https://imcjms.com/public Ibrahim Medical College Journal of Medical Science https://imcjms.com/public/registration/journal_full_text/324 Thu, 20 Jun 2019 12:18:35 +0000 Abstract Background and objectives: Mesh infection following hernia repair has previously often resulted in removal of mesh. The aim of this study was to evaluate if negative pressure wound therapy (NPWT) can be used to treat such complications and preserve the mesh. Materials and method: A prospective study was carried in the Department of Surgery, BIRDEM General Hospital from January 2017 to January 2019. Patients with deep wound infection and exposed infected mesh after hernioplasty were included in the study. Patients’ demographics, existing comorbidities and outcome were recorded. All patients were treated with NPWT till the wound was covered with healthy granulation tissue and closed. Results: NPWT was used to treat 7 patients with mesh infection following hernia repair. There was 2 male and 5 female cases and age ranged from 38-58 years. With NPWT the mesh in 6 patients (86%) out of 7 could be completely salvaged and wound closed with secondary suturing. However, in 1 patient although the mesh covered with granulation tissue by NPWT and wound was closed; but it had to be partly removed later on due to development of chronic discharging sinus 20 days after stitch removal. Conclusion: The study demonstrated that NPWT was a useful technique for the treatment and preservation of infected mesh after hernia repair. IMC J Med Sci 2019; 13(1): 008. EPub date: 20 June 2019. DOI: https://doi.org/10.3329/imcjms.v13i1.42041 Address for Correspondence: Dr. Amreen Faruq, Assistant Professor, Department of Surgery, BIRDEM General Hospital, 122 Kazi Nazrul Islam Avenue, Shahbag, Dhaka 1000. E-mail: dramreen78@yahoo.com   Introduction The use of prosthetic mesh in the repair of abdominal wall hernias that occur either due to open or laparoscopic surgery is the gold standard treatment. Mesh repair significantly reduces hernia recurrence by 30 % [1-3]. However, as with any prosthetic implant the mesh is susceptible to infection. The reported incidence of mesh infection following hernia repair varies from 1% to as high as 7-8% [4-8]. The rate of mesh infection following hernia repair in our hospital is not available. The exact incidence may be difficult to find probably due to its variable presentation with symptoms starting in early postoperative period to several years after surgery. Mesh infection is a misery for the patient as it is associated with longer hospital stay, added expenditure and emotional trauma. The recommended treatment for mesh infection involving non absorbable mesh is early surgical removal of the mesh and wound care [4-10]. However, this may leave behind a more complex open wound with an abdominal wall weakness, resulting in a recurrent hernia. Negative pressure wound therapy (NPWT) is a newer technique used in the management of wound infection. This therapy enhances wound healing by (a) removing excess exudates, (b) providing a controlled moist environment, and (c) promoting neovascularization and granulation tissue formation. Moreover, it also stimulates shrinking of the wound size [11-13]. Taking into account of these properties, the present study was undertaken to evaluate the NPWT in the salvation/management of infected mesh of hernioplasty cases.   Materials and Methods This prospective study was carried out in the department of Surgery, BIRDEM General Hospital from January 2017 to January 2019. Patients included in the study were informed of the treatment options and informed written consent was obtained. Study population: All patients diagnosed with deep wound and mesh infection/exposure following hernia repair (incisional, inguinal, umbilical, paraumbilical) were included in the study. Minor superficial surgical site infection following mesh repair were excluded. Mesh infection was defined as presence of local signs of wound infection namely purulent discharge /pus or abscess formation at the level of mesh with positive microbiological culture results. Superficial surgical site infection was defined as infection that occurred within 30 days of surgery involving skin and subcutaneous tissue of incision while deep surgical site infection was defined as infection involving deep soft tissue (fascia, muscle) [14]. Information regarding age, body mass index (BMI)), presence of comorbidities , site of hernia wound and size, type of mesh used for the repair of hernia and number of days when infection occurred after hernioplasty operation were recorded in a pre-designed data sheet. Negative pressure wound therapy (NPWT): After obtaining consent, negative pressure wound therapy (NPWT) was employed for the management/ salvation of the infected mesh. NPWT procedure involved controlled application of sub-atmospheric pressure to a local environment using a sealed wound dressing connected to a vacuum pump [15]. Initially the wound size was measured and surgical debridement of the wound was done under general or spinal anesthesia. Then, wound size was again measured after debridement and NPWT applied. A sterile black sponge was cut into specific size according to shape, size and depth of the prepared wound. A tube with multiple perforations at one end was placed within the sponge ensuring that the end with perforations remained inside the sponge and the rest taken out through the sponge. The sponge was soaked in 10% povidone iodine solution and wrapped with Sofratulle (medicated Vaseline gauge) to prevent adherence of the sponge to the wound. The sponge was then placed on the wound just above the mesh; ensuring that the mesh was in firm contact with the underlying wound surface. A transparent occlusive and adhesive dressing was applied over the sponge and the tube brought out through it making sure that the dressing was airtight (Fig 1a, b, c, d). The drainage tube was connected to commercially available portable suction machine or wall mounted suction devices.   Fig-1a. Wound infection after hernioplasty (mesh repair) in an incisional hernia (arrow); 1b: Wound showing exposed mesh after debridement; 1c: NPWT dressing- Black sponge wrapped in Sofratulle being placed in wound; 1d: Airtight occlusive dressing on abdominal wound.   The negative pressure was set to-100 to- 120 mm Hg during the entire NPWT treatment. Suction was automated at 10 minutes interval. Initially the NPWT dressing was opened every third day and a new dressing given, this was done for first 2 sessions then dressing changed every 5th day or once a week depending on the wound condition. The dressing was continued till the wound and mesh was covered with healthy granulation tissue (Fig 2a and 2b). The wound was irrigated with normal saline mixed with 10% povidone iodine (3:1) once daily through the tube. Systemic antibiotics were used according to the results of culture and sensitivity.   Fig-2a. Granulation tissue formation after two sessions of NPWT; 2b: Wound and exposed mesh covered with granulation tissue.   The NPWT was continued till the mesh was covered with granulation tissue. Once the wound was covered with healthy granulation it was cleaned with normal saline and wound closure planned. The wounds were closed either by suture or skin graft depending on the size of the wounds. Healing by secondary intention was allowed in cases where suture or skin graft was not possible. After wound closure, the patients were carefully followed up till wound healed and stitches were removed. Duration of NPWT and length of total hospital stay were also recorded. Sample of wound swab was taken from each case for culture and sensitivity test. There was a follow up plan for 3 years for each patient from the time of wound closure to observe any delayed wound infection, fistula or hernia recurrence.   Results A total of 7 patients were included in this study. Out of 7 cases, 4 were patients primarily operated at BIRDEM General Hospital and 3 were referred from different hospitals after developing wound infection following hernioplasty operation. Among the study patients, 71% (5/7) were female and 29% (2/7) were male. The mean age and BMI of the study patient were 47.85±6.84 years and 30.02 ± 4.97 kg/m2 respectively. About 57% of study patients presented with incisional hernia. Incisional hernia was present mostly in older patients (>50 years) and paraumbilical hernia was present in relatively younger patients (<45 years). Polypropylene mesh was used in majority of the patients (5/7, 71%; Table-1). The mean postoperative day of diagnosis of wound infection was 7.71 ±2.56 days (range 4-11 days). Male patients developed infection earlier (< 6 post operative day) than female patients.   Table-1: Types of hernia and mesh used in study population   Table-2 describes the co-morbidities of the study patients. All the patients were diabetic. Hypertension, chronic kidney disease, bronchial asthma and hypothyroidism were present in 57.1%, 42.9%, 29% and 14% of the study patients respectively. Out 7 cases, 6 had multiple or more than one comorbidity.   Table-2: Details of co-morbidities present in all patients   Table-3 shows the pattern of bacteria isolated from the 7 cases prior to instituting NPWT. Pseudomonas sp was present in 42% patients either individually or in combination with other bacteria such as Esch. coli or Klebsiella sp. Out of 7 cases, 4 had wound infection with single bacteria while 3 had multiple organisms.   Table-3: Pattern of organisms isolated from wound samples of study cases (n=7)   Table-4 shows the size of the wound of the individual case before and after completion of NWPT. Wound size was measured after first debridement and after 3 sessions of NPWT in all patients and finally before closure. There was 22-24 % reduction in wound size after completion of NPWT in all 7 patients.   2026 Ibrahim Medical College. All rights reserved.