Wilmore D W
Laboratories for Surgical Metabolism and Nutrition, Department of Surgery, Harvard Medical School, Brigham and Women's Hospital, 75 Francis Street, Boston, Massachusetts 02115, USA.
World J Surg. 1999 Jun;23(6):545-52. doi: 10.1007/pl00012345.
Postoperative nitrogen sparing refers to a therapy that decreases net nitrogen loss from the body following an operation. Protein sparing has long been regarded as a surrogate marker for improved outcome, but a critical review of the evidence indicates that this relation is difficult to establish, especially in the short term. Thus, specific endpoints that evaluate outcome are needed to determine the efficacy of a specific therapy that spares protein. Cost effectiveness must also be considered. A variety of therapies were evaluated using protein-sparing, efficiency, and cost criteria. Evidence was reviewed for glucose, amino acids, parenteral nutrition, enteral nutrition, growth hormone, and glutamine administered during the perioperative period. Only three areas could be identified that spared nitrogen and provided efficacy: (1) preoperative total parenteral nutrition (TPN) for 7 to 10 days before operation in a depleted patient (</=15% body weight loss); (2) the use of growth hormone with nutritional support to promote wound healing (especially in burns) and possibly to enhance muscle strength (particularly in the elderly); and (3) the use of glutamine-supplemented TPN in severely ill surgical patients to decrease mortality. The issue of early tube feeding in trauma patients is still confusing. This therapy must be evaluated by an appropriate study in trauma patients that compares a tube-fed group with an unfed control group. Only by demonstrating improved outcomes and enhanced cost saving with our protein-sparing therapy can we continue to enhance the care of our surgical patients.
术后氮保留是指一种可减少术后机体净氮损失的治疗方法。长期以来，蛋白质保留一直被视为预后改善的替代指标，但对相关证据的严格审查表明，这种关系很难确立，尤其是在短期内。因此，需要有评估预后的特定终点来确定某种特定蛋白质保留疗法的疗效。成本效益也必须予以考虑。使用蛋白质保留、效率和成本标准对多种疗法进行了评估。对围手术期给予的葡萄糖、氨基酸、肠外营养、肠内营养、生长激素和谷氨酰胺的证据进行了审查。仅确定了三个能保留氮并具有疗效的领域：（1）在营养不良患者（体重减轻≤15%）术前7至10天给予全胃肠外营养（TPN）；（2）使用生长激素并辅以营养支持以促进伤口愈合（尤其是烧伤患者），并可能增强肌肉力量（特别是老年患者）；（3）在重症外科患者中使用添加谷氨酰胺的TPN以降低死亡率。创伤患者早期管饲的问题仍不明确。这种疗法必须通过一项针对创伤患者的适当研究来评估，该研究将管饲组与未进食的对照组进行比较。只有通过证明我们的蛋白质保留疗法能改善预后并提高成本效益，我们才能继续加强对外科患者的护理。
