Microvascular changes of sludging and stasis are indications of thermal injury in tissue. This study investigates whether microvascular thermal injury can be decreased via topical application of poloxamer-188. Rat mesenteric microvessels were thermally injured and topically suffused with either Ringer's solution (control) or 5% poloxamer-188 in Ringer's solution (experiment). Blood flow was characterized in microvessels as normal or abnormal (ie, sludging and stasis). Topical treatment with poloxamer-188 reduced the percentage of capillaries with abnormal blood flow from 62% to 23%. In venules, this treatment resulted in a decrease from 54% to 34%. These results demonstrated that topically applied poloxamer-188 dramatically reduces the microvascular changes of sludging and stasis because of thermal injury in rat mesenteric microvessels.