Antimicrobial prophylaxis in surgery: microbiological factors.

Various aspects of prophylaxis in surgery are discussed. The timing of antibiotic doses is analysed in relation to the Burke laboratory model and the lag-phase of bacterial growth. Areas where further data is required: the effect of locally applied antibiotics, protection against sources of organisms and new approaches to prophylaxis are discussed. The ecological effects of antibiotics are described in relation to prophylaxis.