Quality of colonoscopy withdrawal technique and variability in adenoma detection rates (with videos).

BACKGROUND: Studies suggest that endoscopist-related factors such as colonoscopy withdrawal time are important in determining the adenoma detection rate (ADR). OBJECTIVE: To determine the importance of withdrawal technique in differentiating among endoscopists with varying ADRs. DESIGN: Prospective, multicenter study. SETTING: Five academic tertiary-care medical centers. PARTICIPANTS: This study involved 11 gastroenterology faculty endoscopists. INTERVENTION: A retrospective review of screening colonoscopies was performed to categorize endoscopists into low, moderate, and high ADR groups. Video recordings were randomly obtained for each endoscopist on 20 (10 real, 10 sham) withdrawals during colonoscopies performed for average-risk colorectal cancer screening. Three blinded reviewers assigned withdrawal technique scores (total of 75 points) on 110 video recordings. A separate reviewer recorded withdrawal times. MAIN OUTCOME MEASUREMENTS: Withdrawal technique scores and withdrawal times. RESULTS: Mean (± standard deviation [SD]) withdrawal technique scores were higher in the moderate (62 ± 2.5) and high (59.5 ± 3) ADR groups compared with the low (40.8±3) ADR group (P = .002). Mean (± SD) withdrawal times were 6.3 ± 1.8 minutes (low ADR), 10.2 ± 1.5 minutes (moderate ADR), and 8.2 ± 1.8 minutes (high ADR) (P = .29). A comparison of the withdrawal times and technique scores of the two individual endoscopists with the lowest and highest ADRs did not find a significant difference in withdrawal times (6.6 ± 1.7 vs 7.4 ± 1.7 minutes) (P = .36) but did find a nearly 2-fold difference in technique scores (36.2 ± 9 vs 62.8 ± 9.9) (P = .0001). LIMITATIONS: Not adequately powered to detect small differences in withdrawal times. CONCLUSION: Withdrawal technique is an important indicator that differentiates between endoscopists with varying ADRs. It is possible that withdrawal technique is equal to, if not more important than, withdrawal time in determining ADRs.

Effects of biomaterial surface chemistry on the adhesion and biofilm formation of Staphylococcus epidermidis in vitro.

The formation of biofilm, a structured community of bacteria enclosed in slime, is a significant virulence factor in medical-device-centered infection. The development of cardiovascular device infection can be separated into two phases: initial bacterial adhesion and aggregation, followed by proliferation and production of slime. It is possible to modulate the adhesion and biofilm formation of Staphylococcus epidermidis, a commensal skin bacterium commonly found on infected medical devices, through biomaterial surface chemistry. This study examines bacterial adhesion and biofilm formation on surface-modified polyethylene terephthalate (PET), including surfaces with varying hydrophilic, hydrophobic, and ionic character. Bacterial adhesion and biofilm formation were observed over 48 hours in phosphate-buffered saline (PBS) and 20% pooled human serum. The hydrophilic surface (PAAm) had significantly less nonspecific adhesion of bacteria than that in the control (PET) and other surfaces, when cultured in PBS (P < 0.0001). Charged surfaces, both anionic and cationic, had increased adhesion and aggregation of bacteria in comparison with the control (PET) in the presence of serum proteins over 24 hours (P < 0.0001). Bacteria cultured in serum on the charged surfaces did not have significantly different amounts of biofilm formation compared with that of the control (PET) surface after 48 hours. This study showed that biomaterial surface chemistry characteristics impact initial adhesion and aggregation of S. epidermidis on biomaterials.