Le Surgicel® à l’origine d’une nécrose cutanée dans un lifting cervicofacial : un cas clinique

A new hemostatic agent composed of Zn2+-enriched Ca2+ alginate activates vascular endothelial cells in vitro and promotes tissue repair in vivo

To control capillary bleeding, surgeons may use absorbable hemostatic agents, such as Surgicel® and TachoSil®. Due to their slow resorption, their persistence in situ can have a negative impact on tissue repair in the resected organ. To avoid complications and obtain a hemostatic agent that promotes tissue repair, a zinc-supplemented calcium alginate compress was developed: HEMO-IONIC®. This compress is non-absorbable and is therefore removed once hemostasis has been achieved. After demonstrating the hemostatic efficacy and stability of the blood clot obtained with HEMO-IONIC, the impact of Surgicel, TachoSil, and HEMO-IONIC on cell activation and tissue repair were compared (i) in vitro on endothelial cells, which are essential to tissue repair, and (ii) in vivo in a mouse skin excision model. In vitro, only HEMO-IONIC maintained the phenotypic and functional properties of endothelial cells and induced their migration. In comparison, Surgicel was found to be highly cytotoxic, and TachoSil inhibited endothelial cell migration. In vivo, only HEMO-IONIC increased angiogenesis, the recruitment of cells essential to tissue repair (macrophages, fibroblasts, and epithelial cells), and accelerated maturation of the extracellular matrix. These results demonstrate that a zinc-supplemented calcium alginate, HEMO-IONIC, applied for 10 min at the end of surgery and then removed has a long-term positive effect on all phases of tissue repair.

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A new Zn2+ enriched Ca2+ alginate hemostatic agent, HEMO-IONIC, has been developed.

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Non-absorbable, it achieves hemostasis with no foreign bodies left in the wound.

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HEMO-IONIC stimulates endothelial cell migration in vitro and angiogenesis in vivo.

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HEMO-IONIC, removed 10 min after application, promotes all stages of tissue repair.

Biomimetic hydroxyapate/polydopamine composites with good biocompatibility and efficiency for uncontrolled bleeding

Uncontrolled bleeding is thought to be the most deadly cause of pre-hospital, traffic, and military accidents death. However, the popular commercial hemostats can only realize the hemostasis of mild bleeding. Therefore, we developed polydopamine (PDA) composite materials (PMs), which applied hydroxyapatite as the parent body. The PMs were produced via lyophilization and functionalized with amino, phenol hydroxyls groups, which endowed hydrophobicity to materials. This ensured a high aggregation ability of blood cells to the PMs and they were tested to be as high as 300% compared with the negative control group. The clotting time was shortened to 79.7% compared with the usually used commercial hemostat (Celox) in the test of in vitro hemostasis. Through the results of PT and APTT tests, blood coagulation index test, and the analysis of intracellular Ca²⁺ activation, we further understood the mechanism of the hemostasis of the materials, which explained the low blood loss and quick coagulation time of the PM hemostats in detail. Besides, the low hemolysis and cytotoxicity of the PMs suggested the good biocompatibility of the hemostats, which was further proved by the regular morphology maintained by erythrocytes in the hemolysis tests. The study of nanoscale composites led the research for the methods of hemostasis.

Use of oxidized regenerated cellulose to stop bleeding after a facelift procedure

A 52-year-old woman came to our department about correcting a severe soft-tissue laxity after a weight loss of 67 kg. We performed a deep-plane face lift under sedation with local anesthesia. Three hours after the operation the patient had significant and diffuse bleeding, which was controlled by a local hemostatic agent made of oxidized regenerated cellulose (Tabotamp). In the weeks after the operation no local pain or skin damage was observed. We believe that oxidized regenerated cellulose could be a good ancillary therapy for controlling local bleeding associated with this kind of surgery.

Allergic contact dermatitis to regenerated oxidized cellulose contained in a matrix employed for wound therapy

We describe a case of a 40-year-old non-atopic woman with recurrent leg ulcers because of the factor V Leiden mutation who developed a severe eczematous lesions of the skin surrounding an ulcer of the right leg after the use of a protease-modulating matrix (Promogran, Johnson and Johnson, Gargrave, Skipton, UK). The patient was patch tested with the SIDAPA (Italian Society of Allergological, Occupational and Environmental Dermatology) standard series, a piece of the device as is, of the bovine collagen (Zyderm, Collagen Corporation, Palo Alto, CA, USA) as is, a piece of the gauze containing only regenerated oxidized cellulose (Tabotamp, Johnson and Johnson, Gargrave, North Yorkshire, UK) and of a fold towels in pure cellulose (Foscart, Bassano del Grappa, Italy). Patch tests gave a positive reactions to nickel sulphate and Promogran as is. We showed that the sensitizing agent was regenerated oxidized cellulose, a substance the treatment of ulcers and as is in and in combination with collagen in surgery for intraoperative hemostasis. The case reported suggests that regenerated oxidized cellulose can cause allergic contact dermatitis.