Zukowski M L, Lord J L, Ash K
Department of Plastic and Reconstructive Surgery, Naval Medical Center, Portsmouth, Virginia, USA.
Burns. 1998 Jun;24(4):374-7. doi: 10.1016/s0305-4179(98)00029-1.
Warming lights, circulating-water blankets, space heaters, and the Bair Hugger are used by surgeons in the perioperative period to maintain a patients core body temperature. Warming lights in particular are often used by plastic surgeons to augment the postoperative vasodilatation of reconstructive flaps by increasing the ambient temperature of the area around the flap. A review of the literature fails to elucidate even anecdotal experience regarding the actual intensity of thermal energy directly imparted to tissues from these modalities with respect to distance. The purpose of our study was to quantify actual tissue temperatures generated, as a function of distance, with the Emerson warming light. Our interest in this is a result of a full-thickness burn which occurred to a portion of a pedicled TRAM flap used for breast reconstruction when a warming light was inadvertently positioned, during the course of the first postoperative night, at a distance less than that recommended by the manufacturer. A biological model was created simulating a sympathectomized flap and the temperature curves generated by Emerson warming lights were recorded by calibrated glass bulb thermometers at 15 min intervals for distances of 32 and 71 cm using both focused and defocused light beams. The distance of 32 cm was used as a parameter as it was the distance noted between the patient and the warming light when the TRAM flap burn occurred. Temperatures obtained at a distance of 32 cm rose to 120 degrees F (48.8 degrees C) within 30 min for the focused beam and 118 degrees F (48 degrees C) after 1 h for the defocused beam. This exceeds the temperature at which tissue necrosis is known to occur (111.2 degrees F/44 degrees C). However, temperatures obtained at 71 cm for the focused and defocused beams plateaued at 93.2 and 96.8 degrees F (34 and 36 degrees C) respectively, which is well within physiologic limits and below the temperature resulting in tissue necrosis. Our conclusion is that warming lights can be successfully used as a safe adjuvant in order to optimize flap vasodilatation without compromising the thermal threshold of tissue damage if maintained at the manufacturer's minimum recommended distance of 71 cm. If this source of thermal energy is used, however, strict precautions and nursing guidelines must be instituted to maintain this minimum distance parameter and prevent patient morbidity.
在围手术期，外科医生会使用暖灯、循环水毯、空间加热器和百特保暖仪来维持患者的核心体温。特别是整形外科医生，经常使用暖灯，通过提高皮瓣周围区域的环境温度，来增强重建皮瓣术后的血管扩张。查阅文献发现，对于这些方式直接传递给组织的热能实际强度与距离之间的关系，甚至连轶事性的经验都没有。我们研究的目的是量化艾默生暖灯产生的实际组织温度与距离的函数关系。我们对此感兴趣是因为在一次乳房重建手术中，一个带蒂横行腹直肌肌皮瓣（TRAM瓣）的一部分发生了全层烧伤。在术后第一个晚上，一盏暖灯无意中被放置在距离皮瓣小于制造商推荐的距离处。我们创建了一个模拟去交感神经支配皮瓣的生物模型，使用校准的玻璃泡温度计，以15分钟为间隔，记录了使用聚焦光束和散焦光束时，在32厘米和71厘米距离下艾默生暖灯产生的温度曲线。32厘米的距离被用作一个参数，因为这是TRAM瓣烧伤发生时患者与暖灯之间记录到的距离。对于聚焦光束，在32厘米距离处，温度在30分钟内升至120华氏度（48.8摄氏度）；对于散焦光束，1小时后温度升至118华氏度（48摄氏度）。这超过了已知会发生组织坏死的温度（111.2华氏度/44摄氏度）。然而，在71厘米距离处，聚焦光束和散焦光束的温度分别稳定在93.2华氏度和96.8华氏度（34摄氏度和36摄氏度），这完全在生理限度内，且低于导致组织坏死的温度。我们的结论是，如果将暖灯保持在制造商推荐的最小距离71厘米，那么暖灯可以成功用作一种安全的辅助手段，以优化皮瓣血管扩张，而不会损害组织损伤的热阈值。然而，如果使用这种热能来源，必须制定严格的预防措施和护理指南，以维持这个最小距离参数，防止患者出现并发症。
