Towards Painless Colonoscopy: a Dedicated Training to Decrease the Rate of Painful Colonoscopy - a Randomized Controlled Trial

Background and study rationale:

Colorectal cancer (CRC) is the second leading cause of death from cancer in Europe. Several modalities of CRC screening exist, with each screening modality including colonoscopy either as a primary or secondary test (following positive sigmoidoscopy or faecal occult blood test). Unfortunately, patients perceive colonoscopy as a painful and unpleasant procedure. This is one of the major barriers for participation in CRC screening, particularly since those being screened are usually healthy and asymptomatic. Monitoring patient-reported outcomes is one of the understudied performance measures for quality in colonoscopy according to recent guidelines.

Since 2014, the Polish Colorectal Cancer Screening Programme (PCSP) has routinely used the Gastronet questionnaire to measure patient-reported outcomes. The Gastronet is a Norwegian quality-assurance programme that was initiated in 2003. Patients fill in the questionnaire at home 1 day after colonoscopy and send it back via traditional mail. Questions on pain are answered on a 4-point scale: no pain, slight pain, moderate pain, and severe pain. This scale has been validated previously.

In previous analysis, the investigators have identified several, independent risk factors for painful colonoscopy. However, the single, most important risk factor for painful colonoscopy was the endoscopist himself. This was shown with regards to pain rates adjusted for all factors found relevant in multivariate models (including sedation). The variation among endoscopists was observed as 11- to 23-fold difference in adjusted painful colonoscopy rate. Adjusting for most measurable variables allowed us to cancel the effect of patient selection or other technical issues (endoscope used etc.) and attribute the observed differences, with high probability, to the individual, unquantifiable technical and nontechnical skills possessed by each endoscopist. These skills comprise both the interpersonal skills required to establish a meaningful patient-endoscopist relationship and individual manual skills.

Among modifiable factors, propofol sedation resulted in better procedure tolerance. In most countries, the propofol sedation must be performed by an anaesthesiologist. This practice generates higher costs and reduces colonoscopy unit capacity, as it requires more time, resources, and personnel. Moreover, sedated colonoscopy poses a greater risk of sedation-related (e.g., pneumonia and cardiovascular events) and procedure-related (e.g., bowel perforation and bleeding) complications. What was surprising, sedation based on combination of opioids and benzodiazepines (regarded devoid of aforementioned downsides of propofol sedation) did not improve colonoscopy tolerance in comparison to no sedation at all. This observation led us to suggesting that only propofol sedation should be regarded as effective in case of colonoscopy.