McCord Darlene E, Newton Barry E, Fore Jane, Chiffoleau Gwenael
McCord Research, Iowa City, IA, USA.
Adv Skin Wound Care. 2008 Feb;21(2):79-84. doi: 10.1097/01.ASW.0000305409.20232.af.
Current protocols call for stopping adjunctive skin care treatments during hyperbaric oxygen therapy (HBOT) because the hyperbaric environment is considered unsafe for skin care products. The elevated oxygen fraction and the increased pressure in the hyperbaric chamber dramatically increase the flammability potential of materials, leading to the need for rigorous standards to prevent flame ignition. A scientific method of evaluating the flammability risks associated with skin care products would be helpful. Several skin care products were tested, using established industrial techniques for determining flammability potential with some modification. The information obtained from these tests can help clinicians make more rational decisions about which topical products can be used safely on patients undergoing HBOT.
Wendell Hull & Associates conducted independent studies, comparing the oxygen compatibility for leading skin care products. Oxygen compatibility was determined using autogenous ignition temperature (AIT), oxygen index (OI), and heat of combustion (HoC) testing. AIT, a relative indication of a material's propensity for ignition, is the minimum temperature needed to cause a sample to self-ignite at a given pressure and oxygen concentration. OI, a relative indication of a material's flammability, is the minimum oxygen percentage that, when mixed with nitrogen, will sustain burning. HoC is the absolute value of a material's energy release when burning, if ignition occurs. Products with a high AIT, a high OI, and a low HoC are more compatible in an oxygen-enriched atmosphere (OEA). An acceptability index (AI) based on these 3 factors was calculated for the products, so the testers could rank overall material compatibility in OEAs (Lapin A. Oxygen Compatibility of Materials. International Institute of Refrigeration Commission Meeting; Brighton, England; 1973).
Test results for the skin products varied widely. The AIT, OI, HoC, and AI were determined for each product under described circumstances. The AIT results indicate that all products in 99.5% oxygen concentration under pressure will ignite and that a pattern based on the absence or presence of petroleum-based ingredients does not seem to exist. Products containing petrolatum, mineral oil, paraffin, and paraffin wax had a HoC that equaled or exceeded the HoC of gasoline, whereas products without petroleum-based ingredients had a significantly lower HoC. The OI of skin products not containing petrolateum-based ingredients was significantly higher than the OI of products containing it. The AI values the OI as the most important value: the higher the AI, the more acceptable the product is for use with oxygen. The silicone-containing, petroleum-free products received an AI up to 25 times higher than the petrolatum-based products. These findings suggest a wide variation in the safety profiles of skin products. Skin products being considered for use in an OEA should be screened for flammability risks. This screening will allow informed decisions about the fire safety of the products. Further research is indicated.
当前的方案要求在高压氧治疗（HBOT）期间停止辅助性皮肤护理治疗，因为高压环境被认为对护肤品不安全。高压舱内升高的氧含量和增加的压力显著增加了材料的可燃性，因此需要严格的标准来防止起火。一种评估与护肤品相关的可燃性风险的科学方法将有所帮助。使用经过一些修改的既定工业技术对几种护肤品进行了测试。从这些测试中获得的信息可以帮助临床医生就是否可以在接受HBOT的患者身上安全使用哪些外用产品做出更合理的决定。
温德尔·赫尔联合公司进行了独立研究，比较了主要护肤品的氧兼容性。使用自燃温度（AIT）、氧指数（OI）和燃烧热（HoC）测试来确定氧兼容性。AIT是材料着火倾向的相对指标，是在给定压力和氧浓度下使样品自燃所需的最低温度。OI是材料可燃性的相对指标，是与氮气混合时能维持燃烧的最低氧百分比。HoC是材料燃烧时（如果发生着火）能量释放的绝对值。在富氧环境（OEA）中，AIT高、OI高且HoC低的产品更具兼容性。根据这三个因素为产品计算了一个可接受性指数（AI），以便测试人员可以对OEA中的整体材料兼容性进行排名（拉平A.材料的氧兼容性。国际制冷委员会会议；英国布莱顿；1973年）。
皮肤产品的测试结果差异很大。在所述情况下确定了每种产品的AIT、OI、HoC和AI。AIT结果表明，在压力下99.5%氧浓度下的所有产品都会着火，并且基于是否存在石油基成分的模式似乎不存在。含有凡士林、矿物油、石蜡和石蜡的产品的HoC等于或超过汽油的HoC，而不含石油基成分的产品的HoC则显著较低。不含石油基成分的皮肤产品的OI显著高于含该成分的产品。AI将OI视为最重要的值：AI越高，产品在氧气环境中使用就越可接受。含硅酮、无石油的产品的AI比含凡士林的产品高出25倍。这些发现表明皮肤产品的安全概况存在很大差异。应筛查考虑在OEA中使用的皮肤产品的可燃性风险。这种筛查将有助于就产品的消防安全做出明智的决定。需要进一步研究。
