A prospective, randomized, controlled clinical study on the effectiveness of a single-use negative pressure wound therapy system, compared to traditional negative pressure wound therapy in the treatment of diabetic ulcers of the lower extremities

Advances in Chronic Wound Management: From Conventional Treatment to Novel Therapies and Biological Dressings

Chronic wounds can be classified as diabetic foot ulcers, pressure ulcers, or venous leg ulcers. Chronic wound management has become a threat to clinicians and constitutes a major healthcare burden. The healing process of chronic wounds requires many factors to work in concert to achieve optimal healing. Various treatment options, ranging from hypoxia to infection, have evolved considerably to address the challenges associated with chronic wound healing. The conventional and accelerating treatments for chronic wounds still represent an unmet medical need due to the complex pathophysiology of the chronic wound microenvironment. In clinical settings, traditional chronic wound care practices rely on nonspecific topical treatment, which can reduce pain and alleviate disease progression with varying levels of success but fail to completely cure the wounds. Conventional wound dressings, such as hydrocolloids, gauze, foams, and films, have also shown limited success for the treatment of chronic wounds and only act as a physical barrier and absorb wound exudates. Emerging advances in treatment approaches, including novel therapies (stem cells, microRNAs, and nanocarrier-based delivery systems) and multifunctional biological dressings, have been reported for chronic wound repair. This review summarizes the challenges offered by chronic wounds and discusses recent advancements in chronic wound treatment.

Negative-Pressure Wound Therapy: What We Know and What We Need to Know

Negative-pressure wound therapy (NPWT) promotes wound healing by applying negative pressure to the wound surface. A quarter of a century after its introduction, NPWT has been used in various clinical conditions, although molecular biological evidence is insufficient due to delay in basic research. Here, we have summarized the history of NPWT, its mechanism of action, what is currently known about it, and what is expected to be known in the future. Particularly, attention has shifted from the four main mechanisms of NPWT to the accompanying secondary effects, such as effects on various cells, bacteria, and surgical wounds. This chapter will help the reader to understand the current status and shortcomings of NPWT-related research, which could aid in the development of basic research and, eventually, clinical use with stronger scientific evidence.

Negative Pressure Wound Therapy Promotes Wound Healing by Inhibiting Inflammation in Diabetic Foot Wounds: A Role for NOD1 Receptor

Aims: Diabetic foot results in frequent amputation and quality-of-life reduction in diabetes population. These lesions are featured by a prolonged and exaggerated inflammation with a significant impairment in local bacterial invasion. Negative pressure wound therapy (NPWT) attenuates hyperinflammation in the healing of diabetic foot wounds, but the potential mechanism of NPWT down-regulated inflammatory reaction still remains elusive. This study aims to explore the inflammatory signaling involved in the effect of NPWT on diabetic ulcer. Methods: Thirty patients with diabetic foot ulceration were divided into NPWT group (treated with NPWT, n = 10), NPWT + FK565 group (treated with NPWT combined with FK565 which is NOD1 receptor ligand, n = 10) and control group (n = 10). After two weeks treatment, samples were harvested and analyzed by histochemistry for infiltration of inflammatory cells, immunofluorescence stain for NOD1, western blotting for NOD1, RIP2 (Receptor interacting protein 2), IL-1β, TAK1 (Transforming growth factor-β-activated kinase1), p65 and real time-PCR for expression of NOD1 and RIP2. Results: NPWT could notably accelerate the diabetic wound healing through alleviating inflammatory reaction. The immunofluorescence analysis results revealed that NOD1 was mainly expressed in the cytoplasm and noticeably decreased after the NPWT treatment. And NPWT obviously decreased both the mRNA and protein level of NOD1 and RIP2. Moreover, The protein expression of IL-1β, TAK1 and p65 in the NPWT-group were significant decreased. Conclusion: NPWT effectively promotes wound healing by suppressing the wound inflammation in diabetic foot, which is mediated at least in part by suppression of NOD1 receptor.

Effective negative pressure wound therapy for open wounds: The importance of consistent pressure delivery

Two distinct design concepts exist for single-use negative pressure wound therapy systems: Canister-based versus canisterless. The canister-based technology provides intrinsic stable delivery of the intended negative pressure, because exudate is constantly transferred from the wound into a canister, thereby preventing dressing saturation. In contrast, with a canisterless system, where delivery of the negative pressure depends on continuous evaporation of wound fluids from its dressing, loss of the intended wound-bed pressure may occur due to dressing saturation. To investigate whether these two designs differ in their mechanobiological effect with respect to magnitudes and distributions of tissue strain fields under the absorptive dressing, termed the influence zone, we integrated computational modelling with an animal study. This influence zone must be of biologically influential strain levels and extend sufficiently into the peri-wound for stimulating fibroblasts to migrate and progress the healing. We found that an effective influence zone requires continuous delivery of the intended pressure to the wound-bed. Loss of negative pressure at the wound-bed below 40 mmHg adversely lowered the peri-wound stimulation around a 120 × 70 mm sized wound to less than one-third of the baseline stimulation, and further pressure decreases to 20 mmHg or lower resulted in complete lack of peri-wound mechano-stimulation.