Frostbite: prevention and initial management.
ABSTRACT Abstract Zafren, Ken. Frostbite: Prevention and initial management. High Alt. Med. Biol. 14:9-12, 2013.-Frostbite is a local freezing injury that can cause tissue loss. Historically, it has been a disease of wars, but it is a hazard for anyone who ventures outdoors in cold weather. Frozen tissue is damaged both during freezing and rewarming. Frozen tissue is numb. Rewarming causes hyperemia and is often painful. Blisters and edema develop after rewarming. Hard eschar may form with healthy tissue deep to the eschar. Frostbite can be classified as superficial, without permanent tissue loss, or deep, with varying degrees of permanent tissue loss, often less than appearances suggest. It can be difficult to predict the amount of tissue loss at the time of presentation and early in the subsequent course. Prevention is better than treatment. It may be advisable not to rewarm frozen extremities in the field, but spontaneous thawing is often unavoidable. Extremities that have thawed should be protected from refreezing at all costs. Once in a protected environment, extremities that are still frozen should be rapidly thawed in warm water. Therapy with aspirin or ibuprofen may be helpful, but evidence is limited. Thrombolytic treatment within the first 24 hours after rewarming seems to be beneficial in some cases of severe frostbite. Prostacyclin therapy is very promising.
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ABSTRACT: A standardized reproducible animal model is desirable to gain a better understanding in the pathophysiology of frostbite injury and to develop novel therapies. Little has been studied about frostbite injury models. The depth and extent were not always being controllable and consistent. Therefore, we developed a frostbite injury model using the Göttingen Minipigs. 42 frostbite injuries were inflicted on the abdomen of seven minipigs using an aluminium bar (300g, circular with a radius of 1cm) frozen with liquid nitrogen to -196°C. The bar was applied for 1, 3, 6, 12, 30 and 60s. Five hours after injury biopsies were performed and evaluated by the presence of denatured collagen, blood vessels, follicular epithelial cells and mesenchymal cells. A large spectrum of frostbite injuries was obtained ranging from superficial, superficial partial, deep partial to full thickness. The depth of injury in the sets of frostbites was highly consistent (Pearson correlation ranged from r=0.89 to 0.94). We described a simple, inexpensive and safe swine frostbite model. The accurate reproducibility of the depth of the frostbite injuries allows researchers to accurately plan frostbite studies.Burns: journal of the International Society for Burn Injuries 07/2013; · 1.95 Impact Factor
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ABSTRACT: Abstract Objective: The purpose of this study was to formulate stable Ganoderma lucidum (GLT) nanogels suitable for topical delivery with a view to improve the therapeutic effect for frostbite. Methods: GLT nanosuspensions were formulated using the high-pressure homogenization technique and then suitably gelled for characterized. In order to confirm the advantages of GLT nanogel for dermal application, skin permeation studies in vitro and pharmacodynamic evaluation in vivo were studied and compared with GLT-carbopol gel. Results: The particle size analysis and SEM studies revealed that GLT nanosuspensions were still stably kept their particle size after suitably gelled by carbopol preparation. The drug content, pH, and spreadability of the GLT nanogel was found to be 99.23 ± 1.8%, 6.07 ± 0.1, and 26.42 (g·cm)/s, which were within acceptable limits. In vitro permeation studies through rat skin indicated that the amount of GLT permeated through skin of GLT nanogel after 24 h was higher than GLT-carbopol gel, and GLT nanogel increased the accumulative amount of GLT in epidermis five times than GLT-carbopol gel. No oedema and erythema were observed after administration of GLT nanogel on the rabbits' skin. Pharmacodynamic study showed that GLT nanogel was more effective than GLT-carbopol gel in treatment of frostbite. Conclusion: The GLT nanogel possess superior therapeutic effect for frostbite compared with the GLT-carbopol gel, which indicates that nanogels are eligible for the use as a suitable nanomedicine for dermal delivery of poorly soluble drugs such as GLT.Drug Delivery 06/2014; · 2.20 Impact Factor