Quantitative evaluation of the bacteriostatic efficacy of amniotic membrane applied as a biological dressing over large contaminated wounds encountered in clinical practice

Summary Control of wound infection constitutes the most important aspect of wound management. A successful wound closure either by delayed primary/secondary suturing or by skin grafting cannot be performed unless the bacterial count in the tissues is well below the critical number of 10⁵ organisms per gram of tissue. In this study, the efficacy of the amniotic membrane in reducing bacterial infection when applied as a biological dressing over granulating wounds was compared with that of standard saline dressings. Bacteriological monitoring of wound flora was achieved by a three dimensional biopsy from an active portion of the infected wound. Such biopsies were taken from both test and control areas before membrane application and 72 h after application. The results of this study demonstrate that amnion dressings have a definite and significant antibacterial effect as seen by the marked decrease in bacterial colony counts after the dressing is applied to contaminated wounds. This effect of the amnion can be attributed to the intimate biological closure due to its excellent adherence on to the wound bed, facilitation of phagocytosis of the micro-organisms in the underlying healthier granulations and to certain antibacterial substances elaborated by the living amniotic cells.Presented at the Peet Prize Scientific Session of the 24th National Conference of the Association of Plastic Surgeons of India at Baroda, September 2, 1989