Terminal cleaning of hospital bed mattresses and bed decks does not eliminate bacterial contamination

BACKGROUND/OBJECTIVE: Hospital rooms undergo terminal cleaning prior to a new patient being placed in the room. Beds (including the mattress and bed deck) are cleaned and disinfected using a variety of chemical agents. Data are generally lacking on the bacteriologic effects of commercial cleaning agents that are used to disinfect mattresses and bed decks. The object of the study was to determine the extent to which hospital mattresses and bed decks are being disinfected. METHODS: All mattresses and bed decks entered into the study had been cleaned by housekeeping staff, who were aware of the study, using a solution containing Benzalkonium Chloride and Didecyl Dimethyl Ammonium Chloride (Sanimaster 4, Servicemaster of Canada, Mississauga, Ontario Canada). Flexible films coated with a thin layer of sterile solid nutrient medium (PetrifilmTM Aerobic Count Plates, 3M, Minneapolis, MN (film plates) were used to collect and quantify bacteria from the surfaces of hospital bed mattresses of a single community hospital. Prior to use, a 30 cm2 area of the medium on each film plate was hydrated with 0.9 milliliters of buffered peptone water broth. Mattresses were sampled by contacting the film plate to the mattress surface for 10 seconds, and the bed deck was sampled by placing the film plate on the bed deck for 10 seconds. Film plates were then incubated for 48 hours at 378C in 5-7% CO2. Film plates were then blotted onto BA, which was incubated as above. RESULTS: Thirty-nine mattresses and bed decks were sampled after undergoing terminal cleaning. Of the 39 mattresses sampled, 33 (84.6%) had bacteria detected. Colony forming units (CFU) per 30 cm2 ranged from 1 to too numerous to count (mean 7.3 +/-9.2 CFU). Of the 39 bed decks sampled, 22 (84.6%) had bacteria detected. CFU per 30cm2 ranged from 1 to 550 (mean 24.2 +/-89.7 CFU). Bacteria identified included: Staphylococcus species, Bacillus species, Gram-negative rods, and Micrococcus species. CONCLUSIONS: A commonly used cleaning agent and procedure for terminal cleaning of hospital mattresses and bed decks does not completely disinfect the mattress or bed deck. American Journal of Infection Control. 2011;39(5):E23.