The Dirty Side of Colonoscopy: Predictors of Poor Bowel Preparation and Novel Approaches to Overcome the Shortcomings

Colonoscopy significantly reduces the incidence and mortality of colorectal cancer. The quality of bowel preparation plays a direct role in the efficacy, safety, and economic burden of colonoscopy. High-quality bowel preparation is essential for meeting colorectal cancer screening goals during colonoscopy, and consideration of risk factors for inadequate cleansing can help optimize the preparation regimen. If preparation is inadequate, there are salvage methods available to improve success. A number of patient-specific factors, comorbidities, and medications can contribute to inadequate bowel preparation. Age, gender, and socioeconomic status are all associated with poor quality preparation. Comorbidities such as chronic constipation, diabetes mellitus, neurological and neuropsychiatric disorders, history of gastrointestinal surgery, and cirrhosis, as well as the use of medications such as opiates and tricyclic antidepressants can also affect preparation quality. Improvement of preparation depends on the specific factor, but can involve variation in lavage regimen, the use of adjunctive agents, and medication management. For preparation deemed inadequate during colonoscopy, there are techniques described to intra-procedurally provide more cleansing. In addition, for patients requiring same-day salvage preparation or are at high risk for poor lavage, there are two technological options that provide increased preparation quality. 106 British Journal of Gastroenterology 2019; 1(1): 106 115 . doi: 10.31488/bjg.1000103