Results of gastroscope bacterial decontamination by enzymatic detergent compared to chlorhexidine

Table 1 Steps for gastroscope reprocessing in the present study

Gastroscope reprocessing
Cleaning After completion of the cleaning procedure, the inserted tube was wiped with a wet cloth and soaked in detergent solution (chlorhexidine or 3E-ZYME). Detergent solution was suctioned through the biopsy channel until the solution was visibly clean.
While the scope was submerged, mechanical cleaning was performed by washing all debris from the exterior. All removable parts were separately cleaned. A soft cleaning brush was used to clean all accessible channels. Manual cleansing was done for 10 min.
The scope was removed from the detergent solution and then submerged in 5 L of filtered water. An all-channel irrigator was used to flush water through it.
Leak testing of the scope was performed.
Disinfection After manual cleaning, the gastroscope underwent high-level disinfection in a container using 2% glutaraldehyde with a 20-min soak time.
The scope was removed from 2% glutaraldehyde and then submerged in 5 L of filtered water. An all-channel irrigator was used to flush water through it.
Rinsing and Drying The suction/biopsy channel was rinsed with 70% alcohol 20 mL and dried for 5 min.
The suction/biopsy channel was sampled using the flush method.

Table 2 Characteristics of endoscopes in both groups

	Enzymatic detergent	Chlorhexidine
Specimen (n)	130	130
Endoscopes
Olympus GIF-V	30	30
Olympus GIF-IT 140	30	30
Pentax 2970 K	35	35
Pentax 2930 K	22	22
Pentax 3830 TK	13	13

Table 3 Results of bacterial contamination after gastroscope reprocessing in both groups

	Enzymaticdetergent(n = 130)	Chlorhexidine(n = 130)	P
Type of endoscope (Olympus:Pentax)	60:70	60:70
Positive culture (> 200 cfu/mL)	6 (4.6%)	4 (3.1%)	0.747a
Single organism	5 (3.8%)	1 (0.8%)	0.213b
Mixed organism	1 (0.8%)	3 (2.3%)	0.622b
Pseudomonas aeruginosa	4 (3.1%)	5 (3.8%)	1.000b
Non Pseudomonas spp.	3 (2.3%)	3 (2.3%)	1.000b

a: chi square test; b: Fisher’s exact test.

Table 4 Incidence and types of organisms during study period

Type of organism	Enzymaticdetergent(samples, n)	Chlorhexidine(samples, n)	Total,n (%)
Pseudomonas aeruginosa	4	5	9 (60)
Klebsiella species	1	1	2 (13.3)
Enterobacter species	1	0	1 (6.7)
Acinetobacter baumanii	0	1	1 (6.7)
Staphylococcus coagulase negative	1	0	1 (6.7)
Staphylococcus aureus	0	1	1 (6.7)
Total	7	8	15 (100)