Effects of different disinfectants on decontamination of laryngoscopes.

Guidelines for controlling possible contamination of laryngoscopes should be formulated with the benefit of relevant experimental data. In this study, the effects of five different disinfectants commonly used for the disinfection of laryngoscopes are evaluated. We formed 14 groups, with 10 blades in each. The first 7 groups were contaminated with hospital related meticillin resistant Staphylococcus aureus (MRSA), and the remaining 7 groups with hospital related multiple resistant Pseudomonas aeruginosa (PA). For the first group of blades, no disinfection procedure was carried out and, were assumed as a control group. Blades in remaining groups were rested for 10 minutes in containers containing 70% alcohol (II), 1/100 dilution of cetrimide (III), 1/100 dilution of chlorhexidine (IV), 1/10 dilution of chlorhexidine (V), 1/10 dilution of povidone iodine (VI), and 1/100 dilution of ammonium chloride (VII). Disinfectant used in a group was considered effective when growth was seen in 5 or less than 5 plates representing that group. All disenfectants tested were found effective on decontamination of laryngoscopes. Five different moderate level disinfectants, which are commonly used for the disinfection of laryngoscopes, have been found effective even on resistant hospital microorganisms like MRSA and P. aeruginosa. They may be the choices of the disinfectants, especially 1/10 dilution of chlorhexidine gluconate and 1/100 dilution of ammonium chloride.