USE OF VACUUM-ASSISTED CLOSURE (VAC) IN COMPLICATED PERINEAL WOUNDS: ANALYSIS OF CASES

Treatment of perineal wounds has been one of the challenges of surgery since its inception. Vacuum-assisted closure provides a new option that can be used in concert with a wide variety of standard existing surgical techniques. It was originally developed for treatment of chronic wounds in patients with diabetes. It has rapidly evolved into a widely accepted treatment also for acute, contaminated and complicated wounds from failed operations. User-friendliness of the technique and a high rate of success have promoted its use in all surgical specialties. One of the greatest achievements of modified technique is undoubtedly improvement in the treatment of open abdomen. Use of vacuum-assisted closure techniques in large contaminated abdominal and perineal wounds even in the presence of the artificial material like meshes has gained widespread acceptance among surgeons. Creative surgeons continue to regularly adapt the technique to difficult clinical problems. Perineal wounds present a special challenge. The vacuum-assisted closure device allows earlier wound closure, early skin grafting and hospital discharge. Its use in the perineum presents a challenge, but with proper application, even the most complex perineal wounds can be healed. We present four cases of complex perineal wounds in which the vacuum-assisted closure device was used. In experienced surgical hands, it greatly enhances the scope and safety of wound treatment. Acta Medica Medianae 2015;54(1):81-86.


Introduction
Perineal wounds present a special challenge for treatment. Vacuum-assisted closure (VAC) is a promising approach for the management of complex abdominal and perineal wounds. We present theoretical basis and cases of complicated perineal wounds in which the VAC was used.
The vacuum-assisted closure device (VAC, KCI, Inc., San Antonio, Texas, USA) has in many ways revolutionized wound care. It can be used on almost any part of the body to improve the wound healing, granulation, and decrease the time burden of wound care specialists. Perineal wounds are complex. It is often difficult to keep a dressing in place. Anatomic characteristics with presence of natural orifices of urethra and anus add to the complexity of wound management in this region. Perineal wounds are also often the result of poor healing secondary to radiation therapy for pelvic malignancies. As such, the VAC device has significant utility in overcoming these issues.
The VAC device and different dressings increase the deposition of granulation tissue with stimulation of angiogenesis, removes exudates, securely covers the wound, reduces bacterial contamination and thus decreases the time to wound healing (1).The VAC system allows earlier wound closure, early skin grafting with improved graft adherence, earlier hospital discharge, and earlier return to baseline functional status. Its use in the perineum presents a challenge, but with proper application, even the most complex perineal wounds can be healed (2). Multiple factors affect the healing of perineal wounds. In addition to ensuring adequate nutrition, prevention of excessive pressure, redirection of urinary and fecal flow, appropriate debridement, the healing of wounds in the perineum still present multiple challenges (3). High energy pelvic trauma, Fournier gangrene or necrotizing fasciitis and mesh infection in prosthetic repair are only few of the conditions where VAC can improve patient's outcome or even can save his/her life.
Pelvic fractures with critical soft tissue conditions are usually the result of high-energy www.medfak.ni.ac.rs/amm trauma. Open pelvic fractures are rare and amount to 2-4% of all pelvic fractures only. The high mortality of open pelvic injuries is due to two complications: in the early phase, the patient is endangered by exsanguination and in the following course the sepsis determines the lethal outcome (4). Open fractures require early aggressive debridement of the soft tissues followed by skeletal stabilization. Temporary wound dressings should remain in place until definitive soft-tissue coverage is obtained. Definitive soft-tissue closure will be expedited by serial debridements (5). The use of VAC as a temporary wound dressing in open fracture situations, in patients whose general condition is often severely compromised, was described as a method for bridging till definitive care of the wound (6).
Fournier gangrene is a rare but highly infectious disease characterized by fulminant necrotizing fasciitis involving the genital and perineal regions. (7) The pathology was first described in 1883 by Jean Alfred Fournier who presented five male diabetic patients with fulminating gangrene of the genitalia (8). It is a synergistic infection caused by a mixture of aerobic and anaerobic organisms and predisposing factors, including diabetes mellitus, alcoholism, malnutrition, and low socioeconomic status. Fournier's gangrene is caused by normal skin commensals of the perineum and genitalia that act synergistically to cause infection and invade the tissue, causing microthrombosis of the small subcutaneous vessels leading to ischemia. Various cytotoxic agents, collagenases, streptokinases and others are released at the site of gangrene and cause the progressive destruction of local tissue. Therefore, good management is based on aggres-sive debridement, broad-spectrum antibiotic therapy, and intensive supportive care (9). VAC is a widely adopted technique in many clinical settings. Nevertheless, its application and effect in the treatment of Fournier gangrene are still unclear although the results in treatment of necrotizing fasciitis are promising (7).
Deep surgical site infection following mesh graft repair of inguinal or incisional hernia is a serious challenge for both patients and surgeons. Most authors recommend removal of the infected mesh if the infection cannot be resolved by conservative means and/or antibiotic therapy. However, mesh removal often results in hernia recurrence, necessitating subsequent surgical procedures such as autologous flap reconstruction or another mesh graft implantation after the infection has resolved. Therefore, salvage of the infected mesh graft without surgical removal is desired. Only a few publications described mesh graft-preserving treatment by conservative means and VAC applications. With use of VAC, up to 92% mesh infections were cured depending mostly on the type of mesh used (10).

Methods
We have been using the VAC system (KCI, Inc., San Antonio, Texas, USA) for the treatment of complex perineal wounds since 2002, and VAC ULTA system (KCI, Inc., San Antonio, Texas, USA) since 2012. The VAC system consisted of polyurethane soft sponge cut to fit the wound and placed into the cavity and of a transparent occlusive gas-and fluid-impermeable plastic film applied over the foam to create an airtight seal. A hole of 2cm in diameter was cut into the film in the middle of the foam. A TRAC pad was embedded over the hole and attached to an adjustable vacuum pump by means of a suction tube. A continuous topic negative pressure of 125mmHg was used. In cases where we used VAC ULTA system for instillation we applied 0,9% saline solution in clean wounds or Prontosan ® (B. Braun, Melsungen, Germany) in infected wounds and where artificial material was involved. The cycle of instillation was set to 25min and negative pressure lasted for 4 to 6 hours. Dressing changes were performed every 48-72 hours. Besides VAC therapy, we manage these patients as follows: a Foley catheter is placed except in patients with urethral injuries where cystostomy is performed. In all patients who experience large perineal tissue loss and have a high risk of contamination, a protective ostomy is performed. The infective load of the colon and rectum is reduced with rectal washout and anal sphincter is evaluated. VAC therapy is started immediately after necrectomy and ostomy are performed. VAC and dressing changes are performed under sterile conditions in the operating room once every 2-3 days. Special care is taken to protect the nearby skin. In perineal region we always applied continuous topical negative pressure of 125-mmHg to the treated area. VAC application was continued until the wound was closed with delayed primary closure, by split thickness grafts or free flap performed by plastic surgeon.

Case 1
A 45-year-old female, who was injured in mass traffic accident, presented at the emergency room with traumatic hemipelvectomy and hemorrhagic shock. Hemodynamically unstable patient was after resuscitation submitted to a damage control procedure in the operating room (OR) where she underwent haemostasis with sutures of external iliac vessels and emergency debridement of the necrotic skin, subcutaneous tissues and lose bone fragments were removed. We used VAC black sponge and continuous topical negative pressure of 175mmHg was applied. Afterwards she was transferred to the ICU and topical negative pressure was after 3 hours lowered to 125mmHg. The patient underwent repeated exploration and debridement (Figure 1) of the wound in OR under general anesthesia on day two and four. On day six, VAC dressing was changed in ICU ( Figure 2). Bacterial samples were collected from the wound during the reoperations and dressing change. According to the bacterial clearance the wound was free of bacterial growth after the sixth day. Patient was transferred to department of plastic and reconstructive surgery where defect was covered with free flap. Patient was soon after the last procedure transferred to her nativecountry (Italy) and was not available for a follow-up.

Case 2
A 65-year old obese woman with type 2 diabetes and arterial hypertension presented to the abdominal outpatient department with a 1-day history of increasing left hip and suprapubic pain. She had a past history of abdominoplasty 10years prior to this admission. On examination, the patient was dehydrated and body temperature was elevated (38.9°C). Her blood pressure was 90/56  The patient underwent repeated exploration, debride-ment of the wound and VAC dressing application in OR under general anaesthesia on postoperative days 2,4,6. On days 9,12,15 we performed dres-sing changes. On the 20 th postoperative day, partial skin grafts obtained from the antero-lateral aspect of the right thigh were applied to the abdominal and thigh wounds. The VAC system was then applied over the skin graft at a lower topical negative pressure of 50mmHg. The patient was discharged on the 29 th postoperative day. She remained well 18-months after discharge, but she was not available for a follow-up in last three years.

Case 3
A 55-year-old male patient was admitted with a perianal gluteal abscess followed by a spread of the infection to the swollen, edematous, emphysematous scrotum. Surgical debridement and fasciotomy were performed after admission. The infection was caused by aerobic and anaerobic organisms. On the basis of the microbiological culture, the patient was given multiple antibiotic therapies. After ten days, the exudate was not completely controlled with modern dressing changes and negative pressure wound therapy was started. VAC was applied on the surface of the scrotal and gluteal area and continued for 10 days, with dressing changes every 3 days. Treatment was effective, granulation tissue appeared and the patient did not require reconstructive surgery and skin grafting. Secondary skin closure was done 20 days after admission.

Case 4
A 58-year-old female patient underwent a TVT (tension-free vaginal tape) procedure. Three years after procedure she was admitted with severe gluteal and elbow pain, and suppurative exudates from her vaginal area. Her evaluation was consistent with a diagnosis of necrotizing fasciitis and she was started on multiple antibiotics and taken to urgent surgery for exploration, TVT removal and debridement. At first, we started with alginate dressing changes every day, and on daily basis reevaluated surgical wounds for potential surgical revision. The exudate from treated wound was extensive (Figure5). After 10 days we started treatment with negative pressure with instillation (VAC Ulta) (Figure6). Instillation cycle with saline solution was performed every 6 hours. After 20 days, wounds were clean and granulation tissue was seen on wound bed (Figure7). We started with the gradual approximation of the edges of the wound with staples (Figure8). Skin defect was covered with split-thickness skin graft (Figure9) and fixed with polyvinyl alcohol dressing under NPWT for the next 6 days. Patient was dismissed from hospital after 70 days without neurological or motoric symptoms, although sciatic nerve was completely exposed in the wound bed.

Discussion
The In this case study, VAC treatment was found to be effective in managing different clinical problems in perineum and surrounding areas. VAC has been used with great success to care for a variety of wounds. VAC involves the application of foam to a wound, adding a seal of adhesive drape, and then applying sub-atmospheric pressure to the wound in a controlled way (11). Our patients were more comfortable with VAC treatment and VAC healed the wounds with fewer interventions than with conventional wound care. Level of comfort and also mobility of the patients was substantially increased, because the system is portable and patients are not confined to their beds. VAC patients could be bathed and there is no bad odour from the wound. Thus, a marked increase in quality of life was observed when VAC was used compared to conventional treatment. In addition, nurses and most physicians preferred it to conventional dressings because of the effectiveness of VAC treatment and time savings. This treatment was found to be similar in cost to conventional treatment. One of the adverse effects associated with VAC therapy is pain. With the use of VAC ULTA we can decrease discomfort with addition of local anaesthetics like Xylocaine in installation fluid before dressing change. However, the pain is more related to the nature of the wounds treated by VAC rather than to VAC itself. Several factors affect the healing of perineal wounds. In addition to ensuring appropriate debridement, adequate nutrition, urine, stool and gas passage and prevention of excessive pressure, the healing of wounds in the perineum present multiple challenges. Because of anatomic conditions it is difficult to secure dressing air tightly, risk of infection is higher because of faecal and urinary flow and immobilization of the patient is often necessary.
To get a seal around the wound or tubing is mandatory. Modelling drapes in smaller stripes and careful application on dry skin wiped with acetone helps in this situation. If additional sealant is needed to maintain a seal, the application of a stoma adhesive paste around drains and at leak sites is useful. Urinary catheter or cystostomy diverts urinary flow. Loop ileostomy on the right side is preferred when treatment is expected to be finished in one month and when wounds are extending to the left side of the body. Colostomy is preferred by authors when long treatment and extensive reconstruction procedures are anticipated or anal region is involved. In some cases, the use of temporary containment device that consists of a silicone catheter, syringe, and collection bag (Flexi-Seal FMS, Convatec, Princeton, NJ) is indicated. The main contraindication to this catheter is injured anus or rectum or very weak sphincter muscles, which may not be able to hold the device in place. Using this system, the stool should be also softened to prevent obstruction of catheter.

Conclusion
The use of VAC system has revolutionized wound healing. By increasing granulation and wound contraction, the VAC promotes earlier wound closure, skin grafting with improved graft adherence and therefore earlier discharge from the hospital. Its use in the perineum presents a challenge, but with proper application and use of modified techniques, it offers an important advance in the treatment of these debilitating and sometimes fatal wounds.