VAC Group Research Articles

Negative Pressure Wound Therapy Versus Conventional Dressing in Treatment of Diabetic Foot Wound

Background: Foot wounds in people with diabetes mellitus are a common and serious global health issue. Negative pressure wound therapy can be used to treat these wounds and a clear and current overview of current evidence is required to facilitate decision-making regarding its use. Aim of the Work: To compare the efficacy of negative pressure wound therapy with that of a control group using conventional moist wound dressings, in healing of diabetic foot ulcers, in terms of 1) Change in size of wound. 2) Rate of granulation tissue formation as percentage of ulcer surface area. 3) Period of hospital stay. 4) Cost of both modalities of treatment. And 5) Complications after treatment. Study Design: Prospective Randomized Controlled Trial. Place: This study was conducted in the vascular surgery department at Al-Azhar university hospitals. Methodology: The study included 50 patients randomized into two groups (25 patient for VAC therapy & 25 patient for conventional dressing) suffering from diabetic foot wounds. Results: In our study, 6 of 25 (24%) in the Conventional treatment group were females whereas 19 of 25 (76%) in the Conventional treatment group were males. 3 of 25 (12%) in the NPWT group were females and 22 of 25 (88%) were males. In the Conventional treatment group, 21 of 25 (84%) were above 60 years of age. 20 of 25 (80%) in the NPWT group were above 60 years of age. Wound bed showed signs of healing by granulation tissue formation in 19 among 25 patients (76%) compared to Conventional treatment, 7 showed granulation among 25 patients (28%) one week after initiation of treatment. (P=0.001). Granulation of the wounds was > 50% in 20 of the 25 patients underwent NPWT whereas only 3 of the 25 in the Conventional treatment had shown > 50% granulation. There was a highly statistically significant difference between average Granulation as % of ulcer area and it is significantly high in vacuum dressing. It was 51.92 ± 21.03 in Conventional treatment compared with 78.68 ± 18.12 in NPWT group (p- value < 0.05). Wound size was measured at initial presentation and then after treatment. Before treatment, the mean surface area of wounds in the NPWT group was 40.44 cm2, the Conventional treatment 38.52cm2. After wound management, mean surface area of the diabetic wounds was 36.08 ± 2.56 cm2 in the NPWT group and 37.63 ± 2.86 cm2 in the Conventional treatment. This represents a statistically significant difference (P=0.05). At the end of our study the incidence of secondary higher amputation in NPWT group was 5/25 (20%), the Conventional treatment 6/25 (24%). There was no significant difference between both groups (P=0.13). There is a statistically significant difference between average graft take-up and it is higher in vacuum dressing. It was 80.78 ± 14.54 in NPWT and 59.58±19.25 in control group. (P-value = 0.035). Daily mean cost in conventional dressing group was 67.43 ± 5.3 EP compared to 95.7 ± 10.2 EP in VAC group. A difference which is statistically different. Also, at the end of the study, total mean cost in conventional dressing group was 1976 ± 123 EP compared to 2275 ± 154 EP in VAC group. There was a difference in the total cost finally. Period of hospital stay till the wound was fully granulated and ready for skin grafting was 22.87 ± 7.62 in NPWT compared to 32.53 ± 10.17 in the conventional group. There is a highly statistically significant difference between average duration of hospital stay and it is reduced significantly in vacuum dressing. (p-value= 0.02). Conclusion: The rate of granulation tissue formation, wound surface area, overall graft survival was better in NPWT group as compared to conventional dressing group. Overall hospital stay and amputation rate were less in the NPWT group. Thus, NPWT can be considered as a superior option in the management of diabetic foot wounds. Cost of VAC therapy was higher than conventional dressing.

Outcome analysis of vacuum assisted closure application in open fractures of long bones

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; &lt;span lang="EN-IN"&gt;We performed a prospective analysis&lt;strong&gt; &lt;/strong&gt;to&lt;strong&gt; &lt;/strong&gt;compare the efficacy of the&lt;strong&gt; &lt;/strong&gt;vacuum assisted&lt;strong&gt; &lt;/strong&gt;closure (VAC therapy)&lt;strong&gt; &lt;/strong&gt;and conventional cotton&lt;strong&gt; &lt;/strong&gt;gauze&lt;strong&gt; &lt;/strong&gt;dressing of&lt;strong&gt; &lt;/strong&gt;wounds.&lt;/span&gt;&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; &lt;span lang="EN-IN"&gt;The study was conducted from July 2014 to&lt;strong&gt; &lt;/strong&gt;June 2016 on&lt;strong&gt; &lt;/strong&gt;patients admitted from&lt;strong&gt; &lt;/strong&gt;emergency department or presenting in the outpatient department of&lt;strong&gt; &lt;/strong&gt;the hospital. Necrotic tissues were debrided before applying VAC therapy. Dressings were changed every 3 or 4 days. For standard wound therapy, debridement followed by daily dressings was done. All patients&lt;strong&gt; &lt;/strong&gt;were&lt;strong&gt; &lt;/strong&gt;reconstructed with SSG/FLAP coverage after the granulation tissue was&lt;strong&gt; &lt;/strong&gt;sufficient. Two groups of 10 each compared prospectively. Data&lt;strong&gt; &lt;/strong&gt;were collected for&lt;strong&gt; &lt;/strong&gt;age, sex, time needed for sufficient granulation tissue for coverage, length of&lt;strong&gt; &lt;/strong&gt;hospital stay, no of debridements for VAC application and conventional gauze&lt;strong&gt; &lt;/strong&gt;dressings&lt;/span&gt;.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; &lt;span lang="EN-IN"&gt;Time needed&lt;strong&gt; &lt;/strong&gt;to have a good&lt;strong&gt; &lt;/strong&gt;granulation&lt;strong&gt; &lt;/strong&gt;tissue sufficient for coverage, length of&lt;strong&gt; &lt;/strong&gt;stay in&lt;strong&gt; &lt;/strong&gt;hospital, and&lt;strong&gt; &lt;/strong&gt;no&lt;strong&gt; &lt;/strong&gt;of&lt;strong&gt; &lt;/strong&gt;debridements&lt;strong&gt; &lt;/strong&gt;were&lt;strong&gt; &lt;/strong&gt;significantly&lt;strong&gt; &lt;/strong&gt;less in&lt;strong&gt; &lt;/strong&gt;VAC&lt;strong&gt; &lt;/strong&gt;group. No major&lt;strong&gt; &lt;/strong&gt;complication occurred that&lt;strong&gt; &lt;/strong&gt;was&lt;strong&gt; &lt;/strong&gt;directly&lt;strong&gt; &lt;/strong&gt;attributable to&lt;strong&gt; &lt;/strong&gt;treatment. &lt;/span&gt;&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; &lt;span lang="EN-IN"&gt;Vacuum assisted wound therapy was found to facilitate the rapid formation of healthy granulation tissue on open musculoskeletal&lt;strong&gt; &lt;/strong&gt;injuries, shortens&lt;strong&gt; &lt;/strong&gt;hospital stay and minimize secondary soft tissue defect coverage procedures.&lt;/span&gt;&lt;/p&gt;&lt;p&gt; &lt;/p&gt;

A randomized controlled trial comparing low cost vacuum assisted dressings and conventional dressing methods in the management of diabetic foot ulcers

Background: Diabetic foot ulcers are chronic wounds which are difficult to heal, due to ischemia and intrinsic defects in angiogenesis and impaired immunity against infection. VAC therapy influences positive mechanical forces on the growth of tissues, especially in stimulating cell migration and mitosis, optimizes blood flow, decreases local tissue edema from the wound bed and provides an occlusive environment for wound healing under moist, clean and sterile conditions. Aims and objective was to compare the effectiveness of low cost hospital made VAC dressing with conventional dressings in healing of diabetic foot ulcers.Methods: This study was a prospective, randomized controlled trial and included 60 patients with diabetic foot ulcers admitted over 3 months. Patients were randomly allocated to two groups: odd numbered patients to VAC therapy and the even numbered patients to conventional dressings. Wound swab was taken before the start of the study. The data was analyzed and presented in percentages or proportions using Chi-square test and Student-t-test wherever applicable. Results: In this study it was found that in the VAC dressing group 76.7% of the ulcers had red granulation tissue at the end of therapy compared to 46.7% in conventional group. The mean wound bed preparation time was found to be 15.60 days in the conventional dressing group and 8.50 days in the VAC therapy group. In the VAC group 72.73% ulcers had no bacteria at the end of therapy.Conclusion: In this study, it was found that Vacuum Assisted Closure therapy was more effective than conventional dressings in the wound bed preparation of diabetic foot ulcers.

Cost-effective Alternative for Negative-pressure Wound Therapy.

Background:Current predominantly used equipments for negative-pressure wound therapy (NPWT) are expensive. In current healthcare climate continually emphasizing cost containment, importance in developing more cost-effective alternatives cannot be understated. Previously, therapeutically equivalent methods of providing NPWT was demonstrated using just low-cost, universally available supplies, coined Gauze-SUCtion (GSUC). Here, we examine long-term potential financial savings of utilizing GSUC over commercialized products.Methods:A retrospective cost analysis was performed at the University of Chicago Medical Center between 1999 and 2014. All NPWT was provided via either GSUC or commercialized vacuum-assisted closure (VAC, KCI) device. Sum of all material component costs were reviewed to determine theoretical average daily cost. For the VAC group, recorded institutional spend to KCI was also reviewed to determine actual daily cost. In the GSUC group, this figure was extrapolated using similar ratios. Labor costs for each method were determined using analysis from prior study. Patient demographics, etiology, wound location, and treatment length were also reviewed.Results:Total of 35,871 days of NPWT was provided during the 15-year span. Theoretical average cost of VAC was $94.01/d versus $3.61/d for GSUC, whereas actual average was $111.18/d versus $4.26/d. Average labor cost was $20.11/dressing change versus $12.32. Combined, total cost of VAC therapy was estimated at $119,224 per every 1,000 days of therapy versus $9,188 for the GSUC.Conclusions:There is clear and significant cost savings from utilization of GSUC method of NPWT. Furthermore, the added advantage of being able to provide NPWT from universally accessible materials cannot be overstated.

A new low-cost negative-pressure wound therapy versus a commercially available therapy device widely used to treat complex traumatic injuries: a prospective, randomized, non-inferiority trial

OBJECTIVES:Negative-pressure wound therapy has been widely adopted to reduce the complexity of treating a broad range of acute and chronic wounds. However, its cost is high. The objective of this study was to evaluate the following two different methods of negative-pressure wound therapy in terms of healing time: a low-cost method of negative-pressure wound therapy (a pressure stabilizer device connected to a hospital wall-vacuum system with a gauze-sealed dressing, USP) and the standard of care (vacuum-assisted closure, VAC).METHODS:This is a randomized, controlled, non-inferiority, unblinded trial. Patients admitted with complex injuries to a trauma center in a public referral hospital who were indicated for orthopedic surgery were randomized to a USP or VAC group. The primary outcome was the time required to achieve a “ready for surgery condition”, which was defined as a wound bed with healthy granulation tissue and without necrosis or purulent secretion. Wound bed area contraction, granulation tissue growth and the direct costs of the dressings were secondary outcomes.RESULTS:Variation in area and granulation tissue growth were essentially the same between the systems, and healing time was equal between the groups (p=0.379). In both systems, serial debridement increased wound area (p=0.934), and granulation tissue was also increased (p=0.408). The mean treatment cost was US$ 15.15 in the USP group and US$ 872.59 in the VAC group.CONCLUSIONS:For treating complex traumatic injuries, USP was non-inferior to and less expensive than VAC.

Comparison of vonoprazan and proton pump inhibitors for eradication of Helicobacter pylori

Alternative eradication therapies for Helicobacter pylori infection are needed because of an increasing failure rate over the past decade. The aim of this study was to determine if vonoprazan, a new potassium-competitive acid blocker, showed superiority to existing proton pump inhibitors for primary eradication of H. pylori in routine clinical practice. Data for 573 patients who underwent primary H. pylori eradication therapy were retrospectively reviewed. Regimens included clarithromycin 200 mg, amoxicillin 750 mg, and an acid-suppressing drug [lansoprazole 30 mg (LAC), rabeprazole 10 mg (RAC), esomeprazole 20 mg (EAC), or vonoprazan 20 mg (VAC)] twice daily for 1 week. Eradication was successful in 73% (419/573) of patients using intention-to-treat (ITT) analysis and 76% (419/549) of patients in per-protocol (PP) analysis. The VAC group had a significantly superior eradication rate compared with the LAC and RAC groups in ITT (VAC 83%, LAC 66% and RAC 67%, p < 0.01) and PP analysis (VAC 85%, LAC 69% and RAC 70%, p < 0.01), and had a similarly high eradication rate to the EAC group (83% in ITT and 87% in PP). Although the eradication rate in the VAC and EAC groups was not significantly higher than in the LAC and RAC groups in patients with mild gastric atrophy with both ITT and PP analyses, it was significantly higher in patients with severe gastric atrophy (p < 0.01). The VAC group had a significantly higher H. pylori eradication rate than the LAC and RAC groups, and a > 80% eradication rate regardless of the degree of atrophy.

Intrathoracic Vacuum-Assisted Closure in the Treatment of Pleural Empyema and Lung Abscess

Complex pleural empyema or lung abscesses are either characterised by long-standing treatment (including treatment failure) or by a bad general condition of the patient (multiple morbidity, sepsis). The operative rectification is often associated with increased morbidity and mortality rates in these cases. Traditionally, the therapeutic tendency for such patients was towards primary creation of a thoracic window including open wound treatment, but this was always also associated with a long sickness and restrictions in the quality of life. The intrathoracic vacuum treatment (VAC) offers here entirely new options in the treatment of complicated pleural empyema and lung abscesses. We present an illustration of our own clinical experience associated with a selective literature research via Medline (keywords: VAC, vacuum-assisted closure, thoracic empyema). After the initial successes of the extrathoracic application of the VAC treatment, the procedure was also analysed for its intrathoracic/pleural use to treat pleural empyema and lung abscesses with and without bronchus stump insufficiency. Initially, the use of the intrathoracic VAC treatment was carried out via a thoracic window (with rib resection), later we developed a minimally invasive procedure (Mini-VAC) while relieving the osseous thorax. An additional intrapleural rinsing with antiseptics (Mini-VAC-Instill) is very practical in cases of proven germ populations. The benefits of the Mini-Vac/Mini-VAC-Instill are: immediate secretion suction with quick local cleaning, rapid germ eradication with a small risk of a fresh population, improvement of the expansion behaviour of the lung as well as short treatment times with quick reclosure of the thorax. In addition to many retrospective examinations, there has so far only been one cohort study in which the classic thoracic window was compared with the VAC treatment. The duration of the stomatic situation as well as the long-term survival in the VAC group were better here than those in the non-VAC group. The intrathoracic VAC treatment (Mini-Vac/Mini-VAC-Instill) is an innovative procedure that promotes wound cleaning and wound healing in complicated pleural empyema and lung abscesses. Due to the benefits of this procedure, including the improvement of the patient's comfort and the quality of life, the procedure has seen a rapid and broad clinical acceptance.

Vaccination of pigs with attenuated Lawsonia intracellularis induced acute phase protein responses and primed cell-mediated immunity without reduction in bacterial shedding after challenge

BackgroundLawsonia intracellularis causes porcine proliferative enteropathy and is one of the most economically important diseases in modern pig production worldwide. The Enterisol® Ileitis vaccine have been shown to reduce clinical disease and to increase weight gain, however, while the natural infection with L. intracellularis can provide complete protection against re-infection, this has not been achieved by this vaccine. We therefore undertook a detailed characterization of immune responses to L. intracellularis infection in vaccinated pigs (VAC) compared to previously infected pigs (RE) in order to pinpoint immunological determinants of protection. ResultsThe VAC pigs shed L. intracellularis to the same extent as non-vaccinated pigs after challenge, however less L. intracellularis in ileum and lymph nodes was seen post mortem. In the RE group, challenge did not lead to L. intracellularis shedding and no challenge bacteria were found post mortem. In both VAC and RE the acute phase haptoglobin response was diminished and L. intracellularis specific IgG responses were delayed and reduced compared to non-vaccinated pigs. On the other hand L. intracellularis specific IFN-γ responses tended to develop faster in the VAC group compared to controls. ConclusionAlthough vaccinated and non-vaccinated pigs shed L. intracellularis at similar levels after challenge, a lower number of intestinal L. intracellularis was observed in the vaccinated pigs at post mortem inspection. This might be due to the observed faster CMI responses upon challenge in vaccinated pigs. Complete protection against infection without L. intracellularis shedding, however, was only seen after a previous infection resulting in IFN-γ production predominantly by CD8+ and CD4+ CD8+ cells. Improved protective vaccines against L. intracellularis should therefore target stimulation of these T cell subsets.

Effects of oral deoxynivalenol exposure on immune-related parameters in lymphoid organs and serum of mice vaccinated with porcine parvovirus vaccine

Mice were exposed to deoxynivalenol (DON) via drinking water at a concentration of 2 mg/L for 36 days. On day 8 of treatment, inactivated porcine parvovirus vaccine (PPV) was injected intraperitoneally. The relative and absolute weight of the spleen was significantly decreased in the DON-treated group (DON). Antibody titers to parvovirus in serum were 47.9 ± 2.4 in the vaccination group (Vac), but 15.2 ± 6.5 in the group treated with DON and vaccine (DON + Vac). The IgA and IgG was not different in the DON, Vac an,d DON + Vac groups. IgM was significantly lower only in the DON + Vac group. However IgE was significantly increased in the Vac and DON + Vac group, but no change was observed between the Vac and DON + Vac groups. The concentrations of IL-2, IL-4, GM-CSF, MCP-1 and Rantes in serum, and IL-1α in mesenteric lymph node and MIP-1β in spleen were significantly increased by DON treatment compared to control. The concentrations of IL-2, IL-5, IL-6, IL-9, IL-12, IL-13 and Rantes in thymus, of IL-2 in spleen, and of IL-1α, IL-1β, IL-3, IL-5, IL-10, IL-17, G-CSF, GM-CSF and MCP-1 in mesenteric lymph nodes were significantly decreased in mice compared to those in the Vac group, while concentrations of IL-1α, IL-2, IL-9, IL-13,G-CSF, GM-CSF, IFN-γ, MCP-1, MIP-1α and TNF-α were significantly increased in serum compared to the Vac group. In conclusion, the results presented here indicate that exposure to DON at 2.0 mg/L via drinking water can disrupt the immune response in vaccinated mice by modulating cytokines and chemokines involved in their immune response to infectious disease.

Zearalenone Affects Immune-Related Parameters in Lymphoid Organs and Serum of Rats Vaccinated with Porcine Parvovirus Vaccine

Rats were administered zearalenone (ZEA) via gavage at dosages of 0, 1, 5, and 30 mg/kg for 36 days. On treatment day 8, inactivated porcine parvovirus vaccine (Vac) was injected intraperitoneally. Antibody production against porcine parvovirus was then measured as a function of ZEA treatment. Compared to the vaccine alone, ZEA treatment, with or without Vac, decreased the serum level of IgG. The level of IgM decreased in all ZEA groups at day 22, but the decrease was sustained only in the medium-dose ZEA group at day 36. The level of IgA was unchanged in the Vac only and ZEA groups at day 22, but was decreased in the 5 mg/kg ZEA plus Vac group compared to the Vac only group at day 36. The level of IgE was decreased by all doses of ZEA at day 22, but was unaffected in ZEA plus Vac groups compared to the Vac only group. The levels of IL-1 in the thymus and spleen; INF-γ in serum; IL-2, IL-6, and IL-10 in the thymus; and IL-10 and IFN-γ in the spleen decreased after ZEA administration. Furthermore, the levels of IL-1β in the spleen and mesenteric lymph node, IL-1β in the thymus, IL-2 in the thymus and spleen, IL-6 in the thymus, IL-10 and IFN-γ in the spleen, and GM-CSF and TNF-α in the thymus decreased after vaccination in rats exposed to ZEA. In conclusion, these results suggest that ZEA exposure via drinking water can cause an immunosuppressive effect by decreasing immunoglobulins in serum and cytokines in lymphoid organs.

Clinical outcome and microvascular blood flow in VAC®‐ and Sorbalgon®‐treated peri‐vascular infected wounds in the groin after vascular surgery – an early interim analysis

Vacuum-assisted wound closure (VAC(®)) therapy is considered to be superior to conventional dressings in the treatment of peri-vascular groin infections after vascular surgery at our department. Therefore, we performed an early interim analysis of the clinical outcomes in these seriously ill patients at risk of amputation and death. Patients were randomised to either VAC(®) (n = 5) or Sorbalgon(®) (n = 5; best alternative treatment) therapy after surgical debridement. Non-invasive, laser Doppler perfusion imaging (LDPI) studies of the skin adjacent to the undressed wound were performed after 14 days of wound treatment. There was no difference in LDPI values in VAC(®) versus Sorbalgon(®) treated patients (P = 0·46). One patient in the VAC(®) group suffered from two re-bleeding episodes, leading to vascular resection and transfemoral amputation and in the Sorbalgon(®) group two had a complete wound healing time of more than 4 months and one had a visible interposition bypass graft in the groin after 1 month of treatment. No patient died of the groin infection. Although not statistically proven, fewer wound treatment failures were recorded in the VAC(®) group, justifying this early interim analysis. LDPI studies were feasible.

Vacuum-Assisted Wound Closure is Superior to Primary Rewiring in Patients with Deep Sternal Wound Infection

Deep sternal wound infections are serious complications after cardiac surgery. The aim of the present study is to compare the outcome after vacuum-assisted wound closure to that after primary rewiring with disinfectant irrigation. The study additionally focuses on defining predictors for the failure of primary rewiring and its impact on postoperative outcome. Retrospective analysis was performed in 5232 patients who underwent cardiac surgery with a median sternotomy. 192 patients postoperatively developed deep sternal wound infections and were distributed into 2 therapy groups: a vacuum-assisted wound closure (= VAC) group and a primary rewiring (= RW) group, which was subdivided into healing after rewiring (= RW-h) and failure of rewiring (= RW-f). These groups were compared statistically to reveal coincidental pre-, intra- and postoperative parameters. Compared to the VAC group, the RW group showed a poorer outcome, although RW baseline characteristics were apparently beneficial. Primary rewiring failed in 45.8 % of all cases, which led to even worse outcomes. Important predictors for failure of primary rewiring were morbid obesity, diabetes mellitus type II, chronic obstructive pulmonary disease, preoperatively impaired left ventricular function, postoperatively positive blood and wound cultures, bilateral harvesting of internal thoracic arteries and the need for surgical reexploration. In spite of patients being in a worse condition, vacuum-assisted wound closure therapy resulted in improved outcomes and thus should be preferred to primary rewiring. Moreover we report on predictors which may indicate whether there is a high risk of rewiring failure.

Evaluating therapeutic effect in symptoms of moderate‐to‐severe premenstrual syndrome with Vitex agnus castus (BNO 1095) in Chinese women

To assess therapeutic effect of an extract of Vitex agnus castus (VAC, BNO 1095) in premenstrual syndrome (PMS) in Chinese women. It was a prospective, randomised, double-blind, placebo-controlled study carried out in China. Eligible patients were treated with VAC extract or placebo for three cycles. Symptoms were documented with PMS diary (PMSD), a daily rating scale with 17 items. Main efficacy variable was the reduction percentage of 17 symptom score documented in PMSD during the luteal phase of the third treatment cycle. A total of 67 patients were enrolled and randomly assigned to VAC group or placebo group. Of these, 64 patients completed the study (31 vs. 33). All the 17 symptoms showed a significantly greater improvement with VAC than placebo (P < 0.05) except lower abdominal cramping (P > 0.05). Vitex agnus castus is more effective than placebo in the treatment of moderate-to-severe PMS in Chinese women, especially in symptoms of negative effect and insomnia.

Evaluation of the adjuvant activity of naloxone, an opioid receptor antagonist, in combination with heat-killed Listeria monocytogenes vaccine

We have previously demonstrated the adjuvant activity of naloxone (NLX), a general opioid antagonist, using a DNA vaccine for herpes simplex virus type 1. Here, the adjuvant activity of NLX has been evaluated using a heat-killed Listeria monocytogenes (HKLM) vaccine as a model for general immunization against intracellular bacteria. BALB/c mice were divided into three groups: the Vac group received the HKLM vaccine alone; the NLX–Vac group received the HKLM vaccine in combination with the adjuvant NLX; and the control group received phosphate buffered saline (PBS). Our results indicate that the administration of NLX as an adjuvant enhances the ability of the HKLM vaccine to increase lymphocyte proliferation, delayed type hypersensitivity, and skewing of the immune response toward a T-helper 1 (Th1) pattern. Additionally, combination of NLX with the HKLM vaccine improves protective immunity against L. monocytogenes. In conclusion, administration of NLX as an adjuvant for the HKLM vaccine can enhance cell-mediated immunity and shift the immune response to Th1.

PR16 A PROSPECTIVE BLINDED RANDOMIZED CONTROLLED TRIAL OF COMMERCIAL VACUUM DRESSINGS VERSUS NON‐MECHANICAL TOPICAL NEGATIVE PRESSURE DRESSING FOR DAY SURGERY LOWER LEG SPLIT THICKNESS SKIN GRAFTS

Purpose: To show that ambulatory non‐mechanical negative pressure dressing results in equivalent graft take and survival compared with commercially available mechanical vacuum dressings.Methodology: Twenty‐four patients, both males and female, between 18 and 95 years of age in the Australian population requiring skin grafting of the lower limb from July 2008 were randomized consecutively into commercial vacuum assisted ambulatory dressing group, KCI Freedom VAC, [VAC] and non‐mechanical topical negative pressure dressing group using 14 gauge drain [Belovac]. Patients were discharged on the same day of surgery and reviewed at 5 or 6 days post‐operatively. Both groups were treated equally in all other facets of care. The dressings remained intact until outpatient review. A photo of the graft was taken upon removal of the dressing. Graft take/survival was measured from these photographs by an experienced plastic surgeon blinded to treatment group.Results: Graft take was found to be equivalent in both groups. All twelve patients in the VAC group were judged to have &gt;95% graft take at five/six days post‐op. In the Belovac group all twelve were judged to have &gt;95% graft take at 5/6 days. The cost for VAC group was $AUD413.50/478.50 [5/6 days] compared to $AUD55.93 for the Belovac dressing group.Conclusion: We conclude that non‐mechanical topical negative pressure dressings are equally effective as commercially available VAC dressings in for the treatment of lower limb skin grafts. We recommend that non‐mechanical topical negative pressure dressing is an acceptable, cheap and safe alternative to commercially available dressings for day surgery patient.

Reduced Serologic Response to Avian Influenza Vaccine in Specific-Pathogen-Free Chicks Inoculated with Cryptosporidium baileyi

Immunosuppression in chickens as a consequence of Cryptosporidium baileyi infection may compromise the effectiveness of vaccination for control of avian influenza (AI) H5N1. In a 13-wk study using 260 specific-pathogen-free chicks, immunological response and bursa weight:body weight ratios following vaccination against AI strain H5N1 were compared between uninfected and C baileyi-infected birds. The four experimental treatments were the following: infection with C. baileyi (5 x 10(5) oocysts dosed orally on day 0); C baileyi infection + vaccination against H5N1 (0.3 ml inactivated vaccine administered subcutaneously on day 7 and day 21; CB+VAC); vaccination only (VAC); and sham infection/vaccinations using sterile distilled water (control). At weekly intervals serum samples were analyzed by hemagglutination inhibition assay (HI), and five chicks/group were euthanatized for determination of bursa weights. In all but week 8, proportional bursa weights (bursa weight/body weight) were lower for CB+VAC chicks than for VAC chicks (i.e., the bursa index was below 1.0; average 0.81). Throughout the 13 wk, HI titres were lower (P < 0.01) in CB+VAC than in the VAC group, and compared with VAC, chicks in CB+VAC had a slightly shorter period of negative seroconversion. These data indicate bursal atrophy and immunosuppressive effects of C. baileyi infection on day-old chicks vaccinated against AI strain H5N1 and suggest that C. baileyi infection in chicks may increase the host susceptibility to AI virus.

Hepatitis B virus vaccine in lymphoproliferative disorders: a prospective randomized study evaluating the efficacy of granulocyte‐macrophage colony stimulating factor as a vaccine adjuvant

Hepatitis B virus (HBV) infection is effectively preventable by immunization with the commercially available recombinant HBV vaccines (HBV(vac)) in approximately 95% of healthy people. Immunosuppressive diseases like hematological malignancies are a risk factor for non-response to HBV(vac). The aim of this study was to determine the efficacy and safety of granulocyte-macrophage colony-stimulating factor (GM-CSF) as a vaccine adjuvant in lymphoproliferative disorders (LPD). One- hundred and two patients with LPD were randomized to receive either a single dose of 40 mug HBV(vac) intramuscularly or one course of 40 mug HBV(vac) after 5 mug/kg recombinant GM-CSF injection. Of the 94 patients that could be evaluated at 1 month, the seroprotection rate was higher in GM-CSF + HBV(vac) group (25.5% in GM-CSF + HBV(vac) group vs. 17% in HBV(vac) group). The median anti-HBs titer was also higher in GM-CSF + HBV(vac) group. However the difference did not reach to a significant level in terms of response rate and median antibody titers (P > 0.05). Univariate analysis identified age and time to vaccination from the last chemotherapy course as significant predictors of seroprotection. In multivariate analysis, age was the only predictor of achieving a seroprotective response. Patients who lost the seroprotective response during monitoring were boosted with a 20 microg HBV(vac) and they all achieved a seroprotective anti-HBs titer > 100 mIU/mL. In LPD, the response to HBV(vac) is impaired. GM-CSF enhance to HBV(vac) in terms of the rate of response and average of antibody titers at the dose and schedule given.

Negative Pressure Wound Therapy to Treat Hematomas and Surgical Incisions Following High-Energy Trauma

To evaluate the use of negative pressure wound therapy (NPWT) to augment healing of surgical incisions and hematomas after high-energy trauma. This study is a prospective randomized evaluation of NPWT in trauma patients, randomizing patients with draining hematomas to either a pressure dressing (group A) or a VAC (group B). Additionally, patients with calcaneus, pilon, and high-energy tibial plateau fractures were randomized to either a standard postoperative dressing or a VAC over the sutures. There were 44 patients randomized into the hematoma study. Group A drained a mean of 3.1 days, compared with only 1.6 days for group B. This difference was significant (p=0.03). The infection rate for group A was 16%, compared with 8% in group B. An additional 44 patients have been randomized into the fracture study. Again, a significant difference (p=0.02) was present when comparing drainage in group A (4.8 days) and group B (1.8 days). No significant difference was present at current enrollment for infection or wound breakdown. NPWT has been used on many complex traumatic wounds. Potential mechanisms of action include angiogenesis, increased blood flow, and decreased interstitial fluid. This ongoing randomized study has demonstrated decreased drainage and improved wound healing following both hematomas and severe fractures.

Immunologic responses of domestic and bighorn sheep to a multivalent Pasteurella haemolytica vaccine.

The efficacy of a Pasteurella haemolytica vaccine (serotypes A1, A2, and T10) to induce humoral antibodies and alter colonization of the upper respiratory tract by related P. haemolytica spp. strains was evaluated in 10 bighorn (Ovis canadensis canadensis) and 10 domestic (Ovis aries) sheep. Sheep of each species were divided into five pairs based on age and history of respiratory disease. One sheep in each pair was vaccinated twice 2 wk apart with 2 ml of vaccine (VAC group) and the remaining animals (NV group) were injected with 2 ml of sterile saline. Mild, transient lameness was the only observed adverse effect. Blood sera from the sheep were tested for agglutinating antibodies against whole cells of A1, A2, and T10 and for leukotoxin neutralizing antibodies. Antibody titers were expressed as the reciprocal log2 of the highest reactive dilutions. Domestic sheep > 1-yr-old and two bighorn sheep with a history of A1 infection had higher titers throughout the study against A1 cells than domestic sheep < 1-yr-old and bighorns without a history of A1 infection. Both domestic and bighorn sheep had log2 titers of 8 to 12 against A2 cells and 6 to 12 against T10 cells during this time. Bighorn sheep in the VAC group had 2 to 32 fold titer increases for A1 cells by 2 wk post-vaccination (PV) compared to 0 to 2 fold increases in VAC domestic sheep. Two to 16 and 0 to 8 fold increases in antibodies titers to A2 and T10 cells, respectively, were detected in sera of both VAC groups. Sera of bighorn sheep with a history of respiratory disease and all domestic sheep had log2 leukotoxin neutralizing antibody titers of 4 to 14 in contrast to < or = 2 in sera of bighorn sheep without a history of respiratory disease. Neutralizing antibody titers of two bighorns without a history of respiratory disease in the VAC group increased from log2 0 to 5 in one and from 0 to 9 in the other 2 wk PV. Antibody increases in these animals were no longer evident at 16 wk PV while titers of animals with histories of disease remained relatively stable. The types and numbers of Pasteurella spp. isolated from nasal and pharyngeal swabs varied throughout the study without conclusive evidence of suppression of colonization. Although the animals were not experimentally challenged to determine the efficacy of the vaccine, one VAC and one NV bighorn sheep died following introduction of an A2 P. haemolytica strain when leukotoxin neutralizing antibodies had returned to pre-vaccination levels. This vaccine appeared to be safe for use in bighorn sheep and stimulated moderate but transient increases in antibody levels which should provide some protection against naturally occurring disease. A vaccine which would induce production of high and maintained antibodies against multiple strains of P. haemolytica would be valuable for use in bighorn sheep maintained in captivity or when captured for relocation.