Efficiency of the Glutaraldehyde Test Strip for Monitor ing the Concentration of Glutaraldehyde in Reused Solu tions for Disinfecting Endoscopes
ANUWAT KEERASUNTONPONG, M.D.*, PRA TYA SITA POSA, M.D.*, ANGKANA CHAIPRASERT, Dr.rer.nat.**, VISANU THAMLIKITKUL, M.D.*
Affiliation : * Department of Medicine, **Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
Objective : To determine the efficiency of a glutaraldehyde test strip (GTS) in monitoring the amount of glutaraldehyde in a reused solution for disinfecting endoscopes.
Method : Reused glutaraldehyde solutions for disinfecting bronchoscopes, gastroscopes and colonoscopes were tested for the concentration of glutaraldehyde with a GTS thrice weekly for the first week and then every working day up to 56 days. If the GTS indicated a concentration of glutaral dehyde;;:: 1.8 per cent after 21 days, 5 ml of the solution was taken to the laboratory to determine its mycobactericidal activity.
Results : All samples of the reused glutaraldehyde solution up to 56 days with a concentra tion of;;:: 1.8 per cent glutaraldehyde on GTS from testings showed mycobactericidal activity. If the glutaraldehyde solution was reused for up to 28, 42 or 56 days, it could save 9,603; 22,813 and 29,415 baht per year respectively for the gastroscopy and colonoscopy units. The corresponding figures were -949; 2, 726 and 4,564 baht per year for the bronchoscopy unit. It is estimated that up to 400,000 baht per year could be saved by adopting the strategy of GTS monitoring in all endoscopy units at Siriraj Hospital.
Conclusion : The current strategy of discarding reused glutaraldehyde solution in the gastro scopy, colonoscopy and bronchoscopy units at Siriraj Hospital may be inappropriate since the reused solution is still mycobactericidal for up to 56 days.
Keywords : Glutaraldehyde, Glutaraldehyde Test Strip, Endoscopes
