Triggering Drug Release and Thermal-Disrupting Interface Induced Mitigation of Composite Photothermal Hydrogel Treating Infectious Wounds

Introduction: With the development of photothermal technology, the appearance of composite photothermal hydrogels has increased the selectivity of treating infectious skin defects. However, how to design composite photothermal hydrogel with better antibacterial performance, reduce the resistance rate of bacteria, and the damage rate of normal tissue still needs further study.Methods: The Prussian blue and tannic acid were loaded on polyacrylamide hydrogels. Characterization of DLS, Zeta potential, UV absorption spectrum, hydrogel swelling rate, scanning electronic microscopic, drug release profile, photothermal properties, in vitro cytocompatibility, and antibacterial properties. Experiments were measured by skin defect repair, antibacterial detection, and histological staining experiments.Results: The polyacrylamide hydrogel with photothermal effect and controllable release of tannic acid was successfully prepared. The hydrogel has strong light transmittance and adhesion, and the swelling rate can reach 600%, which improves the self-cleaning ability. SEM results showed the porous structure of hydrogels, promoting cell growth. Through photothermal switches, the composite hydrogel represented adjustable and controllable drug release ability. Combined with the synergistic antibacterial effect of tannic acid, this further enhanced the antibacterial ability and reduced the probability of antibiotic resistance. The in vitro and in vivo experiments showed the hydrogel had good biocompatibility and excellent antibacterial properties, which could promote the repair of infectious skin defects in SD rats.Conclusion: We fabricated a hydrogel with a triggering drug release rate, alleviating heat damage, transparent morphology, mechanical stability, strong adhesion, good biocompatibility, and synergistic antibacterial ability, which presents new treatment options for infectious skin defect repair.

Microvascular skin coverage in wounds that expose the Achilles tendon

Achilles tendon rupture is one of the most frequent tendon ruptures. Surgical intervention is the best option, but it has a high rate of complications leading to skin infections and necrosis. Extensive and aggressive debridement is necessary, producing tendon exposure and large skin defects. There are many alternatives for the skin coverage of the Achilles tendon, like sequential closures, vacuum assisted closure, local flaps, regional flaps, and more recently and efficiently microsurgery flaps. Skin defects in the Achilles tendon region have many peculiarities in comparison with other parts of the body: it is a zone that is always under mechanical stress due to footwear, this is why it must be highly resistant but thin. Its coverage must have sensitive properties, endure tendon gliding and allow early rehabilitation. Sometimes tendon reinforcement or creation or a neo tendon will be needed. For fulfilling these requirements free flaps by microsurgery are the only option in 90% of the cases. In this review article, we analyze three of the most frequently used free flaps in reconstructive medicine for complex Achilles tendon defects; free radial forearm flap, free radial forearm flap with vascularized flexor carpi radialis tendon and free anterolateral thigh (ALT) flap with vascularized fascia lata. This choice will be determined by the number of tissues involved, size of the defect, etiology of the defect, overall condition of the affected extremity and quality of neighboring tissues.

The possibility of simultaneous combined skin grafting during the installation of synthetic implants after cranial trepanation

Introduction. Over the past 20 years, with an increase in the number of decompression trepanations in the Russian Federation and abroad, the number of cranioplasties performed has increased. Despite the development of technology, these surgical interventions are inevitably accompanied by a number of complications (up to 36 %), including the for‑ mation of skin defects. The choice of the optimal algorithm for the treatment of skin defects after cranioplasty remains the subject of debate.The purpose of the publication is to demonstrate by a clinical example the possibility of simultaneous combined skin grafting during the installation of synthetic implants after cranial trepanation, as well as to analyze the outcomes and com‑ plications of such operations.Materials and methods. For the period 2017–2019 under our supervision there were 42 patients after craniotomy, 32 of which were cranioplasty, and 10 plastic surgery of the defects of the scalp after removal of synthetic implants. In the course of the analysis, the structure and terms of surgical interventions, the length of hospitalization, the frequen‑ cy and structure of complications, as well as the timing of their development were studied.The article presents one of the cases of treatment and simultaneous installation of a titanium plate, combined skin grafting in a patient who has undergone previously decompressive craniotomy, cranioplasty with protacryl.Results. Simultaneous cranioplasty with skin grafting was performed in 3 out of 42 patients. The average hospitalization time after such an intervention was significantly less than with two‑stage plastic surgery (28.0 ± 3.9 and 52.0 ± 2.7 days, respectively, p <0.05). There were no complications in the postoperative period after a single‑stage plastic surgery, but after a two‑stage one, 2 cases of divergence of the wound edges and the formation of fistulas above the implants were registered.Conclusion. The data obtained illustrate that, given the technical feasibility, as well as the satisfactory condition of the skin flap, simultaneous cranioplasty with combined skin grafting can be one of the methods of choice in the treat‑ ment of extensive defects in the skin of the head and skull.

Features of plastics of skin flaws in the supporting surface of the foot

Plastics of skin defects of the foot as a reconstructive operation has a twofold purpose: on the one hand, as a means of preserving the organ, and on the other, as a means of restoring its supporting function.