Nutritional support and the surgical patient.

PURPOSE: Data on the impact of nutritional support (NS) on outcomes in surgical patients are reviewed.
SUMMARY: While most patients will progress to oral nutrition after surgery and require little or no intervention, major surgery or postoperative complications can delay the prescription of an oral diet. In such patients, nutritional requirements are often increased to support wound healing and hypermetabolism associated with surgical recovery. Without adequate nutrition, muscle wasting, immune dysfunction, and declining visceral protein status are observed. While it would seem intuitive that early nutritional intervention is warranted for most patients, the literature to date suggests that early parenteral nutrition (PN) does not improve clinical outcomes. An exception may be for severely malnourished patients if NS is provided for at least seven days preoperatively. Such patients should be identified early through nutritional assessment. Early enteral nutrition (EN) may potentially improve patient outcomes compared with PN, but there are insufficient data to confirm this. High-dose parenteral glutamine may reduce infectious complications and the length of hospitalization for surgical patients, but a significant reduction in mortality has not been observed. Early EN with immune-enhancing formulas appears promising for general surgery patients. However, their use in the critically ill surgical patient is not unanimously supported, and some studies suggest potential harm.
CONCLUSION: Surprisingly little evidence is available to support a significant impact of early NS on postoperative clinical outcomes.