (Mercedes incision). Exposure of the upper abdomen during transplant requires a retraction system, which causes compression of the incision margin. All biliary and vascular anastomoses were performed with loupe magnification (× 2.5). The technical details of hepatic vein, hepatic artery, and portal vein anastomoses have been described previously.^6,7 The incisions were closed in 2 layers, with the lower layer with continuous polydioxanone 1/0 sling suture with interrupted absorbable sutures and the upper layer with interrupted absorbable sutures.

In infants, we used transverse bilateral subcostal incisions for laparotomy. A retraction system was not required. Whenever possible, the incision in small infants was closed with interrupted sutures as a single layer. We based closure of the abdomen (both for fascia and skin closure, skin closure without fascial approximation, or closure with a Bogota bag) according to the intraoperative findings, perfusion of graft, and tension of the abdomen.

Ultrasonographic examination of hepatic perfusion was done intraoperatively (twice daily during the first week after surgery). At our center, routine ultrasonographic examinations are scheduled 1 month after liver transplant and at 3-months intervals thereafter. All patients received tacrolimus and mycophenolate mofetil-based immunosuppression. Methylprednisolone (10 mg/kg) was administered intraoperatively and continued postoperatively from 10 mg/kg, tapered to 0.1 mg/kg at the end of month 1, and stopped at the end of month 3.

Demographic characteristics, including body weight, graft mass and recipient body weight ratio (GBWR) for pediatric cases, Child-Pugh score, preoperative albumin levels, cause of liver disease, immunosuppression protocol, postoperative complications, comorbidities, and operative time of recipients, were collected. Surgical outcomes and predisposing factors were evaluated. Before the hernia repair, patients received perioperative antibiotics. All procedures were done under general anesthesia. A primary fascia repair was performed when edges of the fascia approximated in the midline without tension. In patients with mesh repair, mesh was tailored according to the defect so that at least 2 to 3 cm of mesh overlapped the edges of the fascia. If possible, we preferred to close the peritoneum with absorbable sutures before fixation of the mesh.

After exclusion of patients with early postoperative mortality and liver transplant procedures during the previous year (so that a reasonable period for developing IH could occur), our retrospective study included 452 liver transplant patients (207 pediatric, 245 adult). Incisional hernia was diagnosed in 29 patients (6.4%), which included 7 pediatric and 22 adult liver transplant recipients.

Of the 245 adult liver transplant recipients included in our study, 22 received IH repairs (age range, 31-62 y). Demographic features and associated factors are shown in Table 1. Most of the patients were males (77%) with Child-Pugh score of C cirrhosis (62%), moderate/severe ascites (81%), and serum albumin levels lower than 3.5g/L (86%). Incisional hernia developed in 16 of the 51 patients (31%) with wound infection. Twelve of 40 patients (30%) with body mass index of ≥ 30 kg/m2 had IH repair. Eight of 45 patients (18%) with repeated surgery had IH. Of 22 adult patients with IH, 5 (23%) had primary fascia repair and 17 (77%) had repair with Prolene mesh graft (3 sublay, 14 onlay). All 5 primary repaired IHs were small (<5 cm), were midline IHs, and were repaired safely after fascia closure. However, the remaining 17 were larger defects (12 IH between 5 and 10 cm, 5 IH > 10 cm); therefore, tension-free repair with Prolene mesh was preferred. Three patients had seroma, and 1 patient had subcutaneous hemorrhage during the early postoperative period after IH repair (18%). We had no other complications and no hernia recurrence during our follow-up of these patients (range, 8-138 mo).

Of 207 pediatric liver transplant procedures retrospectively evaluated in our study, 58 patients (35 male, 23 female) had body weight < 10 kg (mean weight was 7.8 ± 1.44 kg; range, 4-10 kg) and GBWR > 4%. All of these patients had living-donor liver transplants. Our data showed 18 patients who received large-for-size grafts. After fascia was closed, all patients had graft perfusion complications; therefore, we intentionally implemented hernias in all of them. We closed only skin in 11 patients, and we closed abdomen with Bogota bag in 7 patients (2 patients were closed with Bogota bag at the first operation, 5 patients were reoperated and closed with Bogota bag due to vascular problems and abdominal hypertension). All abdomens for Bogota bag patients were closed in 2 weeks. One patient died due to major abdominal infection and sepsis.

Intentional IH repair was made in 7 pediatric patients (6 males, 1 female) after the first year of liver transplant (range, 12-15 mo). All 7 of these patients had body weight < 6 kg (range, 4-6 kg) and GBWR > 4%. All 7 patients received left lateral segments from their living donors. Biliary atresia was the most common cause of liver failure (5 biliary atresia, 2 fulminant hepatic failure). In all patients, dissection of the skin layer, including subcutaneous tissue from the fascial layer, was extended sufficiently to the area peripheral to the hernia. After dissection, approximation of the fascia was primarily possible in all 7 patients.

Of the 7 liver transplant patients with intentional IH repair, 5 received primary fascia repair and 2 received onlay mesh repair. None of these patients had any complications or recurrence during follow-up (range, 12-60 mo).

An IH after liver transplant is a serious complication with a reported incidence of 4% to 34%.^1,2In our study, we reported a relatively low incidence (6.4%) versus that shown in previous reports. Several predisposing factors for IH after major abdominal surgery are similar to those shown in liver transplant patients. These include obesity, patient age > 45 years, chronic obstructive pulmonary disease, preoperative low albumin levels, anemia, previous abdominal surgery, and postoperative wound infection.^8,9 Incidence of IH after liver transplant is similar to IH after major abdominal surgery (11%-23%). In our patients, obesity, wound infection, and repeated surgery were also predisposing factors for IH. In the literature, avoidance of classic Mercedes incision is associated with lower incidence of IH.¹⁰ Although our standard access for liver transplant in adults is via transverse bilateral subcostal laparotomy with a midline extension (Mercedes incision), we have less incidence of IH than in the literature. End-stage liver disease, postoperative and preoperative ascites, corticosteroid bolus therapy for rejection episodes, and immunosuppression with mycophenolate mofetil or sirolimus have significant effects on IH development.¹¹ In advanced liver cirrhosis, presence of ascites due to portal hypertension leads to weakening of the abdominal wall, thus leading to development of IH.³ The use of Prolene mesh grafts in hernia repair has been strongly linked to reduced hernia recurrence rates in nontransplant patients. However, the rate of wound infection is reported to be higher than with simple suture repair.¹² We used Prolene mesh grafts in 83% of our patients, and we had no reports of wound infection or hernia recurrence (Figure 1).

Intentionally made IH in infant liver transplant is a different entity. In pediatric liver transplant, the use of large-for-size grafts (GBWR > 4%) may cause graft damage such as vascular complications and necrosis due to insufficient blood supply to the graft.^13,14 Reduction of the graft has been used in several centers. However, it has some disadvantages for both the donor (in case of in situ reduction) and the recipient. For the recipient, there are increased risks of biliary leakage, impaired venous drainage, and longer cold ischemia time (in case of graft reduction at back table).¹⁵ Temporary abdominal closure using prosthetic materials has been reported in pediatric liver transplant.^16,17Such prosthetic materials are associated with increased risk of infection. Bioengineered skin equivalents have also been used for management of large abdominal skin defects. However, these are not available in many centers.¹⁸ In our center, we prefer to make intentional IH in infant liver transplant patients. We prefer the Bogota bag technique or skin closure without fascia closure, and we believe these methods are safe and effective to avoid abdominal compartment syndrome. As shown in our study patients, after the first year of liver transplant, we repaired IH in 7 infants (with body weight < 6 kg at the time of liver transplant). None of these patients had any complications or recurrence during follow-up (range, 12-60 mo) (Figure 2).

Several predisposing factors for IH after major abdominal surgery are similar to those shown in liver transplant patients. In our study, repeated surgery, postoperative wound infection, and obesity were found to be predisposing risk factors for IH development after liver transplant in adults. Primary repair of small and midline IHs can be done safely if fascia closure is possible; however, for larger defects and especially subcostal IH tension-free repair, use of Prolene mesh is preferred. Abdomen closure in infant liver transplant with the use of large-for-size grafts is a different subject of debate. Complications associated with size-mismatched large grafts include inability to localize the graft in the small abdominal cavity of the recipient and inability to provide sufficient blood supply to the liver graft. Further reports are needed that describe detailed repair procedures for infant recipients.

Volume: 15 Issue: 1 February 2017 - Supplement - 1

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