Louis C. Argenta

Vacuum-assisted Closure: A New Method for Wound Control and Treatment: Clinical Experience

Despite numerous advances, chronic and other difficult-to-man-age wounds continue to be a treatment challenge. Presented is a new subatmospheric pressure technique: vacuum-assisted closure (The V.A.C.). The V.A.C. technique entails placing an open-cell foam dressing into the wound cavity and applying a controlled subatmospheric pressure (125 mmHg below ambient pressure). Three hundred wounds were treated: 175 chronic wounds, 94 subacute wounds, and 31 acute wounds. Two hundred ninety-six wounds responded favorably to subatmospheric pressure treatment, with an increased rate of granulation tissue formation. Wounds were treated until completely closed, were covered with a split-thickness skin graft, or a flap was rotated into the healthy, granulating wound bed. The technique removes chronic edema, leading to increased localized blood flow, and the applied forces result in the enhanced formation of granulation tissue. Vacuum-assisted closure is an extremely efficacious modality for treating chronic and difficult wounds.

Vacuum-assisted closure: a new method for wound control and treatment: animal studies and basic foundation.

A series of basic animal studies using a new subatmospheric pressure technique (The V.A.C.) to expedite wound healing are presented. The technique entails placing an open-cell foam into the wound, sealing the site with an adhesive drape, and applying subatmospheric pressure (125 mmHg below ambient) that is transmitted to the wound in a controlled manner. Utilizing a pig model, four studies were undertaken to determine the effect of subatmospheric pressure on laser Doppler-measured blood flow in the wound and adjacent tissue (N = 5), rate of granulation tissue formation (N = 10), clearance of bacteria from infected wounds (N = 5), and measurement of nutrient flow by random-pattern flap survival (N = 5). Blood flow levels increased fourfold when 125 mmHg subatmospheric pressure was applied. Significantly increased rates of granulation tissue formation (p ≤ 0.05) occurred with both continuous (63.3% ± 26.1%) and intermittent (103% ± 35.3%) application. Tissue bacterial counts significantly decreased (p ≤ 0.05) after 4 days of application. Random-pattern flap survival significantly increased (p ≤ 0.05) by 21% compared to controls. We determined that the application of controlled subatmospheric pressure creates an environment that promotes wound healing.

The use of vacuum-assisted closure therapy for the treatment of lower-extremity wounds with exposed bone

&NA; Lower‐extremity wounds with exposed tendon, bone, or orthopedic hardware present a difficult treatment challenge. In this series of patients, subatmospheric pressure therapy was applied to such lower‐extremity wounds. Seventy‐five patients with lower‐extremity wounds, most of which were the result of trauma, were selected for this study. Dressings made of sterile open‐cell foam with embedded fenestrated tubing were contoured to the wound size and placed into the wound. The site was covered with an adhesive plastic sheet. The sheet was placed beneath any external fixation devices, or the fixation device was enclosed within the sheet. The tubing was connected to the vacuum‐assisted closure pump. Continuous subatmospheric suction pressure (125 mmHg) was applied to the wound site. The wounds were inspected and the dressings were changed every 48 hours. Vacuum‐assisted closure therapy greatly reduced the amount of tissue edema, diminishing the circumference of the extremity and thus decreasing the surface area of the wound. Profuse granulation tissue formed rapidly, covering bone and hardware. The wounds were closed primarily and covered with split‐thickness skin grafts, or a regional flap was rotated into the granulating bed to fill the defect. Successful coverage was obtained without complication in 71 of 75 patients. Wounds have been stable from 6 months up to 6 years. (Plast. Reconstr. Surg. 108: 1184, 2001.)

Comparative study of survival of autologous adipose tissue taken and transplanted by different techniques.

In recent years, adipocytes obtained by suction-assisted lipectomy have been used for implantation by injection methods. This study is designed to assess the appearance of suctioned and excised adipose tissue and its survival after being injected or implanted into different tissues (0.5 cc into the rectus muscle and 0.5 cc into the dorsal ear skin) of New Zealand White rabbits. The results showed that significant numbers of adipocytes were ruptured after suction procedures. The intact cells represented approximately 10 percent of the fat cell population. Fat cells in aspirated and excised samples remained intact and did not differ histologically. After being injected into tissue, adipocytes appeared to survive better for a short term in a more vascularized bed (rectus muscle) than in a low vascular area (ear dermis). Long-term studies at 6− to 9-month intervals revealed transplanted adipose tissue, taken by suction or excision, being replaced with fibrosis, although cystic spaces and only a small number of surviving adipocytes were still present. Insulin did not show any protective effects on survival of the adipocytes during their transplantation.

Effects of varying levels of subatmospheric pressure on the rate of granulation tissue formation in experimental wounds in swine.

The use of subatmospheric pressure to promote wound healing has increased in popularity during the last several years. The original studies on granulation tissue formation used a 125-mmHg vacuum. The use of alternative sources of subatmospheric pressure has led to many questions regarding efficacy or risk. In this report a swine model is used to quantify and compare the effects of low vacuum suction (25 mmHg) and high vacuum suction (500 mmHg) produced by various vacuum pumps and wall suction systems with the standard 125-mmHg vacuum. Additionally, the effects of an unregulated air leak in the sealing system were examined. All four wound treatments were examined on each of 4 pigs. Wounds were treated until one of the wounds had granulated to a level flush with the surrounding tissue. Wounds treated with the standard 125-mmHg vacuum had filled with granulation tissue by day 8. At this time wounds treated with 25 mmHg had filled 21.2% with new granulation tissue, and wounds treated with 500 mmHg had filled 5.9% with new tissue. Wounds treated with 125 mmHg with a hole in the sealing drape had increased in size 197% because of the debridement of necrotic tissue. In conclusion, wounds treated with a 125-mmHg vacuum exhibited a significant (p < 0.0001) increase in the rate of granulation tissue formation compared with treatment at 25 mmHg or 500 mmHg. The presence of an unregulated air leak in the sealing drape results in significant progression (p < 0.0001) of the wound secondary to dehydration and progressive necrosis.

Vacuum-assisted closure: state of clinic art.

Summary: Treatment of wounds has been the cornerstone of plastic surgery since its inception. Vacuum-assisted closure provides a new paradigm that can be used in concert with a wide variety of standard existing plastic surgery techniques. It was originally developed as an alternative treatment for debilitated patients with chronic wounds. It has rapidly evolved into a widely accepted treatment of chronic and acute wounds, contaminated wounds, burns, envenomations, infiltrations, and wound complications from failed operations. The ease of technique and a high rate of success have encouraged its adaptation by thoracic, general, trauma, burn, orthopedic, urologic, as well as plastic surgeons. This article discusses multidisciplinary advances in the use of the vacuum-assisted closure technique over the past 10 years and its status as of 2006. Creative surgeons continue to regularly adapt the system to difficult problems. This technique in trained surgical hands greatly enhances the scope and safety of wound treatment.

An Increase in Infant Cranial Deformity with Supine Sleeping Position

Abnormalities of the occipital cranial suture in infancy can cause significant posterior cranial asymmetry, malposition of the ears, distortion of the cranial base, deformation of the forehead, and facial asymmetry. Over the past 2 years, we have noted a dramatic increase in the incidence of deformation of the occipital skull in our tertiary referral center. Our patient referral base has not changed appreciably over the past 5 years and patients have been referred from the same primary practitioner base. The timing of this increase correlates closely with the acceptance in our area of recommended changes in sleeping position to supine or side positioning for infants because of the fear of sudden infant death syndrome (SIDS). A total of 51 infants with occipital cranial deformity, with a mean age of 5.5 months at presentation, have been evaluated and treated by a single craniofacial surgeon in the 16-month period from September 1993 to December 1994. Older infants were treated with continuous positioning by the parent keeping the infant off the involved side. Younger infants and those with poor head control were treated with a soft-shell helmet. Mean timing of initial diagnosis and start of treatment was 5.5 months. Mean duration of helmet for positional treatment was 3.8 months. To date, only 3 of 51 patients have required surgical intervention, and other patients demonstrated spontaneous improvement of all measured parameters. Follow up has ranged from 8 to 24 months. We believe that most occipital plagiocephaly deformities are deformations rather than true cranio-synostoses. Despite varying amounts of suture abnormality evidenced on computed tomographic scans, most deformities can be corrected without surgery. In cases where progression of the cranial deformity occurs, despite conservative therapy, surgical intervention should be undertaken at approximately 1 year of age. The almost universal acceptance in the State of North Carolina of positioning neonates on their backs to avoid SIDS, may well increase the incidence of these deformities in the future.

The use of tissue expansion in head and neck reconstruction.

The use of expanding prostheses to augment local tissues in reconstruction of the head and neck has been successfully accomplished in 13 patients over the past three years. Excellent results and reliability have been demonstrated.

A controlled subatmospheric pressure dressing increases the rate of skin graft donor site reepithelialization

The ability to increase the rate of skin graft donor site reepithelialization significantly in a cost-effective manner has important implications for the patient undergoing major reconstructive procedures. In this study the effect of externally applied reduced pressure (the V.A.C.) on the rate of healing of donor site wounds was initially investigated using a porcine model (N = 4), then repeated on humans (N = 10). Spirt-thickness skin grafts were harvested from the backs of pigs using standard technique. Half of the donor sites were treated with subatmospheric pressure (125 mmHg) and half were treated with an OpSite dressing. Biopsies taken every 48 hours demonstrated that sites exposed to reduced pressure healed at a much faster rate than sites treated with a standard occlusive dressing. Similarly, donor sites in humans reepithelialized faster in 7 of 10 patients, the rate was. the same in 2 of 10 patients, and Opsite was faster in 1 of 10 patients. We believe this technology has the potential to be a relatively simple and cost-efficient method for increasing the rate of donor site healing.

Carcinoma of the Lung: Results of Treatment over Ten Years

Mediastinal lymph node dissection in conjunction with pulmonary resection was performed on 437 patients with bronchogenic carcinoma at the University of Michigan Medical Center from 1959 to 1969. The absolute five- and ten-year survival rates for patients undergoing curative resection were 36.2 and 14.4%, respectively. The five-year survival of those without nodal metastases was 49.3%, and it was 31.1% in patients with hilar metastases only. The five-year survival of patients with mediastinal metastases who received radiation therapy was 23.1%. Of the 193 patients with squamous cell carcinoma, 43% lived five years free from disease. The five-year survival of patients undergoing resection who had no hilar lymph node metastases was 53%, and it was 47.5% in those with hilar metastases only. The five-year survival in patients with mediastinal metastases who received postoperative irradiation was 34.4%.