Recommendations to Resolve Inconsistent Guidelines for the Reprocessing of Sheathed and Unsheathed Rigid Laryngoscopes
Neither a consensus statement nor a formal set of step‐by‐step guidelines for reprocessing rigid laryngoscopes have been published or endorsed by professional organizations. Several published guidelines, standards, and clinical reports were reviewed to evaluate the risk of nosocomial infection associated with the use of rigid laryngoscopes, to determine their minimum reprocessing requirements. This review found that the recommendations of some guidelines and standards for reprocessing rigid laryngoscopes are incomplete, inadequate, and inconsistent with one another, and that current practices for reprocessing rigid laryngoscopes are reported to be inadequate and lack standardization. It is recommended that a consensus statement be developed that standardizes the reprocessing of rigid laryngoscopes and requires cleaning followed by high‐level disinfection (or sterilization) and drying of the rigid laryngoscope’s blade and handle to prevent nosocomial infection, regardless of whether a protective barrier or sheath is used during the procedure.
Received April 10, 2006; accepted July 10, 2006; electronically published March 9, 2007.
Rigid laryngoscopes have many clinical applications and are routinely used to examine the larynx and vocal cords and for airway management. This transportable instrument features a detachable and reusable or disposable (single‐use) folding fiber‐optic blade that connects to a durable, reusable handle, which usually contains a battery that powers the laryngoscope’s light source. Neither a consensus statement nor a formal set of step‐by‐step guidelines for reprocessing rigid laryngoscopes has been published or endorsed by professional organizations. Several published guidelines, standards, and clinical reports were reviewed to evaluate the risk of nosocomial infection associated with the use of rigid laryngoscopes, with the intention of determining their minimum reprocessing requirements.1‐7 These guidelines and standards were also reviewed and compared, to evaluate the completeness and adequacy of their respective recommendations and their consistency with one another. This review found that some guidelines and standards for reprocessing rigid laryngoscopes are incomplete, inadequate, and inconsistent with one another. For instance, one guideline recommends that the handle of the laryngoscope be low‐level disinfected, whereas others recommend that it be high‐level disinfected or sterilized to prevent disease transmission. This review also found that, like these guidelines and standards, current practices for reprocessing rigid laryngoscopes are reported to be inadequate and lack standardization, varying significantly from one healthcare facility to another.7‐9 Variations and inconsistencies in reprocessing guidelines and practices can result in ineffective reprocessing, confusion among healthcare staff members, an inconsistent and inadequate standard of care, and an increased risk of patient‐to‐patient disease transmission.4,6,8 These variations and inconsistencies may have contributed to inadequate reprocessing of rigid laryngoscopes that resulted in a recent outbreak of Pseudomonas aeruginosa with associated patient injuries and deaths in a medical center's neonatal and pediatric intensive care units.10
Spaulding’s Classification Scheme
The level of disinfection or sterilization necessary to prevent a medical device from transmitting disease is typically determined using a classification scheme developed by Spaulding.11 This scheme classifies medical devices on the basis of the risk of disease transmission and nosocomial infection associated with their clinical use. According to this scheme, medical devices that directly or indirectly contact mucous membranes or nonintact skin, without ordinarily entering sterile tissue or the vasculature, are classified as semicritical devices, for which this scheme prescribes high‐level disinfection (or sterilization). The rigid laryngoscope’s blade and handle may become contaminated with blood, patient debris, secretions, and potentially pathogenic microorganisms during airway management and other clinical applications.2,4‐7,9 Proper reprocessing of both the blade and the handle is essential to prevent disease transmission. In accordance with Spaulding’s scheme, the American Association of Nurse Anesthetists, the Association for Professionals in Infection Control and Epidemiology, the Centers for Disease Control and Prevention (CDC), and the Food and Drug Administration (FDA) classify the laryngoscope’s blade and handle as semicritical devices, for which these organizations recommend high‐level disinfection (or sterilization), because both the blade and the handle directly or indirectly contact mucous membranes or nonintact skin of the oral cavity, throat, and neck during rigid laryngoscopy.2,3,12‐14 An example of contamination of the laryngoscope by indirect contact with mucous membranes would be the soiling of the handle with patient debris during the folding of a contaminated blade onto the handle after a procedure, such as endotracheal intubation, or during improper handling of the blade or handle with dirty hands or gloves.5‐7
Although acknowledging and agreeing with these organizations that the laryngoscope’s blade is a semicritical device for which high‐level disinfection (or sterilization) is recommended, guidelines published by the Association of Perioperative Registered Nurses (AORN), however, classify the laryngoscope’s handle, to which the blade directly attaches, as a noncritical device, for which AORN guidelines recommend low‐level disinfection.1 (The AORN guideline references only a study coauthored by Phillips and Monaghan4 as providing the scientific basis and rationale for the recommendation of low‐level disinfection of the laryngoscope's handle, even though this study, ironically and properly, recommends instead high‐level disinfection or sterilization of the handle as well as of the blade to prevent disease transmission.) AORN guidelines view the laryngoscope’s blade and handle as two independent and separate reusable components, each associated with a different risk of disease transmission. These guidelines, which recommend high‐level disinfection for the blade but low‐level disinfection for the handle, are confusing and inconsistent with other guidelines that view the laryngoscope as a single instrument, classifying its blade and handle as semicritical devices and recommending high‐level disinfection for both.2,3,12‐14 Like a dental handpiece, the rigid laryngoscope has a handle and other surfaces that can become contaminated with potentially infectious materials during clinical use but that do not necessarily come in direct contact with mucous membranes.2,3,12‐14
The proverbial chain is only as strong as its weakest link. As a consequence of their direct physical contact with one another during clinical use, connection of a low‐level disinfected handle to a high‐level disinfected blade may result in recontamination of the blade, effectively compromising its integrity and reducing its level of decontamination to low‐level disinfection. Whereas high‐level disinfection destroys vegetative bacteria, mycobacteria (including the causative agent of tuberculosis), fungi, viruses, and some bacterial endospores,1 low‐level disinfection is neither tuberculocidal nor sporicidal. As a consequence, microorganisms, including mycobacteria, that may have contaminated the handle during rigid laryngoscopy and survived the cleaning and low‐level disinfection may recontaminate the blade to which the handle is directly connected and be transmitted to the patient (ie, patient‐to‐patient disease transmission) during rigid laryngoscopy. To be sure, low‐level disinfection of the laryngoscope’s blade (or handle and other semicritical devices) is inadequate and poses an increased risk of nosocomial infection.2‐7,9 Low‐level disinfection (and intermediate‐level disinfection) is restricted to the reprocessing of a noncritical medical device, such as a blood pressure cuff, a stethoscope, or an oximeter probe.
Sheaths and Protective Barriers
Because of concern about the risk of contamination and disease transmission during rigid laryngoscopy, some healthcare facilities may use a single‐use (disposable) sterile sheath or protective barrier to cover the laryngoscope’s blade, handle, or both.12,15 But clinical use of this sheath warrants clarification and caution. According to an FDA guidance document, use of a sheath to cover the laryngoscope does not eliminate reprocessing of its blade or handle,12 because either may become contaminated with potentially infectious materials during application or removal of the sheath before or after the procedure, respectively, posing an increased risk of nosocomial infection. Nevertheless, according to this FDA guidance document, if the manufacturer has demonstrated that the sheath will provide a sufficiently protective barrier to prevent breakage and contamination of the covered laryngoscope, then the FDA may conclude that reprocessing the laryngoscope after removal of the sheath can be expedited and that cleaning followed by intermediate‐level disinfection—achieved by, for example, wiping of the laryngoscope’s blade and handle with a gauze pad soaked with 70% isopropyl alcohol—is adequate to prevent disease transmission.12 However, intermediate‐level disinfection, although tuberculocidal, is not sporicidal. Clostridium difficile is a spore‐forming bacterium that has been identified in the clinical setting, and, although it is destroyed by high‐level disinfection and sterilization, this potentially pathogenic microorganism, like other sporulated bacteria, is not destroyed by intermediate‐level or low‐level disinfection.
The recommendation to use intermediate‐level disinfection for a laryngoscope in lieu of high‐level disinfection (or sterilization) after removal of the sheath,12 although also in agreement with the CDC’s guideline for the reprocessing of some types of barrier‐protected devices used in dentistry,13 is confusing, arguably inadequate, and inconsistent with the Spaulding scheme, which recommends high‐level disinfection (or sterilization) for laryngoscopes and other semicritical devices.2,3,12‐14 Although use of a sheath would be expected to minimize the likelihood of contamination of the covered instrument during clinical use, it is possible—regardless of whether published data demonstrating the sheath’s protective properties were submitted to and reviewed by the FDA—that the sheath may fail or its integrity may become breached,15 resulting in contamination of the “protected” instrument with pathogens, such as C. difficile, that have clinical significance and are not destroyed by merely a wiping of the instrument’s surfaces with a gauze pad soaked with 70% isopropyl alcohol, requiring instead high‐level disinfection (or sterilization) for their destruction. Furthermore, as the FDA acknowledges,12 the laryngoscope may become contaminated during improper handling or during application or removal of the sheath and may transmit infectious materials, including methicillin‐resistant Staphylococcus aureus, to the patient.5‐7,9 As a consequence, the FDA’s recommendation of intermediate‐level disinfection, instead of high‐level disinfection (or sterilization), of a laryngoscope that was covered with a sheath during the procedure would appear to be inadequate.2,3,5,12‐14
Recommendations
The following recommendations are provided for completeness and to resolve the inadequacies, inconsistencies, and confusion provided by some published guidelines and standards for reprocessing of the blades and handles of rigid laryngoscopes; to standardize reprocessing practices; to eliminate variations in the standard of care; and to prevent disease transmission and nosocomial infection.
| I. | Recommendations for professional organizations and federal regulatory agencies are as follows.
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| II. | Recommendations for healthcare professionals are as follows.
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| III. | Recommendations for manufacturers are as follows.
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References
- 1. Association of periOperative Registered Nurses. Recommended practices for cleaning, handling, and processing anesthesia equipment. AORN J 2005; 81:856‐870.
- 2. American Association of Nurse Anesthetists (AANA). Infection Control Guide, Revised. Park Ridge, IL: AANA; 1997:13‐23. Available at: http://www.aana.com/Resources.aspx?ucNavMenu_TSMenuTargetID=51&ucNavMenu_TSMenuTargetType=4&ucNavMenu_TSMenuID=6&id=737. Accessed April 4, 2006.
- 3. Alvarado CJ, Reichelderfer M. APIC guidelines for infection prevention and control in flexible endoscopy. Association for Professionals in Infection Control. Am J Infect Control 2000; 28:138‐155.
- 4. Phillips RA, Monaghan WP. Incidence of visible and occult blood on laryngoscope blades and handles. AANA J 1997; 65:241‐246.
- 5. Simmons SA. Laryngoscope handles: a potential for infection. AANA J 2000; 68:233‐236.
- 6. Yee KF. Decontamination issues and perceived reliability of the laryngoscope—a clinician’s perspective. Anaesth Intensive Care 2003; 31:658‐662.
- 7. Esler MD, Baines LC, Wilkinson DJ, et al. Decontamination of laryngoscopes: a survey of national practice. Anaesthesia 1999; 54:587‐592.
- 8. Banfield GK, Hinton AE. A national survey of disinfection techniques for flexible nasoendoscopes in UK ENT out‐patient departments. J Laryngol Otol 2000; 114:202‐204.
- 9. Beamer JER. MRSA contamination of a laryngoscope blade: a potential vector for cross infection. Anaesthesia 1999; 54:1010‐1011.
- 10. White Memorial Medical Center Statement. Bacteria outbreak closes baby and children units in LA hospital. 2006. Available at: http://www.healthnews‐stat.com/?id+281&keys+Outbreak‐childrens‐hospit‐White‐Memorial‐Hospital‐closed‐hospital. Accessed February 28, 2007.
- 11. Spaulding EH. Chemical disinfection of medical and surgical materials. In: Lawrence CA, Block SS, eds. Disinfection, Sterilization and Preservation. Philadephia, PA: Lea & Febiger; 1968:517‐531.
- 12. Food and Drug Administration. Guidance for Manufacturers Seeking Marketing Clearance of Ear, Nose, and Throat Endoscope Sheaths Used as Protective Barriers. Washington, DC: Department of Health and Human Services; 2000. Available at: http://www.fda.gov/cdrh/ode/guidance/954.html. Accessed February 28, 2007.
- 13. Centers for Disease Control and Prevention. Guidelines for infection control in dental health care settings, 2003. MMWR Recomm Rep 2003; 52(RR‐17):1‐61. Available at: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5217a1.htm. Accessed April 4, 2006.
- 14. Centers for Disease Control and Prevention. Guidelines for prevention of nosocomial pneumonia. MMWR Morb Mortal Wkly Rep 1997; 46(RR‐1):1‐79. Available at: http://www.cdc.gov/mmwr/preview/mmwrhtml/00045365.htm. Accessed October 5, 2004.
- 15. Chen YH, Wong KL, Shieh JP, et al. Use of condoms as blade covers during laryngoscopy, a method to reduce possible cross infection among patients. J Infect 2006; 52:118‐123.
- 16. Food and Drug Administration. FDA Public Health Notification: Reprocessing of Reusable Ultrasound Transducer Assemblies Used for Biopsy Procedures. Washington, DC: Department of Health and Human Services; 2006. Available at: http://www.fda.gov/cdrh/safety/061906‐ultrasoundtransducers.html. Accessed February 28, 2007.