Covering the biopsy hole check valve with “enzymolysis gauze” reduces bacterial contamination in the endoscopy room

Figure 1 Schematic for air collection. A: Endoscopic procedures; B: Enzymolysis gauze; C: Anderson six-stage impact microorganism sampler diagram. The device operates by directing air through a perforated screen plate to an agar plate.

Figure 2 Quantification of airborne bacterial load. A: Covering the biopsy hole check valve with enzymolysis gauze significantly reduced Gram-positive bacterial load near the endoscopist; B and C: In the control (B) and experimental (C) groups, bacterial load during insertion was higher than during withdrawal; D and E: Comparison of bacterial loads between the two groups during insertion (D) and withdrawal (E); F: Bacterial load (colony-forming unit/m³) before, during, and after a daily colonoscopy schedule; G: Bioaerosol accumulation during a representative endoscopy day. Lower aerosol levels were observed in the enzymolysis gauze group. CFU: Colony-forming unit.

Figure 3 Correlation between intestinal cleanliness and bacterial load. A: Control group; B: Experimental group. CFU: Colony-forming unit; BBPS: Boston Bowel Preparation Scale.

Figure 4 Proportion of bacterial species identified. A: Top four bacterial species in the control group; B: Top four bacterial species in the experimental group.