Intestinal ischemia: Treatment by peritoneal lavage with oxygenated perfluorochemical

Though the delivery of elemental oxygen to tissues ravaged by anaerobic infection may be useful, little data exists that suggests that such therapy may benefit ischemic tissue. We report the development of a model to test the question that peritoneal lavage with an oxygen containing solution may favorably influence occlusive intestinal ischemia. Adult Sprague-Dawley rats with Nembutal (sodium pentobarbital) anesthesia underwent midline, laparotomy; a microvascular clamp was applied to the superior mesenteric artery (SMA); and an inflow and outflow lavage catheter was placed. Treatment groups included control rats undergoing SMA occlusion only without lavage, rats lavaged with albumin during SMA occlusion (medium control), and rats lavaged during SMA occlusion with oxygenated perfluorochemical FC-47 emulsified in albumin (O₂-FC-47). The increase in serum L-lactate following occlusion was used as an index of intestinal injury whether the perfusate was maintained at room temperature (28°C) or body temperature (37°C). Beginning with time O. which corresponded to the time of unclamping, subsequent samples were collected at 15, 30, and 60 minutes after a 30-minute SMA occlusion. Sequential lactates in 13 control rats were 4.18, 4.10, 3.88, and 4.52 mmol/L. Albumin lavaged animals had values at 28°C of 2.23, 1.35, 1.8, and 2.44 mmol/L and values at 37°c of 2.22, 1.40, 2.07, and 3.21 mmol/L, respectively. With O₂-FC-47 lavage the respective lactates were 1.89, 1.09, 1.32, and 1.44 mmol/L at 28°C and 2.14, 2.19, 2.50, and 2.1 mmol/L at 37°C. These data suggest that both volume expansion and lower core temperature minimize the degree of occlusive intestinal injury. Of striking importance is the impact of lavage with O₂-FC-47 as noted at one hour postocclusion. The statistically significant (P<.05) reduction in lactate suggests that the application of elemental oxygen via perfluorochemical lavage may retard the progression of ischemic intestinal injury.