Usage of aerosol sprays for disinfection of hospital rooms
Quality and efficacy of environmental (hospital) object disinfection performed using chemical disinfectant solutions depend on contact between the active agent and the opportunistic microorganisms on the contaminated surfaces, severity of contamination, and also composition of the disinfectant, its concentration, and time of exposure.
To compare results of terminal disinfection performed by using an aerosol generator (“an automated method”), or applying a backpack sprayer (“a manual method”).
From 06.2018 to 08.2018, the two aforementioned methods were used to spray disinfecting agents in the rooms of Raisa Gorbacheva Memorial Research Institute for Pediatric Oncology, Hematology and Transplantation. An aerosol generator and disinfectant “Nocolyse” composed of hydrogen peroxide (6%), nonionic surfactant (1%), and containing silver ions, were used to perform automated aerosol disinfection. A backpack sprayer filled with disinfectant “Amixan” containing nn-bis(3-aminopropyl) dodecylamine (3%), alkyldimethylbenzylammonium chloride plus alkyldimethylbenzylammonium chloride (25%) was used for manual disinfection. While using automated method, three operation modes were tested: 1:1 (1 ml of “Nocolyse” per 1 cubic meter), as well as 1 per 3, and 1 per 6 cubic meters. Test swabs from enviromental objects were taken before treatment (to determine total microbial counts), and after terminal disinfection (to evaluate efficacy of the procedure).
(1) Terminal disinfection by aerosol generator, 1:1 mode (5 cases). Sanitary and bacteriological tests showed presence of the following microflora (before and after the procedure respectably): E. coli, 3 (15%) vs E.coli, 0; Pseudomonas spp., 3 (15%) vs Pseudomonas spp., 1 (8.3%); Klebsiella pneumonia, 3 (15%) versus K.pneumoniae, 0; Acinetobacter spр., 1 (5%) vs – Acinetobacter spр., 1 (8.3%); Staphylococcus epidermidis, 7 (35%) vs S.epidermidis, 9 (75%); Enterococcus faecium, 1 (5%) vs E. faecium, 0; Bacillus, 2 (10%) vs Bacillus, 1 (8.3%). Microbiology with 1 to 3 mode (3 cases) has shown: Pseudomonas spp., 1 (6.7%) vs Pseudomonas spp., 0; Staphylococcus epidermidis, 8 (53.3%) vs S. epidermidis, 8 (88.9%); Klebsiella pneumonia, 2 (13.3%) vs K. pneumonia, 0; Bacillus, 3 (20%) vs Bacillus, 1 (11.1%); Staphylococcus aureus, 1 (6.7%); S. aureus, 0.
1:6 mode (2 cases). Microbiological findings were as follows: Staphylococcus epidermidis, 2 (40%) vs S.epidermidis, 1 (100%), Acinetobacter spр., 1 (20%) vs Acinetobacter spр., 0; Klebsiella pneumonia, 2(40%) vs. K. pneumoniae – 0. Meanwhile, manual disinfection (4 cases) yielded the following results: Klebsiella pneumonia, 1 (20%) vs K.pneumonia, 0; Acinetobacter spр., 2 (40%) vs Acinetobacter spр., 0; Pseudomonas spp., 1 (20%) vs Pseudomonas spp., 1 (33.3%); Enterobacter spр., 1 (20%); Enterobacter spp., 2 (66,7%). In cases of positive bacteriological tests, the disinfection procedure was repeated until the negative bacteriology results.
1. Automated method was not clearly confirmed to be more effective than the manual method.
2. Automated disinfection done at the 1:1 mode can be a good addition to routine disinfection.
3. Automated disinfection done at the 1:3 and 1:6 modes shows satisfactory results against the main disease-causing nosocomial pathogens, and it can be used as an alternative to the manual method.
We gratefully aknowledge Jaravina S. V. and Juravleva N. I., members of ICU №3 staff who helped us to organize our work.
Disinfection, hospital rooms, manual regimen, automatic regimen, bacteria, contamination.