To assess the extent of intestinal permeability following nonthermal i
njury ratios of lactulose and mannitol (L-M) concentrations in urine f
ollowing enteral administration were determined simultaneously by a ga
s-liquid chromatography assay on days 3, 5, 7, 10, and 13 in 15 patien
ts with an Injury Severity Score >20. Thirteen of 15 patients recovere
d uneventfully and two developed minor infections. L-M ratios were sig
nificantly increased on days 3-10 (P < 0.05 vs controls). The data are
consistent with previous studies describing early changes in gut perm
eability following nonthermal injury and show that altered permeabilit
y can persist for up to 10 days in patients with uneventful recoveries
. Published by Elsevier Science Ltd.