Sedation-risk-free colonoscopy for minimizing the burden of colorectal cancer screening

Abstract

Unsedated colonoscopy is available worldwide, but is not a routine option in the United States (US). We conducted a literature review supplemented by our experience and expert commentaries to provide data to support the use of unsedated colonoscopy for colorectal cancer screening. Medline data from 1966 to 2009 were searched to identify relevant articles on the subject. Data were summarized and co-authors provided critiques as well as accounts of unsedated colonoscopy for screening and surveillance. Diagnostic colonoscopy was initially developed as an unsedated procedure. Procedure-related discomfort led to wide adoption of sedation in the US, although unsedated colonoscopy remains the usual practice elsewhere. The increased use of colonoscopy for colorectal cancer screening in healthy, asymptomatic individuals suggests a reassessment of the burden of sedation in colonoscopy for screening is appropriate in the US for lowering costs and minimizing complications for patients. A water method developed to minimize discomfort has shown promise to enhance outcomes of unsedated colonoscopy. The use of scheduled, unsedated colonoscopy in the US appears to be feasible for colorectal cancer screening. Studies to assess its applicability in diverse practice settings deserve to be conducted and supported.

DDW "Cutting Edge" Colonoscopy Techniques 2011 State-of-the-Art Lecture: Warm water infusion/CO2 insufflation for colonoscopy

“…2,3 Where it is available, conscious sedation has become standard, and even adopted for screening cases. Deep sedation enhances efficiency, but also markedly increases cost.…”

The water method significantly enhances proximal diminutive adenoma detection rate in unsedated patients

“…Previous reports of worldwide availability of unsedated colonoscopy focused discussions on cecal intubation, patient tolerance, absence of sedation side-effects and potential cost savings 37 . There is a paucity of information on ADR in unsedated patients; reported polyp detection rates ranged from 19% 38 and 20% 39 to 34% 40 .…”

The water method is effective in difficult colonoscopy—it enhances cecal intubation in unsedated patients with a history of abdominal surgery

“…Characteristics pertaining to past history included abdominal and/or pelvic surgery 8,12,30,31 , diagnosed left-sided diverticulosis 31 , incomplete colonoscopy (due to redundant colon, difficult sigmoid or difficult sedation) 32 , unsatisfactory (poor) bowel preparation 33 and irritable bowel syndrome 31 . Characteristics associated with current colonoscopy included difficult anatomy 28 , patient pain or discomfort 28,30 , symptoms of inflammatory bowel diseases 12 , prolonged insertion time (>480 sec), technically difficult insertion 12 , lower gastrointestinal bleeding 24 , obstructing malignancy 28 , severe inflammation 28 , poor bowel preparation 12,28,30 , failure to reach the cecum 34,35 , unsedated colonoscopy 3,18,21,22,36 and colonoscopy following gastroscopy 31 . Methods reported to minimize patient discomfort or enhance cecal intubation during colonoscopy were reviewed 37 and included the use of pediatric colonoscope, variable stiffness colonoscope, gastroscope, computer assisted colonoscope, magnetic endoscope imaging, hypnosis, patient inhalation of nitrous oxide, listening to music, distraction by audio stimuli, or simply allowing the patients to participate in administration of the sedation medication.…”