Studies in the management of the contaminated wound: IX. Quantitation of the evans blue dye content of open and primarily closed surgical wounds

Abstract

The purpose of the present study was to quantitate the changes in the vascular permeability of open and primarily closed wounds after bacterial contamination. Alterations in vascular permeability in tissue were indicated by measuring the content of Evans blue dye in open and primarily closed wounds at different intervals after wounding and contamination. Evans blue dye forms a stable complex with circulating plasma albumin and extravasates through the walls of vessels as they become increasingly permeable. One hour after wounding, the tissue in the clean open wound exhibited a marked increase in dye content when compared with primarily closed wounds not subjected to bacterial contamination. The elevated dye content in the open wound persisted at least seventy-two hours after wounding. Contamination of the open wound with Staph aureus resulted in minimal changes in the content of dye when compared with open wounds not subjected to contamination. In contrast, topical application of Staph aureus to the surface of a wound undergoing primary closure elicited a marked increase in the Evans blue dye content of the primarily closed wound. It is postulated that the increase in Evans blue dye in the clean open wound is a reflection of extravasation into the wound of plasma proteins that form a serous exudate. This accumulation of blood proteins in the open wound may account for its resistance to infection by providing either local lymphatic blockades to bacterial invasion, wound drainage for removal of foreign bodies, antibacterial activity that renders the wound free of bacteria, or all of these factors.