Increased Gut Permeability Following Burn Trauma

Abstract
• Twenty female Hartley guinea pigs, weighing 350 to 400 g, were given a 30% full-thickness burn injury. Gastrointestinal permeability was assessed before burn and on postburn days 1 through 3, 7, and 14 by administering 5 mL of an isotonic mixture of 8% lactulose and 1.15% L-rhamnose by gavage and measuring the urinary excretion for the next 7 hours. In normal guinea pigs, lactulose (molecular weight, 342d) is mostly absorbed by the paracellular route, whereasL-rhamnose (molecular weight, 164 d) is mostly absorbed by the transcellular route. Gut permeability tol-rhamnose did not increase after burn injury (211 μg before burn vs 230, 260, 180, 238, and 221 μg on days 1, 2, 3, 7, and 14, respectively, after burn). By contrast, gut permeability to lactulose increased significantly and was greatest in the first 48 hours after burn injury (60 μg before burn vs 380, 354, 203, 364, and 279 μg on days 1, 2, 3, 7, and 14, respectively, after burn). Gut permeability to low-molecular-weight compounds increases immediately after burn trauma, and this may be by a paracellular rather than transcellular mechanism. (Arch Surg. 1991;126:198-200)