Influence of parenteral nutrition on postoperative recovery in an experimental model of peritonitis

Background and aims: There seems to be no clear-cut indications for routine TPN support after major elective surgery. The present study was designed t o investigate whether TPN could improve the results of standard surgical ca re for acute peritonitis (laparotomy plus antibiotics). Animals and methods : Peritonitis was induced in 48 New Zealand rabbits (day -2). On day 0, app endectomy and peritoneal lavage were performed, ceftriaxone (250 mg, i.m./2 4 h.) was started and animals were randomly assigned to receive regular flu ids (RF), glucose-based TPN (G-TPN) or isocaloric fat-based TPN (F-TPN) for 6 days. Main outcome measures Balance studies (days 1-3), s-albumin, thyro id hormones and urinary catecholamines were determined at various points of the experiment. At postmortem, wound infection, residual intra-abdominal i nfection and laparotomy wound breaking strength were recorded. Results: Per itonitis produced a fall in weight, s-albumin and T3. At day 6, weight-loss was more pronounced in RF than in G-TPN or F-TPN (-7 vs 1.5 vs -1.2 %; P= 0.0001) but s-albumin and T3 concentrations were similar. Diuresis (377 vs 268 vs 269 mL/3 days; P= 0.01) was higher and water balance lower (373 vs 5 11 vs 480 mL/3 days; P = 0.01) in Group RF. Although the differences were n ot statistically significant (P < 0.2), persistent infection and wound brea king strength were slightly worse in the pooled TPN groups compared with th e RF group (19 vs 6% and 542 vs 701 g, respectively). Conclusions: TPN fail ed to improve relevant biochemical markers and clinical outcome after lapar otomy for peritonitis. (C) 2001 Harcourt Publishers Ltd.