Biocleaning in operating theatres: validation of cleaning techniques by revealing residual traces of blood

Abstract

In the operating theatre the biocleaning process is essential after each passage to guarantee the non-transmission of potentially pathogenic microbial agents from patient to patient. To evaluate the quality of this biocleaning, the Operational Hygiene Team used a very sensitive method to detect residual traces of blood: luminol (3-aminophthalhydrazide) on the basis of methods used by the police. Luminol was used after conventional one-step biocleaning with the usual detergent/disinfectant, after bleach disinfection before biocleaning, and after biocleaning with a steam cleaner. Lunimol revealed extended traces of blood corresponding to the passage of the strip on the floor, in the corners of the room and on certain pieces of furniture which are difficult to clean. However, no luminescence was detected on the surfaces cleaned by a single passage of the steam cleaner. In all cases, the rooms appeared visually clean and traces of blood only became visible when revealed by luminol. We also showed that usual detergents or disinfectants do not remove blood and instead actually spread it over surfaces that may seem visually clean. These results led us to modify our procedure and also confirmed our wish to generalize the use of the steam cleaning technique for immediate cleaning. Furthermore, our tests show the relevance of luminol as a validation tool for the quality and method of biocleaning.