The critical relationship between airborne microbiological contamination in an operating theatre and surgical site infection (SSI) is well known. The aim of this annotation is to explain the scientific basis of using settle plates to audit the quality of air, and to provide information about the practicalities of using them for the purposes of clinical audit. The microbiological quality of the air in most guidance is defined by volumetric sampling, but this method is difficult for surgical departments to use on a routine basis. Settle plate sampling, which mimics the mechanism of deposition of airborne microbes onto open wounds and sterile instruments, is a good alternative method of assessing the quality of the air. Current practice is not to sample the air in an operating theatre during surgery, but to rely on testing the engineering systems which deliver the clean air. This is, however, not good practice and microbiological testing should be carried out routinely during operations as part of clinical audit. Cite this article:
Patient warming significantly decreases the risk
of surgical site infection. Recently there have been concerns that forced
air warming may interfere with unidirectional airflow, potentially
posing an increased risk of infection. Our null hypothesis was that
forced air and radiant warming devices do not increase the temperature
and the number of particles over the surgical site when compared
with no warming device. A forced air warming device was compared with
a radiant warming device and no warming device as a control. The
temperature and number of particles were measured over the surgical
site. The theatre was prepared as for a routine lower-limb arthroplasty
operation, and the same volunteer was used throughout the study. Forced air warming resulted in a significant mean increase in
the temperature (1.1°C
