Background: Colonic digestion has been reported to salvage up to 3-4 MJ/day in short-bowel patients (approximately 50% of the daily requirements).
Methods: A cross-sectional study of the parenteral support given to a total cohort of 73 patients receiving home parenteral nutrition (HPN) in Denmark on 31 December 1995 was performed to evaluate the significance of a preserved colon for the prevalence of short-bowel patients in need of HPN and the requirements of energy given as HPN. The number of HPN patients with a substantial remnant colon (> or =50%) was compared with the number with no colonic function (0%) in subgroups of patients with remnant small bowels of <100 cm (group 1), 100-200 cm (group 2), and >200 cm (group 3). Patients with pseudo-obstruction (n = 8) and patients with <50% colon remaining (n = 11) were excluded from the analysis. The impact of a substantial preserved colonic function (> or =50%) on the parenteral energy requirements was evaluated in patients with comparable lengths of small bowel.
Results: Twelve and 8 patients in group 1 had no colon and > or =50% colon in function, respectively, in contrast to patients in group 2, in which 21 had no colon in function and only 2 had >50% in function (Fisher's exact test, P = 0.028). In patients in group 1 the need for parenteral energy in percentage of basal energy expenditure (HPN/BEE%, mean +/- standard deviation) was 110 +/- 31% in patients with no colon and 59 +/- 31% in patients with a preserved colon (P = 0.001). In patients without a colon in groups 2 and 3 the HPN/BEE% was 58 +/- 45% and 33 +/- 47%, respectively.
Conclusions: Preservation of a substantial colonic function (> or =50%) is rare in patients in need of HPN with >100 cm remnant small bowel and results in a reduction in the parenteral energy requirements of approximately 3 MJ/day (51% of BEE) in patients with <100 cm small bowel. These data reinforce the reports of the colon as an energy-salvaging organ (approximately 3-4 MJ/day), which makes HPN unnecessary in most patients in whom small-bowel length is sufficient (>100 cm) to absorb another 3-4 MJ/day.