Adequate bowel preparation is important for successful colonoscopic examination. Several effective colonic cleansing agents are available and routinely prescribed, but each carries its own limitations and benefits fro...Adequate bowel preparation is important for successful colonoscopic examination. Several effective colonic cleansing agents are available and routinely prescribed, but each carries its own limitations and benefits from particular dosing regimens. The most frequently prescribed colonic cleansing agent, the polyethylene glycol (PEG) cathartic solution, suffers from low patient compliance in general, due to its unpalatable taste and smell coupled with the large ingested volumes required. However, PEG is preferred over other cathartics for use in individuals of advanced age, sufferers of chronic kidney disease, heart failure and inflammatory bowel disease, and women who are pregnant or lactating. The laxative agents sodium phosphate (NaP) and sodium picosulfate plus magnesium citrate have been applied and have improved patient compliance and tolerance. NaP, however, should be avoided in individuals with impaired renal function or plasma clearance, such as those with chronic kidney disease, who are taking drugs that affect renal function, or who suffer from heart failure. Other special conditions that may affect an individual’s tolerance of the cathartic agent or ability to complete the administration routine include stroke, severe constipation, hematochezia, suspicious lower gastrointestinal bleeding, and mental disorders such as dementia. All ingestible bowel preparation solutions can be instilled into the stomach and duodenum through nasogastric tube or esophagogastroduodenoscope with the aid of a water irrigation pump for patients with difficulties swallowing or ingesting the large volumes of fluid required. In addition, dietary regimens based on clear liquids and low-residue foods for 1-4 d prior to the colonoscopy may be supplemental bowel preparation strategies. Achieving an effective and safe cleansing of the bowel is important for successful colonoscopy in all patients, so full knowledge of the individual’s condition and capabilities is necessary to select the most appropriate colonic cleansing agent and delivery regimen.展开更多
Bowel preparation is a core issue in colonoscopy,as it is closely related to the quality of the procedure.Patients often find that bowel preparation is the most unpleasant part of the examination.It is widely accepted...Bowel preparation is a core issue in colonoscopy,as it is closely related to the quality of the procedure.Patients often find that bowel preparation is the most unpleasant part of the examination.It is widely accepted that the quality of cleansing must be excellent to facilitate detecting neoplastic lesions.In spite of its importance and potential implications,until recently,bowel preparation has not been the subject of much study.The most commonly used agents are high-volume polyethylene glycol(PEG)electrolyte solution and sodium phosphate.There has been some confusion,even in published meta-analyses,regarding which of the two agents provides better cleansing.It is clear now that both PEG and sodium phosphate are effectivewhen administered with proper timing.Consequently,the timing of administration is recognized as one of the central factors to the quality of cleansing.The bowel preparation agent should be administered,at least in part,a few hours in advance of the colonoscopy.Several low volume agents are available,and either new or modified schedules with PEG that usually improve tolerance.Certain adjuvants can also be used to reduce the volume of PEG,or to improve the efficacy of other agents.Other factors apart from the choice of agent can improve the quality of bowel cleansing.For instance,the effect of diet before colonoscopy has not been completely clarified,but an exclusively liquid diet is probably not required,and a low-fiber diet may be preferable because it improves patient satisfaction and the quality of the procedure.Some patients,such as diabetics and persons with heart or kidney disease,require modified procedures and certain precautions.Bowel preparation for pediatric patients is also reviewed here.In such cases,PEG remains the most commonly used agent.As detecting neoplasia is not the main objective with these patients,less intensive preparation may suffice.Special considerations must be made for patients with inflammatory bowel disease,including safety and diagnostic issues,so that the most adequate agent is chosen.Identifying neoplasia is one of the main objectives of colonoscopy with these patients,and the target lesions are often almost invisible with white light endoscopy.Therefore excellent quality preparation is required to find these lesions and to apply advanced methods such as chromoendoscopy.Bowel preparation for patients with lower gastrointestinal bleeding represents a challenge,and the strategies available are also reviewed here.展开更多
文摘Adequate bowel preparation is important for successful colonoscopic examination. Several effective colonic cleansing agents are available and routinely prescribed, but each carries its own limitations and benefits from particular dosing regimens. The most frequently prescribed colonic cleansing agent, the polyethylene glycol (PEG) cathartic solution, suffers from low patient compliance in general, due to its unpalatable taste and smell coupled with the large ingested volumes required. However, PEG is preferred over other cathartics for use in individuals of advanced age, sufferers of chronic kidney disease, heart failure and inflammatory bowel disease, and women who are pregnant or lactating. The laxative agents sodium phosphate (NaP) and sodium picosulfate plus magnesium citrate have been applied and have improved patient compliance and tolerance. NaP, however, should be avoided in individuals with impaired renal function or plasma clearance, such as those with chronic kidney disease, who are taking drugs that affect renal function, or who suffer from heart failure. Other special conditions that may affect an individual’s tolerance of the cathartic agent or ability to complete the administration routine include stroke, severe constipation, hematochezia, suspicious lower gastrointestinal bleeding, and mental disorders such as dementia. All ingestible bowel preparation solutions can be instilled into the stomach and duodenum through nasogastric tube or esophagogastroduodenoscope with the aid of a water irrigation pump for patients with difficulties swallowing or ingesting the large volumes of fluid required. In addition, dietary regimens based on clear liquids and low-residue foods for 1-4 d prior to the colonoscopy may be supplemental bowel preparation strategies. Achieving an effective and safe cleansing of the bowel is important for successful colonoscopy in all patients, so full knowledge of the individual’s condition and capabilities is necessary to select the most appropriate colonic cleansing agent and delivery regimen.
文摘Bowel preparation is a core issue in colonoscopy,as it is closely related to the quality of the procedure.Patients often find that bowel preparation is the most unpleasant part of the examination.It is widely accepted that the quality of cleansing must be excellent to facilitate detecting neoplastic lesions.In spite of its importance and potential implications,until recently,bowel preparation has not been the subject of much study.The most commonly used agents are high-volume polyethylene glycol(PEG)electrolyte solution and sodium phosphate.There has been some confusion,even in published meta-analyses,regarding which of the two agents provides better cleansing.It is clear now that both PEG and sodium phosphate are effectivewhen administered with proper timing.Consequently,the timing of administration is recognized as one of the central factors to the quality of cleansing.The bowel preparation agent should be administered,at least in part,a few hours in advance of the colonoscopy.Several low volume agents are available,and either new or modified schedules with PEG that usually improve tolerance.Certain adjuvants can also be used to reduce the volume of PEG,or to improve the efficacy of other agents.Other factors apart from the choice of agent can improve the quality of bowel cleansing.For instance,the effect of diet before colonoscopy has not been completely clarified,but an exclusively liquid diet is probably not required,and a low-fiber diet may be preferable because it improves patient satisfaction and the quality of the procedure.Some patients,such as diabetics and persons with heart or kidney disease,require modified procedures and certain precautions.Bowel preparation for pediatric patients is also reviewed here.In such cases,PEG remains the most commonly used agent.As detecting neoplasia is not the main objective with these patients,less intensive preparation may suffice.Special considerations must be made for patients with inflammatory bowel disease,including safety and diagnostic issues,so that the most adequate agent is chosen.Identifying neoplasia is one of the main objectives of colonoscopy with these patients,and the target lesions are often almost invisible with white light endoscopy.Therefore excellent quality preparation is required to find these lesions and to apply advanced methods such as chromoendoscopy.Bowel preparation for patients with lower gastrointestinal bleeding represents a challenge,and the strategies available are also reviewed here.
