A comparison of parenteral nutrition and early postoperative enteral feeding on the nitrogen balance after major surgery.

The nitrogen balance in 28 patients undergoing aortic grafting for aneurysm or occlusive disease was studied. Patients were randomized to receive after surgery either standard intravenous fluids (group 1), parenteral nutrition (group 2), or early postoperative enteral feeding (group 3). The mean daily negative nitrogen balance was 11.22 gm in group 1, 4.20 gm in group 2, and 4.14 gm in group 3. The difference between group 1 and groups 2 and 3 was highly significant (p less than 0.001), but there was no significant difference between groups 2 and 3. It is concluded that early postoperative enteral feeding can be as effective as parenteral nutrition in reducing the negative nitrogen balance induced by major surgery.