Is Alcohol Swabbing Sufficient to Clean Otoscopes in Hospitals?

다국어 초록 (Multilingual Abstract)

Background and Objectives An otoscope is a basic instrument used by otorhinolaryngologists. An inappropriately sterilized otoscope has been reported to be a possible bacterial vector for infection. In this regard, we decided to investigate contaminated otoscopes for possible bacterial contamination and evaluate the efficacy of the otoscope disinfection methods.
Materials and Method We randomly drew 22 otoscope cones from university hospitals and 10 from private hospitals. Cones were divided into three groups accordingly to their sterilization methods: group 1 was wiped with 70% isopropyl alcohol, group 2 was soaked for 20 min in 70% isopropyl alcohol, and group 3 was soaked in CIDEX solution. The samples were cultured twice, first before the disinfection process and then after the disinfection process. Otoscopes were cleaned for a week by employing these techniques.
Results Most of the pre-sterilized otoscopes (20/22) were obtained from the hospitals which demonstrated contamination with microorganisms. Staphylococcus was the most common bacteria found (16/22). After a week of cleansing, no bacteria were seen in group 1 (0%, 0/8), whereas group 2 (14.3%, 1/7), and group 3 (28.6%, 2/7) still showed remaining microorganisms. The three methods were significantly effective on sterilizing microorganisms.
Conclusion An otoscope can be a vector for spreading infection. We found that disinfection by alcohol-swabbing alone is sufficient for sterilizing otoscope cones. Clinically, this information may be useful to otorhinolaryngologists. However, further studies are required to establish the most appropriate disinfection protocol to prevent infection from microorganisms.
Korean J Otorhinolaryngol-Head Neck Surg 2016;59(8):578-82

참고문헌 (Reference)

1 Cohen HA, "Stethoscopes and otoscopes--a potential vector of infection?" 14 (14): 446-449, 1997

2 Yun HJ, "Prevalence and mechanisms of low- and high-level mupirocin resistance in staphylococci isolated from a Korean Hospital" 51 (51): 619-623, 2003

3 Cockerill FR, "Performance standards for antimicrobial susceptibility testing: twenty-first informational supplement"

4 Bou R, "Nosocomial outbreak of Pseudomonas aeruginosa infections related to a flexible bronchoscope" 64 (64): 129-135, 2006

5 Winn Jr W, "Koneman’s color atlas and textbook of diagnostic microbiology" Lippincott Williams & Wilkins 1156-1166, 2006

6 Doroghazi RM, "Invasive external otitis. Report of 21 cases and review of the literature" 71 (71): 603-614, 1981

7 Rutala WA, "Guideline for disinfection and sterilization in healthcare facilities, 2008" Centers for Disease Control 2008

8 Benson WG, "Exposure to glutaraldehyde" 34 (34): 63-64, 1984

9 Newton HM, "Evaluation of otoscope cone cleaning and disinfection procedures commonly used in veterinary medical practices: a pilot study" 17 (17): 147-150, 2006

10 Bluestone CD, "Epidemiology and pathogenesis of chronic suppurative otitis media: implications for prevention and treatment" 42 (42): 207-223, 1998

11 Spaulding E, "Disinfection, sterilization, and preservation" Lea &Febiger 517-531, 1968

12 Burco A, "Current infection control trends in audiology. Independent studies and capstones, Program in Audiology and Communication Sciences" Washington University School of Medicine 2007

13 Korkmaz H, "Cross-contamination and cross-infection risk of otoscope heads" 270 (270): 3183-3186, 2013

14 Vandepitte J, "Basic laboratory procedures in clinical bacteriology" World Health Organization 32-33, 2003

15 Forbes BA, "Bailey & Scott’s diagnostic microbiology" Mosby 933-934, 2002

16 Iversen BG, "An outbreak of Pseudomonas aeruginosa infection caused by contaminated mouth swabs" 44 (44): 794-801, 2007