EFFECTS OF ENDOGENOUS ABSORPTION IN HUMAN ALBUMIN SOLDER FOR ACUTE LASER WOUND CLOSURE

Background and Objective: Human albumin is currently being used as a b iological solder in laser tissue welding. Experiments were performed t o characterize the effects of differing albumin concentrations on woun d closure when a 1.32 mu m Nd:YAG laser is used to repair skin incisio ns. Materials and Methods: In vivo comparison of acute tensile strengt h was made in full thickness porcine skin wounds using different solde r concentrations, Histology of the repairs was also completed to evalu ate the thermal denaturation of the tissue and solder. Transmission me asurements were completed for nondenatured and denatured albumin solde rs. Finally, the real time denaturation pattern of different solder co ncentrations during laser irradiation was investigated, Results: A tis sue solder consisting of 50% albumin provides the greatest tensile str ength for acute in vivo skin closure. The transmission measurements ve rify that the primary absorber of 1.32-mu m laser light was the solder solvent (water), A significant decrease in power transmission occurs when the 25% albumin solder was denatured. The real time denaturation profiles demonstrate that 1.32-mu m laser light denatures 25% albumin solder from the outer surface, while in 50% albumin solder, denaturati on occurs from within the solder bulk. Wound histology corroborates th e pattern of denaturation seen in vitro. Conclusion: The combination o f 1.32-mu m laser light and 50% human albumin solder can be used to cr eate a deep tissue weld resulting in higher acute repair tensile stren gth. This permits a deep to superficial closure of wounds, which may r esult in an optimal method of acute closure for full-thickness wounds. Lasers Surg. Med, 23: 18-24, 1998. (C) 1998 Wiley-Liss, Inc.