Measurement of Burn-Induced Leakage of Macromolecules in Living Tissue

Abstract

An experimental technique has been developed to measure changes in vascular permeability caused by thermal trauma to the microvascular bed of the hamster cheek pouch. A solution of flourescein isothiocyanate (FITC) conjugated dextran was injected directly into the circulatory system. Subsequent leakage of dye from vessels into the extravascular space was directly observed by light microscopy and recorded by sequential photography. Individual frames of the filmed record of the trauma and post-trauma process were digitized and analyzed by computer. A point-by-point densitometric evaluation of the digitized image provides a measure of extravascular accumulation of dye-tagged dextran. Preliminary results indicate that preburn treatment with large doses of heparin yields a significant reduction in burn-induced edema.