Infection Control & Hospital Epidemiology
precautions, curtains are changed every 2 weeks and upon dis- charge. Curtains that have built-in antimicrobial properties, which are recommended to remain hanging in situ for 3–6 months, present an attractive option. In addition to removing curtains as a source of MDRO transmission, antimicrobial privacy curtains may also avert costs related to changing and laundering of standard curtains. However, few studies attest to the anti- bacterial action of such curtains throughout months of hanging in clinical areas. The aim of the present study was to determine the efficacy of antimicrobial privacy curtains in clinical settings and the costs involved in replacing standard curtains with anti- microbial curtains.
Methods Settings and study design
This open-labeled, prospective study was performed in the medical, surgical, neurosurgical, orthopedics, and rehabilitation units of 10 hospitals in the Hong Kong Special Administration Region, China, from November 2016 to November 2017. Two types of clinical settings were studied: (1) the rooms of patients with MDROs where antimicrobial curtains were changed upon discharge and (2) the cubicles of a ward where antimicrobial curtains hung for 3–6months, according tomanufacturers’ recommendations (except for the corner beds of cubicles where patients with MDROs resided, where curtains were changed upon discharge). Standard curtains were changed according to hospital policy. Commercially available antimicrobial curtains from 2 manufacturers were used in this study: antimicrobial curtain A (EcoMed Ultra built-in silver hospital disposable curtains, Ecomed, Hong Kong, China), made with nonwoven fabric impregnated with silver additives, and antimicrobial curtain B (Endurocide antimicrobial and sporicidal curtains, Aberdeenshire, Scotland, UK), made with a blend of quaternary ammonium chlorides (QAC) plus polyorganosiloxane. Standard curtains (100% polyester) were hung on the opposite side of the antimicrobial curtains. The study protocol was approved by the Institutional Review Board of the Hospital Authority, Hong Kong.
Microbial testing of privacy curtains
New antimicrobial and standard curtains were placed on day 0 of the trial. Because each curtain was shared between patients of 2 adjacent beds, culture samples were collected from all curtain surfaces twice per week for 2 weeks, followed by weekly intervals thereafter. An area 100cm×100cm on each leading edge of the curtain surface was sampled with a sponge (Polywipes, Medical Wipe and Equipment, Corsham, UK) from 70cm above the ground to 170cm above the ground. The sponge was immersed in 10mL Tryptone Soya Broth
(TSB) (Oxoid, UK). After vortexing for 30 seconds, 100 µL TSB was cultured aerobically at 35°C for 24–48 hours onto the fol- lowing agars:
1. MRSA chromagar (bioMèrieux,Marcy-l'Étoile, France) for MRSA 2. CHROMagar Acinetobacter (CHROMagar, Paris, France) for carbapenem-resistant Acinetobacter spp (CRA) and multidrug- resistant Acinetobacter spp(MDRA), which was definedas resistance to all 5 antimicrobial classes: fluoroquinolones, aminogly- cosides, cephalosporins, β-lactam and β-lactamase inhibitor combinations, and carbapenems
165
3. Tryptone Soya Agar (TSA) (Oxoid, UK) for total aerobic count (TAC)
The TSB was then incubated aerobically at 35°C. After overnight incubation, the TSB was subcultured onto CHROMagar Acine- tobacter for isolation of CRA and MDRA. Colony-forming units (CFU) were counted on each plate. Green
colonies on MRSA chromagar and red colonies on CHROMagar Acinetobacter were confirmed as S. aureus and Acinetobacter spp, respectively, by mass spectrometry (MALDI Biotyper, Bruker Daltonics, Germany). Antimicrobial susceptibilities were performed according to the guidelines set by the Clinical and Laboratory Standards Institute (CLSI).9 To ensure that the sampling process would not elute anti-
microbial substances from the antimicrobial curtain, new anti- microbial curtains were sampled and processed as above, with subsequent addition of bacteria pellets (S. aureus, Acinetobacter baumannii, and Pseudomonas aeruginosa)at104 CFU to the TSB. No inhibitory substances were found on the sampled sponge in the TSB, and there was no significant difference in the CFU of the inoculated bacteria upon subculture.
Data Collection
The direct costs (eg, new purchase) and indirect costs (eg, laun- dering, labor for changing, loss of avenue), in-use duration, and reasons for change of each piece of antimicrobial and standard curtain were recorded. The history of isolation of MRSA, CRA, and MDRA from clinical or screening specimens of the patients who resided in the study cubicles or in rooms was mapped to each curtain.
Statistical analysis
Results were analyzed both at the level of individual curtain and also individual curtain surface as the unit of analysis. The bivariable associations between curtain type and contamination were assessed with the independent-sample t test or the Mann– Whitney U test. Median time to first contamination was mea- sured in days, from the day each curtain was hung to the day the first sample had a positive MDRO culture result (ie, any MRSA, CRA, or MDRA). The time to first contamination by MDROs was also examined using a nonparametric maximum likelihood esti- mation (NPMLE) approach that extended the Kaplan-Meier survival analysis from right-censored survival time data to interval-censored survival time data. All analyses were performed using R version 3.1.2 software (R Foundation for Statistical Computing, Vienna, Austria). The interval package was used for survival analysis.
Results
Overall, 31 curtains were placed in the rooms of patients with MDROs (N=12; 668 patient bed days while curtains were hanging). Also, 290 were placed in 12 cubicles (8,839 patient bed days while curtains were hanging). The distributions of curtains by patient type, ward specialty, and hospital are presented in Table 1. The study in the orthopedics department (6-bed cubicle) of Queen Mary Hospital was terminated prematurely due to personnel changes of the infection control team. In addition, 12 pieces of antimicrobial curtain A were removed before the com- pletion of the study:
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131 |
Page 132 |
Page 133 |
Page 134 |
Page 135 |
Page 136 |
Page 137 |
Page 138 |
Page 139 |
Page 140 |
Page 141 |
Page 142 |
Page 143 |
Page 144 |
Page 145 |
Page 146 |
Page 147 |
Page 148 |
Page 149 |
Page 150 |
Page 151 |
Page 152 |
Page 153 |
Page 154 |
Page 155 |
Page 156
