Postoperative protein sparing

Postoperative nitrogen sparing refers to a therapy that decreases net nitro gen loss from the body following an operation. Protein sparing has long bee n regarded as a surrogate marker for improved outcome, but a critical revie w of the evidence indicates that this relation is difficult to establish, e specially in the short term. Thus, specific endpoints that evaluate outcome are needed to determine the efficacy of a specific therapy that spares pro tein. Cost effectiveness must also be considered. A variety of therapies we re evaluated using protein sparing, efficiency, and cost criteria. Evidence was reviewed for glucose, amino acids, parenteral nutrition, enteral nutri tion, growth hormone, and glutamine administered during the perioperative p eriod. Only three areas could be identified that spared nitrogen and provid ed efficacy: (1) preoperative total parenteral nutrition (TPN) for 7 to 10 days before operation in a depleted patient (less than or equal to 15% body weight loss); (2) the use of growth hormone with nutritional support to pr omote wound healing (especially in burns) and possibly to enhance muscle st rength (particularly in the elderly); and (3) the use of glutamine-suppleme nted 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 improve d outcomes and enhanced cost saving with our protein-sparing therapy can we continue to enhance the care of our surgical patients.