Introduction Colonoscopy is the gold standard investigation for colonic assessment. To maintain clinical excellence in colonoscopy several performance indicators are recognised.¹ Colonic looping is a common patient-related factor which may reduce completion rates. The magnetic endoscope imager (MEI), a device which generates a three-dimensional map of colonoscope orientation, provides feedback regarding tip location and loop formation. MEI may improve colonoscopy outcomes however findings are inconsistent. This study aimed to evaluate whether MEI use improves outcomes in colonoscopy completed by a single endoscopist.

Methods This retrospective cohort study investigated the effect of MEI on procedure completion, polyp detection, medication doses (sedation, analgesia and buscopan), endoscopist and nurse discomfort scores and patient satisfaction in patients undergoing colonoscopy. Data was obtained by interrogation of electronic colonoscopy records for a single gastroenterologist between December 2009 and November 2014. The equipment used for all colonoscopies was identical in make and age, the only difference being the presence or absence of the MEI. Statistical analysis was completed using Wizard©.

Results 2129 colonoscopies were completed during the study period across three endoscopy units. After exclusion of incomplete data, study groups significantly differed by age demographics. By excluding patients older than 74 y, study groups (n = 914 without MEI, n = 359 with MEI) had similar age (p = 0.06) and gender (p = 0.962) characteristics. MEI use did not significantly influence colonoscopy completion (97.2% vs 96.3%, (p = 0.412)) or polyp detection (24.8% vs 29.1%, (p = 0.132)). Colonoscopies completed without MEI were associated with higher doses of midazolam (1.618 mg ± 0.051 vs 1.379 mg ± 0.097, p < 0.001), fentanyl (1.313 μg ± 0.557 vs 0.348 0μg ± 0.493, p = 0.044), pethidine (24.858 mg ± 0.986 vs 23.259 mg ± 1.784, p = 0.104) and buscopan (16.247 mg ± 0.526 vs 13.510 mg ± 1.041, p < 0.001). Comfort scores and patient satisfaction outcomes were sub-analysed in colonoscopies completed without analgesia or sedation (n = 244). MEI use did not significantly affect endoscopist (p = 0.383) or nurse discomfort scores (p = 0.383 and p = 0.971) or patient satisfaction ratings (p = 0.209).

Conclusion Real world use of MEI at colonoscopy did not improve polyp detection or completion rates but was associated with decreased analgesia, sedation and buscopan use. Unsedated colonoscopy was associated with similar comfort and satisfaction scores regardless of MEI use. Endoscopists may anticipate greater discomfort without MEI and overcompensate sedation doses. Medication dosing should remain consistent regardless of MEI availability.

Reference 1 BSG quality and safety indicators for endoscopy. JAG advisory group on GI endoscopy. March 2007.

Disclosure of Interest None Declared