Does portal nutrition benefit liver protein synthesis?

There are only a few experimental investigations on the feasibility and potential advantages of intraportal nutrition in animals and only two uncontrolled studies in humans. The purpose of this study was to compare some metabolic variables in patients who received portal or systemic nutrition after elective surgery for colorectal cancer. Twenty patients were randomized to receive postoperatively for a week a hypocaloric, "protein sparing" standard infusion via the portal (catheter in the gastroepiploic vein) (10 patients) or systemic (10 patients) route. We evaluated the basal concentrations of some visceral and acute-phase proteins and their variations in the first postoperative week and the nitrogen balance. Statistical analysis was performed by the two-tailed Student t test. There was no difference in the daily changes of the visceral and acute-phase proteins after surgery in the two groups of patients, but in the portal group there was a significantly better recovery of the level of total protein, albumin, and cholinesterase at the end of the portal infusion vs the systemic group (p < or = .005, .03, and .02, respectively). In regard to the nitrogen balance, although there was no difference in the overall balance between portal and systemic nutrition, if we separate the acute phase of the injury from the later one we do not see any significant difference in the first period but we do see a highly significant advantage for the portal group during the last 2 days (p < or = .0001).(ABSTRACT TRUNCATED AT 250 WORDS)