Does use of a colonoscopy imaging device improve performance? A cohort study.

Background: Magnetic endoscopic imagers (MEIs) are being introduced during colonoscopy, principally for training. They aid recognition and resolution of loops. This has potential to improve technique resulting in increased completion rates and better patients' experience.

Objective: To determine whether the use of a MEI improves colonoscopists' performance.

Design: Cohort study.

Settings: Endoscopy unit in a district general hospital.

Patients: Consecutive patients undergoing colonoscopy during a 33 month period were studied.

Intervention: Patients underwent colonoscopy with or without the use of a magnetic endoscopic imager.

Main Outcome Measures: Patient comfort and colonoscopy completion rates with and without the use of a magnetic endoscopic imager. Other data recorded included sedation and analgesia doses, patient age and gender, bowel preparation quality, antispasmodic dose, time of day, and consciousness level.

Results: A total of 5,879 colonoscopies were performed. A magnetic endoscopic imager was used for 4,873. A greater proportion of patients in the imager group had the lowest discomfort score (56.2 vs. 39.8%, logistic regression; p = 0.005). Doses of midazolam were similar in both groups (1.93 vs. 2.14 mg for imager and nonimager groups respectively). Completion rates were 94.5% with an imager and 91% without (logistic regression; p = 0.088). Logistic regression analysis showed that buscopan improved completion rate but detrimental factors included increasing patient age, discomfort, poor bowel preparation, and an afternoon procedure. Factors not influencing completion included gender, sedation and analgesia doses, and consciousness level. There was no correlation between documented reason for failure and use of the imager.

Limitations: This was a nonrandomized trial although improved with logistic regression analysis.

Conclusions: Magnetic endoscopic imager use improves patient comfort during colonoscopy but has not been shown to improve completion.