The Argentina Brief Colonoscopy Difficulty Score (ABCD)
Condition: Colorectal Cancer; Diagnoses Disease; Polyp of Colon; Adenoma Colon
MeSH terms: Adenoma; Colonic Polyps
Study type: Observational [Patient Registry]

Summary: 
      Colonoscopy completion by caecal intubation seldom represents a significant effort for the
      endoscopist. In this situation, additional techniques are necessary to achieve this goal:
      patients' manual abdominal compression, postural changes, and endoscopist relay. To date, no
      tool allows colonoscopy technical difficulty grading.

      This study pursues to describe the frequency of additional techniques for caecal intubation
      in a large sample of Argentinians in different centres who undergo colonoscopy for attending
      purposes, to develop a novel score for assessing colonoscopy technical difficulty.
    

Detailed description: 
      Colonoscopy is the most performed digestive endoscopy procedure worldwide. It is indicated
      for colorectal cancer screening, pre-existence surveillance, diagnostic approach in
      symptomatic patients, and therapeutic purposes. Bowel preparation is the most crucial quality
      criterion that guarantees appropriate colonic mucosa assessment. Other colonoscopy quality
      criteria included a colonoscope withdrawal time above 6 to 10 minutes and colonoscopy
      completion by caecal intubation.

      Besides bowel preparation, some situations limit caecal intubation: stenosis, diverticulitis,
      or haemodynamic instability. In the absence of one of those situations or similar, caecal
      intubation must be the goal to be achieved by every endoscopist. However, it sometimes
      represents a significant effort for the endoscopist. It can require additional techniques
      such as manual abdominal compression, postural changes, colonoscopy restart, and another
      endoscopist's new attempt. Also, this increases caecal intubation time by over 10 minutes,
      more anaesthesia and post-colonoscopy abdominal pain, with a higher risk of unnoticed
      lesions.

      To the best of our knowledge, there is no standard definition for colonoscopy technical
      difficulty in terms of caecal intubation or any tool that grades it based on previously
      mentioned additional techniques. For the moment, developed tools such as the Difficult
      Colonoscopy Score (DCS) to consider patients' pre-colonoscopy factors such as age, body mass
      index (BMI), sleep quality, and endoscopist experience. Other tools are based on a
      qualitative appreciation of the technical difficulty.

      A tool that documents those endpoints constitutes an additional objective quality criterion
      for colonic mucosa assessment, with critical change management during intra-colonoscopy and
      post-colonoscopy. Noticed a technically difficult colonoscopy deserves a more prolonged
      withdrawal time, more photo documentation, a more cautious discharge, more detailed patient
      instructions, and a personalised follow-up directed to adverse events warnings. A patient
      with a previous technically difficult colonoscopy will be planned for an earlier next
      colonoscopy, with a risk assessment independently on the age, pre-colonoscopy consulting with
      detailing of more potential adverse events, planned in a particular time and with a different
      anaesthesia planning, and even performed by a more experienced endoscopist or in a referral
      centre.

      This study pursues to describe the frequency of additional techniques for caecal intubation
      in a large sample of Argentinians in different centres who undergo colonoscopy for attending
      purposes, to develop a novel score for assessing colonoscopy technical difficulty.
    

Intervention name(s): Diagnostic high-definition white-light (HDWL) colonoscopy
Intervention type(s): Diagnostic Test
Intervention description(s): All participants will undergo to colonoscopy examination performed by competent/junior or expert/senior endoscopists (>150-400 or >400 previous colonoscopies, respectively). Bowel preparation was performed using different solutions, according to the clinical discretion of the attending, who indicated colonoscopy. After deep sedation by intravenous propofol with or without fentanyl or midazolam administration, a water-assisted colonoscopy was performed using a high-definition (HD) scope with white light (WL). Colonoscope trademark differs among participant centres.
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Patients with an indication of colonoscopy with caecal intubation, regardless of clinical
        purpose.
      
Keywords: Colonoscopy; Quality of health care; Endoscopist; Technical difficulty