Enteral nutrition is superior to total parenteral nutrition for the treatment of grade B postoperative pancreatic fistulas, reported Dr. Stanislaw Klek and his colleagues in the July issue of Gastroenterology.
Indeed, not only does enteral nutrition facilitate fistula closure, but closure occurs more quickly and the enteral approach is less costly, wrote the researchers (Gastroenterology 2011 July [doi:10.1053/j.gastro.2011.03.040]).
Dr. Klek of the Jagiellonian University Medical College in Krakow, Poland, and his associates studied 78 adult patients with postoperative pancreatic fistula treated at a single academic center in Poland. All patients had a grade B fistula, according to the criteria of the International Study Group on Pancreatic Fistula. "Postoperative pancreatic fistula is the most common and potentially life-threatening complication after pancreatic surgery," they noted.
Patients were excluded if they had any cardiocirculatory, pulmonary, renal, or liver failure; if their fistula required surgical intervention; or if nutritional status was so depleted that it required both parenteral and enteral feeding.
Patients were randomized into two demographically similar groups; for 30 days, one group received enteral feeding while the other received total parenteral nutrition (TPN). All patients were treated conservatively without surgery, somatostatin analogues, or proton pump inhibitors.
Enteral feedings were started 2-4 hours after placement of a nasointestinal tube, located 20 cm below the Treitz’s ligament or, in the case of pancreaticoduodenectomy, 20 cm below the last jejeunal anastomosis. The formula, called Peptisorb (manufactured by Nutricia), contains 1 kcal/mL, is low in fat, and is peptide based, with an initial flow rate of 10 mL/hr, progressing up to 125 mL/hr.
Parenteral nutrition infusions also commenced 2-4 hours post insertion of a central venous catheter, and were prepared by the hospital pharmacy.
The mean age in both groups was 57 years, and almost half (45%) of each group was female.
Fistula closure was defined as an output of less than 10 mL during a 48-hour period, with no recurrence in the subsequent 30 days and no evidence of fluid collection on ultrasound or computed tomography scan.
At 30 days, the rate of fistula closure was 60% in the enteral group (24 of 40 patients) and 37% in the parenteral group (14 of 38 patients).
That amounted to an odds ratio of 2.57 for the probability to be a responder with enteral feedings, compared with TPN (95% confidence interval, 1.03-6.41; P = .043).
The authors analyzed the data to identify other variables that might predict fistula closure, including demographic information, diagnosis (pancreatic cancer, ampullary cancer, or other); concomitant disease; body mass index; baseline lymphocyte and albumin levels; weight loss; type of surgery; and fistula output (less than 200 mL/day versus 200 mL or greater).
In this stepwise logistic regression analysis, "only two factors were significantly associated with fistula closure," wrote the authors. They were enteral nutrition (OR, 6.1; 95% CI, 1.2-41.6, P = .043) and initial fistula output of 200 mL/day or less (OR, 12.7; 95% CI, 9.1-47.2, P less than 0.001).
The researchers also looked at median time to closure. In the enteral nutrition cohort, it was 27 days (95% CI, 21-33 days). No median time was reached in the parenteral group (P = .047).
Cost was significantly lower for the enteral patients, with the median 30-day price tag for nutritional intervention being $532 for the enteral group and $968 for the parenteral cohort (P less than .001).
Fistula recurrence was found in two TPN patients, at 8 and 31 days after TPN withdrawal. No recurrence was seen in the enteral group. Both treatments were without major complications or safety issues, except for two cases of bacteremia in the TPN cohort, plus one case of diarrhea in the enteral group.
Although evidence-based recommendations for nutritional support in the setting of a postoperative pancreatic fistula are currently limited, "fasting with nutritional support, along with adequate drainage and skin protection, are currently the basic aspects of treatment," wrote the authors.
However, prior to this study, the choice between TPN and enteral feedings has been "essentially arbitrary, because the effects of both diets on closure rates of postoperative pancreatic fistula have not been compared in a randomized clinical trial."
Dr. Klek and his coauthors postulated that the benefits of enteral feeding are likely related to its stimulation of the release of "specific gut peptides, forming a negative feedback control system, and thus inhibiting pancreatic secretion." They added, however, that the mechanisms of this negative feedback loop are poorly defined.
Dr. Klek reported receiving educational and research grants from Nutricia, maker of the enteral formula used in this study, as well as Fresenius Kabi and B Braun, which make enteral and parenteral products, respectively. The study was also funded by Nutricia.