烧伤营养需求量需要调整：烧伤伤口渗出物提示微量元素补充不足和铝超负荷
严重烧伤患者随渗出液流失大量的微量元素，呈现微量元素急性缺失状态并导致一系列不良后果，但是人工营养支持及液体复苏可导致铝中毒。
瑞士洛桑大学医院烧伤中心重症监护病房（ICU）通过新的检测技术，收集并检测15例严重烧伤患者（平均烧伤面积29.1%）的渗出物及血浆中微量元素的含量。
结果发现，尽管接受了推荐剂量营养支持，严重烧伤患者因过多体液丧失，血液中的微量元素处于或低于正常范围下限，如铜、锌等，而血液中的硒含量过高。此外，渗出液、血清中的铝含量均超标（45±47、34±37μg/L）。
因此，针对重度烧伤患者，营养支持配方应考虑到微量元素失衡情况进行适当调整。
JPEN J Parenter Enteral Nutr. 2017;41(2):279.
Revision required in burn nutrition needs: insufficient trace element supplementation and aluminum loading revealed by burn wound exudate.
Paris Jafari, Olivier Pantet, Marc Augsburger, Aurelien Thomas, Wassim Raffoul, Lee Ann Applegate, Mette M. Berger.
Lausanne University Hospital, Lausanne, Switzerland.
PURPOSE: Severely burned patients develop major metabolic alterations with an intense inflammatory response that increase their nutrient requirements to face massive tissue repair. Exudative losses of various nutrients, including trace elements (TEs), complicate the assessment of their requirements and have been shown to cause acute deficiencies. Moreover, artificial nutrition and liquid resuscitation potentially expose major burn patients to aluminum toxicity. We aimed at measuring with actual analytical methods the exact TE content of exudates to improve the TE repletion strategy and evaluate potential Al loading in our burn patients.
METHODS: Inclusion of patients admitted to the burn intensive care unit (ICU) of the Lausanne burn center. Exclusion criteria: age <18 years, infectious comorbidities. Intravenous TE administration was by protocol. Exudate collection: the wound bed was covered with an occlusive dressing with a silicon drain placed underneath and connected to a sterile collecting bottle, submitted to mural suction and a continuous negative pressure (–125 mm Hg). Sampling was done by changing the reservoir twice daily and the dressing change every 48–72 hours. Seventy different elements were measured in the samples by inductively coupled plasma mass spectrometry (ICP-MS). Losses were normalized for burned surface. Dial Blood sampling for TE determination.
RESULTS: Fifteen patients aged 44.4 years (mean), burned 29.1% total body surface area (TBSA) were included. Average exudation period was 5.5 days (3–8 days) with maximum losses between days 1 and 4 posttrauma. Serum levels of Zn and Cu were below or in the lower limit of normal reference ranges despite administration of doses above recommendations. A maximum of 28% exudative loss of intravenous (IV) supplemented doses was observed for Se. Mg and Br were found to be highly lost in burn exudate. High levels of Al were measured in exudate and serum (mean 45 ± 47 μg/L and 34 ± 37 μg/L, respectively).
CONCLUSIONS: We had previously analyzed the exudative losses of 3 TEs and shown the importance of the repletion of these elements after major burns. Using new techniques, we recently analyzed the TE concentration in continuously collected exudates. We determined daily losses of 70 TEs, including essential TEs. This study shows that despite standardized IV administration of TEs, the serum levels only corrected to lower normal ranges for Cu and Zn, and Se levels increased too high in serum. Our data suggest that the supplementation protocols for Cu, Se, and Zn should be revised and adapted to the kinetics of exudative losses during the first week posttrauma. Moreover, several other essential TEs that are lost in high amount in exudates should be included in burn nutrition supplementation. High Al levels suggest more investigation to determine the source of this potentially problematic Al loading.
DOI: 10.1177/0148607116686023