Flexible nasoendoscopy decontamination: a comparison between Rapicide and Tristel wipes, a prospective cohort study

Yijin Jereme Gan, Alex Mathews, Phua Chuqin, Ivan Khoo, David Loke


Background: The current disinfection of nasoendoscopes in our clinic setting is a 3-step process involving Rapicide, a peracetic acid based disinfectant. Our study aimed to validate the efficacy of Tristel wipes, a chlorine dioxide based disinfectant, as a comparable alternative.

Methods: We recruited a hundred volunteers undergoing routine flexible nasoendoscopic examinations in a general ENT. We used two separate endoscopes for each examination, following which a microbiological swab was sent from the tip of each nasoendoscope. The two nasoendoscopes were then subjected to a similar 3-step decontamination process except for the second step, where they were disinfected either tristel wipes or rapicide disinfectant. After decontamination, we took a second swab from the tip of each nasoendoscope.  

Results: Out of 200 swabs from the tip of the nasoendoscopes prior to decontamination, there were 82 positive cultures for the Rapicide cohort and 76 positive cultures for the Tristel wipes cohort. Regarding the post decontamination results, there were four positive swab cultures for those disinfected with Tristel wipes and one positive swab culture for the Rapicide cohort. These were analyzed by the Z score and there was no statistical difference between either the pre-decontamination swabs or the post decontaminations swabs with the p-values at p=0.298 and p=0.174 respectively. The efficacy of decontamination for the Rapicide solution was 98.8% compared to 94.7% for the Tristel wipes with p=0.147.

Conclusions:This study validates the efficacy of Tristel wipes as a comparable alternative to peracetic acid based disinfectants for disinfection of flexible nasoendoscopes.



Nasoendoscope, Decontamination, Tristel wipes, Peracetic acid, Rapicide

Full Text:



Muscarella LF. Prevention of disease transmission during flexible laryngoscopy. Am J Infect Control. 2007;45:536–44.

Spaulding EH. Chemical disinfection and antisepsis in the hospital. J Hosp Res. 1957;9:5–31.

Collins WO. A review of reprocessing techniques of flexible nasopharyngoscopes. Otolaryngol Head Neck Surg. 2009;141:307–10.

Jones PH, Malik T, Ridgway G, Bates G. Guidelines for Cleaning Fibreoptic. Laryngoscopes. London: ENT UK; 2005.

Niven K. An Evaluation of Chemical Disinfecting Agents Used in Endoscopy Suites in the NHS. London: HSE; 2006.

Tzanidakis K, Choudhury N, Bhat S, Weerasinghe A, Marais J. Evaluation of disinfection of flexible nasendoscopes using Tristel wipes: a prospective single blind study. Ann R Coll Surg Engl. 2012;94:185–8.

Tristel Factsheet. 2010 Available at: http://www. Accessed on 12th March 2016.

Jousimies-Somer HR, Savolainen S, Ylikoski JS. Comparison of nasal bacterial floras in two groups of healthy subjects and in patients with acute maxillary sinusitis. J Clin Microbiol. 1989;27:2736–43.

American Society for Gastrointestinal Endoscopy Ad Hoc Committee on Disinfection. Reprocessing of flexible gastrointestinal endoscopes. Gastrointest Endosc. 1996;43:540-6

Cavaliere M, Iemma M. Guidelines for Reprocessing Nonlumened Heat-Sensitive Ear/ Nose/Throat Endoscopes. Laryngoscope. 2012;122:1708-18.

Rapicide PA High Level Disinfectant. Available at: minntech/documents/50096-959%20REV%20D.pdf Accessed on 12th March 2016.

Battacharyya N, Kepnes LJ. The effectiveness of immersion disinfection for flexible fiberoptic laryngoscopes. Otolaryngol Head Neck Surg. 2004;130:681–5.

Phua CQ, Mahalingappa Y, Karagama Y. Sequential cohort study comparing chlorine dioxide wipes with automated washing for decontamination of flexible nasoendoscopes. J Laryngol Otol. 2012;126:809–14.

Ministry of Health Singapore. Stop TB in My Lifetime. World TB Day Press Release. 23 March 2012. Available at: content/moh_web/home/pressRoom/pressRoomItemRelease/2012/stop_TB_in_my_lifetime.html. Accessed on 12th March 2016

Hitchcock B, Moynan S, Frampton C, Reuther R, Gilling P and Rowe F. A randomised, single-blind comparison of high-level disinfectants for flexible nasoendoscopes. J Laryngol Otol. 2016;130(11):983-9.