|MadSci Network: Medicine|
Flexible laryngoscopes are one of the most commonly used tools in the Otolaryngologist's office. Because they contact mucous membranes, but do not enter sterile sites, current recommendations are that they receive High Level Disinfection between patient use. This is not technically sterilization, since it only destroys a limited number of bacterial spores.
Because the risk of infection transmission by flexible laryngoscopes is low, High Level Disinfection is considered the standard of care. High pressure steam is the gold standard by which most other sterilization and disinfections methods are measured. Unfortunately, the optics, plastics, and articulating mechanisms in flexible scopes are quickly degraded by heat sterilization.
However, there are several methods to achieve High Level Disinfection. One of the most widely used is to place sterile disposable sheath over the scope before each use. This has advantages of being sterile, convenient, and having a rapid turn over time. Disadvantages are cost ($5-20 per sheath), increased scope size, and decreased image quality. Another widely use method is soaking the instrument in a disinfectant solution (like scissors at the barbershop). This requires between 5 and 20 minutes depending on the solution and if an automated reprocessor is used to maintain an elevated temperature and/or pressure. A recently reported method is the use of a disinfectant wipe, with a tradename of Tristel.
This does not appear to be approved for use in the US, but seems to be gaining use in the UK.
Personally, I would prefer to be the first patient in the morning (after the scopes have soaked overnight) and have the procedure done without a sheath. But if I'm in the ER, I would rather have a sheath since who knows when that scope was last cleaned.
For those interested in further reading, the following sites were useful:
Infection Control Today - good summary of levels of disinfection http://www.infectioncontroltoday.com/articles/551cover.html
Cidex - disinfectant solution http://www.sterrad.com/products_&_services/cidex/CIDEX_OPA/index.asp
Tristel - Disinfectant wipe system http://www.tristel.com/ent.html
Scary article on why you want a sheath on that scope in the ER:
J. Kanagalingam, A. Zainal, C. Georgalas, S. Paun, and N. S. Tolley (2002)
The disinfection of flexible fibre-optic nasendoscopes out-of-hours: confidential telephone survey of ENT units in England.
The Journal of Laryngology & Otology. 116: 817-822.
( http://journals.cambridge.org/action/displayAbstract;jsessionid=925B0077B7BEF5517592F6AB3CF1C 72A.tomcat1?fromPage=online&aid=402661)
Try the links in the MadSci Library for more information on Medicine.