Kinetic Concepts Inc Research Articles

The Use of a Novel Canister-free Negative-Pressure Device in Chronic Wounds: A Retrospective Analysis.

Negative-pressure wound therapy (NPWT) is a mainstay in the treatment of acute and chronic wounds. Following the success of the Vacuum-Assisted Closure system (Kinetic Concepts Inc [KCI], an Acelity Company, San Antonio, Texas), many similar systems were developed with minor variations. However, these systems are best suited to wounds with soft-tissue defects. Moreover, the need for a canister to collect wound exudate adds to the size and weight of the device. A canister-free (CF) NPWT device was cleared by the FDA for the treatment of chronic wounds (Kalypto Medical, Mendota Heights, Minnesota). A retrospective study was designed to evaluate the effectiveness of the CF-NPWT device in promoting wound healing. The authors examined the records of 51 patients treated with the CF-NPWT device over a 21-month period. Study participants were treated in an outpatient setting, had at least 30 days of prior treatment, and carried insurance coverage through Medicare or Medicaid. The comparison of time to heal between groups was conducted using the log-rank, Breslow, and Tarone-Ware tests in conjunction with a Kaplan-Meier analysis. In the study population, 65% of the wounds achieved complete closure. For unhealed wounds, the mean wound area reduction was 31.9%, and the mean wound depth reduction was 57.5%. The mean time to heal was 56.9 days (95% confidence interval, 46.4-67.4 days). The results show that the CF-NPWT system meets or exceeds healing rates previously reported in the literature for canister-based systems. This CF device offers a more portable NPWT option, particularly effective in the treatment of shallow wounds.

Comparison of the effect of negative pressure wound therapy with and without installation of polyhexanide on the bacterial kinetic in chronic wounds

Abstract Background Negative pressure wound therapy (NPWT) has established successfully as a treatment option for acceleration of wound healing in a broad range of clinical indications. Systematic research investigating the bacterial kinetics on wounds is lacking and no studies are available comparing the microbiological difference of repeated instillation of polyhexanide (PHMB) against continuous NPWT without instillation of an antiseptic. The aim of this study was to investigate the bacterial bio-burden on wounds and to measure the bacterial kinetic during application of NPWT with and without intermitted instillation of 0.02% PHMB. Methods A cohort of 18 patients with chronic (n = 16) and acute (n = 2) wounds was treated either with NPWT alone or with additional intermitted instillation of 0.02% PHMB. Wound healing and bacterial load were assessed at every dressing change. All wounds were closed by split-thickness skin grafts or local Reverdin flaps. According to the manufacturer of the investigated NPWT system (V.A.C. therapy unit, Kinetic Concepts Inc. KCI) wounds were filled with a polyurethane sponge (pore size 0.4–0.6 mm) and occluded with a polyurethane foil (KCI Inc., USA). The NPWT-device was connected to the wound and operated at 100 mm Hg sub-atmospheric pressure utilizing an alternating pressure cycle of 5 min of suction followed by 2 min pause. The automated intermittent instillation lasted for 4–20 s, the exposure time was 20 min. After 60 min of NPWT, the instillation was started again. Results Seven split-thickness skin grafts, 3 Reverdin-flaps and one combined closure (Reverdin + split-thickness skin grafts) exhibited excellent wound healing after successful transplantation 4 weeks after intervention. The quality of wound granulation was excellent in all wounds, regardless of NPWT application with or without instillation of 0.02% PHMB. The bacterial spectrum remained mostly unchanged after treatment and had no influence on the outcome. Conclusion It was demonstrated that management of infected wounds with NPWT, with or without instillation of 0.02% PHMB, did not reduce the number of bacteria on wounds. Bacteria proliferate below a NPWT dressing and increase in numbers. Independently of bacterial kinetics, all wounds showed excellent granulation and healed with no complications. This observation challenges the concept that bacterial bioburden correlates with impaired wound healing.

Letter to the Editor: Negative Pressure Wound Therapy in Grade IIIB Tibial Fractures: Fewer Infections and Fewer Flap Procedures?

W e would like to support the interesting conclusions from a systematic review recently presented by Schlatterer and colleagues [1]. Their study addresses treatment for Grade IIIB tibial fractures and points to negative pressure wound therapy as an option that is changing the way many traumatologists think about the treatment of these difficult-to-manage wounds. As Schlatterer and colleagues point out, some clinicians support wound closure or stable muscle flap coverage within 72 hours to limit complications. The authors, however, found evidence to suggest that negative pressure wound therapy can be performed safely beyond 72 hours without increasing the risk of infection. These complex wounds can cause terrible morbidity and constitute a public health problem for many centers [2]. Through the years, researchers have devised a hierarchy of procedures within a hypothetical reconstructive ladder to guide the surgical treatment of wounds. This traditional reconstructive ladder, in its various iterations, subsequently has become a paradigm that helps to inform the choice of closure method across an array of defects. Currently, the increased availability of negative pressure wound therapy has illuminated its key benefits, including faster granulation tissue formation, less periwound edema, decreased closure time, less-frequent dressing changes, control of bacterial proliferation, and potential cost reduction. Although Janis et al. [3] have now incorporated negative pressure wound therapy as a new step in the traditional reconstructive ladder, we are advocating a different approach. In our experience, a descent in the usual reconstructive ladder (that is, from flaps to skin grafts or primary closure) is feasible if neoadjuvant negative pressure wound therapy is applied in the course of treating some complex wounds. This downscaled approach was taken in 106 patients with complex wounds seen between February 2011 and August 2014. All patients were initially subjected to negative pressure wound therapy via VAC system (Kinetic Concepts Inc, San Antonio, TX, USA). In 90 patients whose wounds were measured, the average wound area was 87 cm. (RE: Schlatterer DR, Hirschfeld AG, Webb LX. Negative pressure wound therapy in grade IIIB tibial fractures: Fewer infections and fewer flap procedures? Clin Orthop Relat Res. 2015;473:1802–1811). The authors certify that they, or any member of their immediate families, have no commercial associations (eg, consultancies, stock ownership, equity interest, patent/ licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research editors and board members are on file with the publication and can be viewed on request. The opinions expressed are those of the writers, and do not reflect the opinion or policy of CORR or The Association of Bone and Joint Surgeons. J. A. Farina Jr MD, PhD (&), C. E. F. de Almeida MD, PhD, E. G. S. C. Marques MD, J. L. G. Jorge MD, R. V. K. S. Lima MD Division of Plastic Surgery of Department of Surgery and Anatomy, Ribeirao Preto Medical School of University of Sao Paulo-Brazil, Av. Bandeirantes, 3900 Monte Alegre, Ribeirao Preto, Sao Paulo 14049-900, Brazil e-mail: jafarinajr@fmrp.usp.br Letter to the Editor Published online: 21 August 2015 The Association of Bone and Joint Surgeons1 2015

Epidermal micrografts produced via an automated and minimally invasive tool form at the dermal/epidermal junction and contain proliferative cells that secrete wound healing growth factors.

ABSTRACTOBJECTIVE:The aim of this scientific study was to assess epidermal micrografts for formation at the dermal-epidermal (DE) junction, cellular outgrowth, and growth factor secretion. Epidermal harvesting is an autologous option that removes only the superficial epidermal layer of the skin, considerably limiting donor site damage and scarring. Use of epidermal grafting in wound healing has been limited because of tedious, time-consuming, and inconsistent methodologies. Recently, a simplified, automated epidermal harvesting tool (CelluTome Epidermal Harvesting System; Kinetic Concepts Inc, San Antonio, Texas) that applies heat and suction concurrently to produce epidermal micrografts has become commercially available. The new technique of epidermal harvesting was shown to create viable micrografts with minimal patient discomfort and no donor-site scarring.DESIGN:This study was a prospective institutional review board–approved healthy human study.SETTING:This study was conducted at the multispecialty research facility, Clinical Trials of Texas, Inc, in San Antonio, Texas.PATIENTS:The participants were 15 healthy human volunteers.RESULTS:Epidermal micrografts formed at the DE junction, and migratory basal layer keratinocytes and melanocytes were proliferative in culture. Basement membrane–specific collagen type IV was also found to be present in the grafts, suggesting that the combination of heat and vacuum might cause partial delamination of the basement membrane. Viable basal cells actively secreted key growth factors important for modulating wound healing responses, including vascular endothelial growth factor, hepatocyte growth factor, granulocyte colony-stimulating factor, platelet-derived growth factor, and transforming growth factor α.CONCLUSIONS:Harvested epidermal micrografts retained their original keratinocyte structure, which is critical for potential re-epithelialization and repigmentation of a wound environment.

Use of a novel epidermal harvesting system in resource-poor countries.

The 2010 earthquake in Port-au-Prince, Haiti, highlighted the need for wound care in resource-poor countries. Subsequently, the University of Miami in Florida established one of the first interprofessional wound care centers located at Bernard Mevs Hospital in the central portion of Port-au-Prince, caring for patients with acute and chronic wounds. In 2012, the authors used a novel epidermal harvesting system (CelluTome Epidermal Harvesting System; Kinetic Concepts Inc, San Antonio, Texas) to harvest epithelium to be grafted on 7 patients at the Mevs Hospital with longstanding wounds. Epidermal microblisters were obtained from each patient's thigh using the CelluTome Epidermal Harvesting System. After 35 minutes, microblisters were raised using the device harvester, and an adhesive dressing was inserted into the harvester for transfer to the wound site. In patients with lower-extremity wounds, a 2-layer compression dressing was placed over epidermal grafts. Six of the 7 wounds improved or achieved complete closure in 4 weeks. One of the patients with a 2-year-old thigh wound failed to demonstrate improvement; this may have been secondary to an inability to adequately secure the graft. All donor sites healed without any visible scarring. The authors were able to conclude that epidermal grafting may represent a viable reconstructive option for patients in resource-poor countries.

Negative-pressure wound therapy for critically ill adults with open abdominal wounds

Open abdominal management with negative-pressure wound therapy (NPWT) is increasingly used for critically ill trauma and surgery patients. We sought to determine the comparative efficacy and safety of NPWT versus alternate temporary abdominal closure (TAC) techniques in critically ill adults with open abdominal wounds. We conducted a systematic review of published and unpublished comparative studies. We searched MEDLINE, PubMed, EMBASE, Scopus, Web of Science, the Cochrane Database, the Center for Reviews and Dissemination, clinical trials registries, and bibliographies of included articles. Two authors independently abstracted data on study design, methodological quality, patient characteristics, and outcomes. Among 2,715 citations identified, 2 randomized controlled trials and 9 cohort studies (3 prospective/6 retrospective) met inclusion criteria. Methodological quality of included prospective studies was moderate. One randomized controlled trial observed an improved fascial closure rate (relative risk [RR], 2.4; 95% confidence interval [CI], 1.0-5.3) and length of hospital stay after addition of retention sutured sequential fascial closure to the Kinetic Concepts Inc. (KCI) vacuum-assisted closure (VAC). Another reported a trend toward enhanced fascial closure using the KCI VAC versus Barker's vacuum pack (RR, 2.6; 95% CI, 0.95-7.1). A prospective cohort study observed improved mortality (RR, 0.48; 95% CI, 0.25-0.92) and fascial closure (RR, 1.5; 95% CI, 1.1-2.0) for patients who received the ABThera versus Barker's vacuum pack. Another noted a reduced arterial lactate, intra-abdominal pressure, and hospital stay for those fitted with the KCI VAC versus Bogotá bag. Most included retrospective studies exhibited low methodological quality and reported no mortality or fascial closure benefit for NPWT. Limited prospective comparative data suggests that NPWT versus alternate TAC techniques may be linked with improved outcomes. However, the clinical heterogeneity and quality of available studies preclude definitive conclusions regarding the preferential use of NPWT over alternate TAC techniques. Systematic review, level III.

Resection Arthroplasty, External Fixation, and Negative Pressure Dressing for First Metatarsophalangeal Joint Ulcers

A frequent complication for the diabetic patient is neuropathic ulceration on the plantar surface of the first metatarsophalangeal (MTP) joint which can be difficult to manage. Debridement and resection arthroplasty with temporary external fixation and VAC dressing (Kinetic Concepts Inc, San Antonio, TX) is an alternative operative treatment to amputation. This study examined the outcomes of one center's experience with patients who have undergone this procedure. This retrospective cohort study examined patients who underwent the procedure between March 2002 and March 2010. Information was obtained on relevant outcomes including: the initial procedure, secondary procedures on either foot, total time in external fixation, time until amputation, cause of ulceration and co-morbid conditions. During the study period, 16 patients underwent resection arthroplasty with external fixation for first MTP ulceration. Fourteen of these patients had underlying diabetes mellitus, one had Charcot-Marie-Tooth disease and one had neuropathy of unknown cause. All were available for followup at the end of the study period. Median followup was 38 (range, 3 to 96) months. At latest followup, six patients required amputation, either transmetatarsal or transtibial, to treat their recurring ulceration. Resection arthroplasty with temporary external fixation appears to be a safe, effective and possible alternative to amputation for the treatment of neuropathic ulceration of the first MTP.

Definition of efficiency in vacuum therapy – a randomised controlled trial comparing Redon drains with V.A.C.® Therapy™

Redon drains are still used to suction wounds for vacuum sealing. Vacuum-assisted closure (V.A.C.((R)); Kinetic Concepts Inc, San Antonio, TX) is a computer-controlled therapy system for delivering topical negative pressure therapy. The efficiency of V.A.C. in the treatment of pressure ulcers was prospectively studied in a randomised controlled trial in which patients with pressure ulcers were randomly assigned to negative pressure wound therapy (NPWT) using either V.A.C. or Redon bottles. The target parameters were absolute and relative proportion of wound area consists of granulation tissue, fibrin and necrosis. Other outcome measures were the number of dressing changes and time invested using each system. The study was terminated after a post hoc analysis after inclusion of ten patients because of the significantly better results when using V.A.C., and the substantially larger care effort needed in the Redon group compared with the V.A.C. group. An increase in surface granulation tissue of 54% was observed in the V.A.C. group, and a reduction in the Redon group (P = 0.001). The Redon group showed an increase in fibrin tissue at the wound base of 21.8%, whereas in the V.A.C group, a 27% reduction was observed (P = 0.035). Necrosis was reduced in the V.A.C. group, but this difference did not reach significance. Redon bottles are not a good alternative for V.A.C. therapy for delivering NPWT.

Wound Necrosis After Total Knee Arthroplasty

Quickly evolutive skin necrosis and deep infection after total knee arthroplasty (TKA) are not uncommon. Several predisposing factors, such as immunosuppression, malnutrition, steroid use, rheumatoid arthritis, multiple scars, and vascular disease can be involved in the onset of wound complications, as well as long tourniquet time and early knee flexion. Skin necrosis after TKA can be treated in different ways, including local wound care, debridement, and soft tissue coverage with muscle or skin grafts. This article presents a rare case of skin necrosis occurring in a patient without any other apparent risk factor after TKA. A 78-year-old woman affected by primary osteoarthritis of the right knee who had no comorbidities and who had already undergone TKA for primary osteoarthritis on the left knee underwent a cemented TKA. Three days postoperatively, she developed a fever and wound problems, which soon after turned into skin necrosis. This complication was first treated surgically with a debridement of the wound with antibiotic therapy and local wound care, then with vacuum-assisted closure (Kinetic Concepts Inc, San Antonio, Texas) therapy and soft tissue coverage using skin grafting. She had a complete recovery in the next 3 months; the skin grafting was well tolerated and the range of motion and functional outcome were good.

Delayed presentation of congenital diaphragmatic hernia manifesting as combined-type acute gastric volvulus: a case report and review of the literature

Acute gastric volvulus associated with congenital diaphragmatic hernia is an unusual surgical emergency. We describe a case of an 11-year-old girl who presented with a 4-day history of abdominal pain, nonproductive retching, cough, and shortness of breath. A chest radiograph revealed a large air-fluid level in left hemithorax and the presence of intestinal loops with marked mediastinal deviation. Nasogastric decompression was unsuccessful. Via a thoracoscopic approach, the large fluid-filled stomach was percutaneously decompressed but could not be reduced. Through a left subcostal incision, a left-sided diaphragmatic defect about 4 × 5 cm was encountered. A large portion of small intestines, ascending and transverse colon, strangulated but viable stomach, and a large spleen herniated through the defect. The contents were reduced, revealing a combined gastric volvulus. Once the diaphragmatic defect was repaired primarily, there was insufficient space in the abdominal cavity to contain all the viscera reduced form the chest. Therefore, we placed an AlloDerm patch on the fascia and closed with a wound V.A.C (Kinetic Concepts Inc, San Antonio, TX). Two weeks later, the wound was definitively closed; she recovered uneventfully and was discharged home 3 days later. To our knowledge, only 26 previous cases of acute gastric volvulus complicating a congenital diaphragmatic hernia in children have been reported in the literature. Our patient represents the 27th case and the first combined type acute gastric volvulus case.

Negative pressure wound therapy: potential publication bias caused by lack of access to unpublished study results data.

BackgroundNegative pressure wound therapy (NPWT) is widely applied, although the evidence base is weak. Previous reviews on medical interventions have shown that conclusions based on published data alone may no longer hold after consideration of unpublished data. The main objective of this study was to identify unpublished randomised controlled trials (RCTs) on NPWT within the framework of a systematic review.MethodsRCTs comparing NPWT with conventional wound therapy were identified using MEDLINE, EMBASE, CINAHL and The Cochrane Library. Every database was searched from inception to May 2005. The search was updated in December 2006. Reference lists of original articles and systematic reviews, as well as congress proceedings and online trial registers, were screened for clues to unpublished RCTs. Manufacturers of NPWT devices and authors of conference abstracts were contacted and asked to provide study information. Trials were considered nonrandomised if concealment of allocation to treatment groups was classified as "inadequate". The study status was classified as "completed", "discontinued", "ongoing" or "unclear". The publication status of completed or discontinued RCTs was classified as "published" if a full-text paper on final study results (completed trials) or interim results (discontinued trials) was available, and "unpublished" if this was not the case. The type of sponsorship was also noted for all trials.ResultsA total of 28 RCTs referring to at least 2755 planned or analysed patients met the inclusion criteria: 13 RCTs had been completed, 6 had been discontinued, 6 were ongoing, and the status of 3 RCTs was unclear. Full-text papers were available on 30% of patients in the 19 completed or discontinued RCTs (495 analysed patients in 10 published RCTs vs. 1154 planned patients in 9 unpublished RCTs). Most information about conference abstracts and unpublished study information referring to trials that were unpublished at the time these documents were generated was obtained from the manufacturer Kinetic Concepts Inc. (KCI) (19 RCTs), followed by The Cochrane Library (18) and a systematic review (15). We were able to obtain some information on the methods of unpublished RCTs, but results data were either not available or requests for results data were not answered; the results of unpublished RCTs could therefore not be considered in the review. One manufacturer, KCI, sponsored the majority of RCTs (19/28; 68%). The sponsorship of the remaining trials was unclear.ConclusionMulti-source comprehensive searches identify unpublished RCTs. However, lack of access to unpublished study results data raises doubts about the completeness of the evidence base on NPWT.

Vakuumversiegelung – Grundlagen, Indikationen, Kontraindikationen und Kostenbilanz

Vacuum therapy is an efficient alternative to conservative wound care and creates new possibilities for the treatment of a variety of chronic and acute wounds. Already more than two thousand years ago vacuum treatment was applied in traditional Chinese medicine and also today vacuum therapy is used more and more frequently in daily clinical practice. The positive effects of the therapy are based on the stimulation of blood flow, formation of granulation tissue, angiogenesis, as well as cell proliferation, accelerated secondary wound closure and the removal of bacteria from the wound. As can be demonstrated based on a clinical picture of the open abdomen, vacuum therapy based on KCI's (Kinetic Concepts Inc) VA.C. system (Vacuum Assisted Closure) provides a possibility for not only accelerating the healing process, but also significantly lowering mortality. Since vacuum therapy in the form of the V.A.C. system represents a relatively expensive intervention, a comparison with conventional healing methods is demonstrated. Clinical studies with high evidence level show that both economic and clinical advantages of the vacuum therapy speak for its application. Savings with respect to the faster healing rates, the reduced dressing changes, as well as hospital stay and the care requirements, and the reduction of subsequent illnesses, compensate for the higher initial costs. Although many reports exist on treatment successes with the application of V.A.C. therapy, there are several cases for which vacuum therapy is contraindicated. In order to make sure that V.A.C. therapy is effective, a range of precautions and contraindications are described. The European Wound management Association (EWMA) just wrote a position paper on V.A.C. therapy. This is available at www.ewma.org.

Scrotal and Penile Reconstruction Using the Vacuum-Assisted Closure Device

Fournier's gangrene is a necrotizing, soft tissue infection that spreads along the deep external fascial planes of the perineum, scrotum (or vagina), penis, thighs and lower abdomen. Due to the rapid progression of the disease, patients are frequently left with a large integumentary deficit. Treatment of the skin defect has been described in a multitude of ways including split-thickness skin grafting, burying the testes in the thighs, thigh flaps and a variety of myocutaneous and fasciocutaneous flaps. Many of the previously described techniques have worked well for smaller defects and for closure of wounds but fall short of aesthetic reconstruction of sexual organs. Described here is a technique using split-thickness skin grafts, with foam dressings as the bolster. This was performed using the vacuum-assisted closure device (Kinetic Concepts Inc, USA). This technique creates a natural appearing scrotum that holds the testes away from the body, in a physiological manner, and surfaces the penis with a natural appearance, in a functional manner. The technique results in nearly 100% graft take and greatly decreases length of hospital stay.