Aseptic Technique: a Review of the Literature

Humans have adapted over time to live in a microbially dominated world and developed the nonspecific and specific immune systems required to cope with contamination by microorganisms. Sources of microbes for wound infection can be divided into endogenous and exogenous groups. The endogenous organisms already colonise the skin, orifices and cavities of the patient and their total on and in the body outnumber human cells by a factor of at least ten (Cooper, 2005). Microorganisms from beyond the patient’s body, whether they are from another person, animals, equipment or the wider environment, are called exogenous organisms. Generally speaking, planned closed surgical wounds should be presumed to contain little or no contamination from either of these sources, but wounds healing by secondary intention will have a diverse colonisation of organisms, known as a bioburden. In these open wounds, if there is progression in the direction of healing, it is reasonable to presume that this bioburden is being kept in a suitably healthy balance by the immune system. Andrew Kingsley is Clinical Manager Infection Control and Tissue Viability, Northern Devon Healthcare Trust