Elsevier

Burns

Volume 43, Issue 2, March 2017, Pages 388-396
Burns

Pulsed-xenon ultraviolet light disinfection in a burn unit: Impact on environmental bioburden, multidrug-resistant organism acquisition and healthcare associated infections

https://doi.org/10.1016/j.burns.2016.08.027Get rights and content

Highlights

  • Pulsed xenon ultraviolet disinfection reduced environmental bioburden in a burn ICU.

  • This reduction was driven by decreases in skin commensal organisms.

  • No statistically significant changes in healthcare-associated infections were seen.

Abstract

Portable pulsed xenon ultraviolet disinfection (PPX-UVD) may reduce healthcare associated infections (HAI). There is limited data to inform use in burn intensive care units (BICU), where multidrug-resistant organisms (MDRO), especially gram negative rods (GNR), commonly cause disease. We evaluated PPX-UVD effects on environmental bioburden and rates of HAI and MDRO acquisition in a BICU. PPX-UVD was used for 3 months after standard cleaning of patient and operating rooms (ORs). Settle and touch plates in patient rooms and ORs were obtained after standard cleaning, pre-and post-PPX-UVD. HAI and MDRO acquisition were evaluated 1 year prior to and for 3 month periods before, during, and after PPX-UVD. 110 touch and settle plates (33 pre- and 30 post-PPX-UVD) were obtained after standard cleaning, pre- and post-PPX-UVD. After PPX-UVD, environmental samples with any growth decreased (48% vs 31%, p = 0.02), as did mean colony count/sample (2.8 pre- vs 1.6 post-, p = 0.03). The 379 colonies largely represented skin commensals, without identified MDRO. Following PPX-UVD, no changes in device-associated infections, overall MDRO, or MDR GNR were seen, though a prolonged interval without healthcare-associated Clostridium difficile infection was observed. PPX-UVD in a BICU reduced overall environmental bioburden, without a statistically significant impact on HAI or MDRO.

Introduction

Healthcare associated infections (HAI) are a major cause of morbidity and mortality worldwide. Critical illness and disruption of host defense mechanisms place burn patients at high risk of infections, particularly with gram negative rods (GNR), including multidrug-resistant organisms (MDRO) [1]. Infections account for the majority of deaths in patients who survive initial resuscitation [2], [3]. National Healthcare Safety Network (NHSN) data report higher baseline rates of HAIs in burn units compared to other types of intensive care units (ICUs) [4]. Staphylococcus aureus and GNR pathogens including Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae are commonly associated with infections in this population, with increasing rates of resistance over the course of hospitalization [5], [6]. Clostridium difficile infection has historically been less common in this center’s burn environment compared to other units, although rates have increased in recent years with introduction of PCR assays as well as changes in patient demographics to include more civilian transfer patients with complex wounds [7].

There has been much interest in the development of effective environmental disinfection strategies to prevent HAIs [8]. Contaminated surfaces act as reservoirs for pathogens, which can then be transmitted to patients. It is estimated that 20% of HAI may be driven by cross-transmission from the hospital environment, though these estimates may not apply to burn units, where patients’ wounds and the widespread use of invasive devices lead to high colonization and infection rates [9]. In a previous evaluation of environmental bioburden in this center’s burn unit, organisms have been cultured from 76% of environmental surfaces in occupied patient rooms [10]. A recent evaluation of airborne bacteria in a burn unit demonstrated significant dispersion created by bed and dressing changes, and numerous burn outbreak investigations have documented widespread environmental contamination with outbreak-strains of GNR including A. baumannii and P. aeruginosa [11], [12], [13]. Standard terminal cleaning involves manual application of chemicals to surfaces, which has numerous limitations, is prone to error, and up to 50% of surfaces may not be adequately disinfected during standard cleaning protocols [14]. Ultraviolet-C (UVC) light is broadly active against HAI pathogens, and no-touch devices using UVC generated by mercury or pulsed-xenon bulbs are becoming increasingly used as adjuncts to manual cleaning. Evaluations of UVC disinfection have demonstrated reductions in environmental pathogens, including methicillin-resistant S. aureus (MRSA), vancomycin-resistant enterococci (VRE) and C. difficile from hospital environment surfaces [15], [16].

Clinical data have also demonstrated reductions in infectious complications following implementation of UVC disinfection. One evaluation of UVC light disinfection hospital-wide resulted in a 53% reduction in healthcare associated C. difficile infections (HA-CDI), and another demonstrated a 70% reduction in HA-CDI cases in the ICU [17], [18]. Another study demonstrated an 87% reduction in ICU VRE rates, and a combined MDRO (including VRE, MRSA, and C. difficile) rate reduction of 61% [19]. However, no published data exist to date reporting on efficacy of portable pulsed-xenon ultraviolet disinfection (PPX-UVD) in burn units, either for reductions in environmental contamination or toward HAI or MDRO acquisition. Similarly, the role of PPX-UVD in reducing gram-negative infections has not been specifically evaluated.

Section snippets

Material and methods

The study entailed 2 aims. The primary aim was an evaluation of surface and air microbial contamination in inpatient rooms and ORs within an American Burn Association accredited burn center after standard cleaning, then before and after use of PPX-UVD. The secondary aim was an assessment of NHSN-defined HAI rates, MDRO acquisition, and clinical bioburden; the latter defined as all positive bacterial cultures from BICU patients in the time frames of interest. PPX-UVD was delivered after routine

Microbiology data

Nine inpatient rooms and 2 ORs had air (n = 63) and surface sampling (n = 110) before and after PPX-UVD (Table 1). Prior to PPX-UVD, samples from bathroom hoppers, bedside monitors and door handles were most heavily contaminated. After PPX-UVD, total samples (including both touch and settle plates) with any growth significantly decreased (48% vs 31%, p = 0.02), as did surface growth alone (51% vs 33%, p = 0.05). Including both air and surface samples, mean microbial density (heterotrophic plate count)

Discussion

In this study evaluating the impact of using PPX-UVD for a 3 month period in a burn ICU, we found that PPX-UVD significantly reduced environmental bioburden, which notably did not include MDROs after routine housekeeping. Numerous studies have demonstrated the contamination of hospital environmental surfaces by HAI pathogens, which can act directly as fomites for pathogen transmission or as a reservoir to contaminate hands of healthcare workers [22], [23], [24]. Epidemiologic studies have shown

Conclusions

This evaluation of PPX-UVD in a BICU setting revealed reductions in bacterial burden on the combined endpoint of high-touch environmental surfaces and air compared to terminal cleaning alone. This was driven by reductions in skin commensals, as no MDRO or GNR responsible for HAI were isolated from the environment, even before PPX-UVD. Statistically significant changes in clinical HAI and MDRO rates were not seen during this 3 month evaluation period compared to control periods, though the unit

Conflicts of interest

The authors endorse no conflicts of interest pertaining to the work described.

Disclaimer

The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or reflecting the views of the Department of the Army, Department of the Air Force, Department of Defense or the US government. This work was prepared as part of their official duties and, as such, there is no copyright to be transferred.

Funding

This research did not receive any grant from funding agencies in the public, commercial, or not-for-profit sectors.

Acknowledgments

The loan of a pulsed-xenon UVC light disinfection unit, education/training on use of the unit, support for third-party microbiology work at Central Texas Veterans’ Healthcare System, Temple, TX, and assistance with planning microbiology sampling procedures, were provided by Xenex Disinfection Services, San Antonio, TX. Microbiological sampling was performed by Douglas Johnson, LVN. The authors HY and JP were responsible for final study design, the authors reviewed and analyzed all study data,

References (37)

  • J. Still et al.

    Clostridium difficile diarrhea on a burn unit

    Burns

    (2002)
  • F. Barbut

    How to eradicate Clostridium difficile from the environment

    J Hosp Infect

    (2015)
  • J.P. Haas et al.

    Implementation and impact of ultraviolet environmental disinfection in an acute care setting

    Am J Infect Control

    (2014)
  • L. Fornwalt et al.

    Influence of a total joint infection control bundle on surgical site infection rates

    Am J Infect Control

    (2016)
  • L.K. Branski et al.

    Emerging infections in burns

    Surg Infect

    (2009)
  • J.W. Swanson et al.

    Trajectories to death in patients with burn injury

    J Trauma Acute Care Surg

    (2013)
  • J.H. Han et al.

    Cleaning hospital room surfaces to prevent health care-associated infections: a technical brief

    Ann Intern Med

    (2015)
  • D.J. Weber et al.

    The role of the surface environment in healthcare-associated infections

    Curr Opin Infect Dis

    (2013)
  • Cited by (29)

    • Automated room decontamination: report of a Healthcare Infection Society Working Party

      2022, Journal of Hospital Infection
      Citation Excerpt :

      However, one study [29] compared UV-C at every terminal discharge to UV-C only at terminal discharge of patients with C. difficile infection. Two of the studies reporting clinical outcomes were conducted as controlled trials [8,12], five were conducted as controlled before–after studies [20,28,30,33,37], seven were conducted as interrupted time series [13,15,24,27,29,34,38], and the remainder were conducted as quasi-experimental (uncontrolled before–after) studies [10,11,14,16–19,21–23,25,26,32,35,39]. Where controlled before–after studies reported adjusted IRRs these were used to calculate data inputs for the relevant NMAs (see Appendix H).

    • Potential of pulsed light technology for control of SARS-CoV-2 in hospital environments

      2021, Journal of Photochemistry and Photobiology B: Biology
      Citation Excerpt :

      These studies have been carried out mainly against bacteria, which hints about its potential effectivity against viruses. The efficacy of PL, alone or as a complement of standard cleaning with disinfectants, has been proved on personal protective equipment [67], respirators [67], touching surfaces of hospital units (surgical sites, isolation units, hematology and bone marrow transplant units) [69–72], hospital rooms [69,73–79], postdischarge patient isolation rooms [80] clinical laboratories [81], human milk feed preparation areas [82], operating rooms [83], intensive care units [80] and burn units [84]. Table 2 gives an overview of these studies which compiles results of case studies of heterogeneous nature where a PL system was used to disinfect a room.

    • Evaluation of a pulsed xenon ultraviolet light device for reduction of pathogens with biofilm-forming ability and impact on environmental bioburden in clinical laboratories

      2020, Photodiagnosis and Photodynamic Therapy
      Citation Excerpt :

      A pulsed xenon ultraviolet (PX-UV) device is a non-touch mobile medical disinfection device designed for hospital settings. It can be an effective tool to eliminate pathogens such as Clostridium difficile [8], methicillin-resistant Staphylococcus aureus [9], and vancomycin- resistant Enterococcus [10] in settings, including hospital rooms [10], operating rooms [11], surgical sites [12], breast-feeding preparation areas [13], nursing homes [14], and burn units [15]. However, to our knowledge, no studies have reported the effectiveness of PX-UV on biofilm-forming pathogens and its effectiveness at disinfecting clinical laboratories in hospitals.

    View all citing articles on Scopus
    View full text