partial obstruction caused by fixed or inflammatory strictures, delayed gastric emptying (medication or disease-related), hospitalization status, and urgency BTK inhibitor solubility dmso of the examination may all affect the bowel preparation regimen, including the choice of purgative, and the frequency, rate, and mode of purgative delivery. Concern for partial or high-grade obstruction may favor the use of small-volume, oral solutions supplemented by intravenous hydration or the use of a slow oral trickle preparation delivered over longer periods rather than more rapid administration of large-volume solutions. Furthermore, use of split-dosing regimens (which include same-day purgative administration 4–6 hours before endoscopy) may be contraindicated in the setting of mechanically delayed intestinal transit because Selleckchem ZD1839 of higher aspiration risk. Patients with severe active colitis and diarrhea may require only minimal laxative administration to achieve adequate preparation for disease staging because of rapid transit, the absence of solid fecal matter, and decreased adherence of liquid stool to the intestinal wall. British National Health Service guidelines33 designate
severe acute active inflammation as an absolute contraindication to oral preparation administration. Thus, in patients with active disease, safety factors and disease-related symptoms make a pristine colon a less rigid goal of bowel preparation. In contrast, a meticulous bowel preparation is important in patients undergoing routine, elective colonoscopy for dysplasia surveillance. Farnesyltransferase Whenever possible, the disease should be in remission at the time of surveillance colonoscopy, because active inflammation interferes with visual detection of nonpolypoid dysplasia and causes cytologic changes, which can be difficult to distinguish from true dysplasia. Complications of active inflammation therefore are of lesser concern, and preparation decisions
focus on achieving maximum bowel cleanliness. The best preparation regimen consists of an appropriate preprocedure diet, a suitable choice of laxative agent, and an optimal dosing of laxative administration. It is vitally important that physicians and nursing staff educate patients about the importance of the bowel preparation, carefully reviewing recommended dietary restrictions and counseling strict adherence to bowel preparation instructions. The remainder of this article emphasizes recommended, established preparation techniques for the purpose of nonurgent surveillance in patients with controlled disease. There are several uncertainties regarding the best preprocedure diet.