Carceller Anna, González Torcal Juan Pedro, Viscor Ginés
Secció de Fisiologia, Departament de Biologia Cel⋅lular, Fisiologia i Immunologia, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain.
Front Physiol. 2020 Jun 19;11:695. doi: 10.3389/fphys.2020.00695. eCollection 2020.
Frostbite is a cold-related injury with a growing incidence among healthy subjects. Sequelae after frostbite are frequent and vary among individuals. Here, we studied the thermal response in the digits of hands and feet of five subjects who had recovered from previous frostbite, except for their lasting sequelae. We considered three different conditions: digits unaffected by frostbite nor sequelae (healthy), those affected but which did not suffer amputation (frostbitten without amputation), and the remainder/stumps of digits that underwent partial amputation (frostbitten with amputation). Three consecutive immersions in cold water (8°C; 3 min) interspersed by 1 minute of thermal recovery were performed. After 30 min, a topical 10% nifedipine preparation was applied to hands and feet, and the same cold exposure protocol to evaluate its effect was followed. In basal condition and immediately after each immersion, the temperature of individual digits was assessed using thermography. We observed different thermal responses among the different digits of hands and feet, even without the nifedipine treatment. Nifedipine had a cooling effect on healthy and post-amputated tissue without thermal stress. In cold conditions, topic nifedipine application improved the cold response in healthy fingers but had a negative effect on those from which parts had been amputated. The topical nifedipine had detrimental effects on toes in all conditions. Topical nifedipine can help to the preservation of healthy fingers exposed to cold, with adequate thermal insulation; but it is necessary to remark its potentially harmful effects on previously frostbitten tissue. Because of the differences observed on individual regional response to cold, thermography can be a useful tool in the frostbite prevention for subjects habitually exposed to cold environment.
冻伤是一种与寒冷相关的损伤，在健康人群中的发病率呈上升趋势。冻伤后的后遗症很常见，且因人而异。在此，我们研究了五名曾患冻伤且已康复但仍有持久后遗症的受试者手脚指的热反应情况。我们考虑了三种不同情况：未受冻伤及后遗症影响的手指（健康）、受冻伤但未截肢的手指（冻伤未截肢）以及接受部分截肢的手指残端（冻伤截肢）。进行了三次连续的冷水浸泡（8°C；3分钟），每次浸泡间隔1分钟的热恢复时间。30分钟后，在手脚上涂抹10%硝苯地平局部制剂，并遵循相同的冷暴露方案来评估其效果。在基础状态下以及每次浸泡后立即使用热成像技术评估各个手指的温度。我们观察到，即使在未使用硝苯地平治疗的情况下，手脚不同手指的热反应也有所不同。硝苯地平对无热应激的健康组织和截肢后的组织有降温作用。在寒冷条件下，局部应用硝苯地平可改善健康手指的冷反应，但对已截肢的手指有负面影响。在所有情况下，局部应用硝苯地平对脚趾都有有害影响。局部应用硝苯地平有助于在有足够保暖措施的情况下保护暴露于寒冷中的健康手指；但必须指出其对先前冻伤组织可能产生的有害影响。由于观察到个体对寒冷的局部反应存在差异，热成像技术可成为习惯性暴露于寒冷环境的受试者预防冻伤的有用工具。
