[Value of urgent colonoscopy in diagnosis of severe acute lower gastrointestinal bleeding in patients with different bowel cleanliness].

OBJECTIVE: To investigate the value of urgent colonoscopy in the diagnosis of severe acute lower gastrointestinal bleeding and the optimal bowel preparation before examination. METHODS: The clinical data were collected from 188 patients undergoing wither urgent or elective colonoscopy for severe acute lower gastrointestinal bleeding in Nanfang Hospital. Univariate analysis was used to assess the effect of the timing of colonoscopy on the diagnostic rate of hemorrhage, and a multivariate model which stratified bowel cleanliness was used to analyze the impact of bowel cleanliness on the diagnostic rate of urgent colonoscopy. RESULTS: Of the 188 patients, 118 underwent urgent colonoscopy and 70 underwent elective colonoscopy examinations. The diagnostic rates were comparable between the two groups (44.1% vs 41.4%, P=0.724), but urgent colonoscopy resulted in a significantly higher diagnostic rate for identifying the bleeding source (32.2% vs 18.6%, P=0.041). The proportion of the patients taking oral laxatives was significantly lower in urgent colonoscopy group (P<0.001). Oral laxatives versus enema resulted in good, moderate, and poor bowel cleanliness in 63.6% vs 13.5%, 28.6% vs 24.3%, and 7.8% vs 62.2% of the patients (P<0.001). Univariate analysis indicated that good bowel cleanliness was associated with a significantly higher diagnostic rate of colonoscopy than poor bowel cleanliness (P=0.012). Multivariate analysis showed that with good bowel cleanliness, urgent colonoscopy yielded a significantly higher diagnostic rate than elective colonoscopy (P=0.030); subgroup analyses suggested that good bowel cleanliness improved the diagnostic rate of urgent colonoscopy as compared with poor bowel cleanliness (P=0.015). CONCLUSION: In patients with good bowel cleanliness, urgent colonoscopy yields a higher diagnostic rate than elective colonoscopy for severe acute lower gastrointestinal bleeding. Poor bowel cleanliness resulting from bowel preparation by enema significantly lowers the diagnostic performance of urgent colonoscopy. Oral laxatives are recommended over enemas for bowel preparation before urgent colonoscopy when the patients have stable hemodynamics.

Small bowel MR imaging: 1.5T versus 3T.

This article provides practical information regarding patient preparation schemes for small bowel MR imaging, and offers dedicated pulse sequence protocols for 1.5-T and 3-T MR imaging scanners, with specific emphasis on the advantages and remaining limitations of the higher field strength.

Anthranoid laxatives influence the absorption of poorly permeable drugs in human intestinal cell culture model (Caco-2).

Interactions between widely used anthranoid laxatives and other simultaneously administered drugs are not known. In this paper, the influence of rhein, danthron, sennidins A/B, sennosides A/B, and senna leaf infusion was investigated on the permeability of furosemide, ketoprofen, paracetamol, propranolol, verapamil, digoxin, and Rhodamine 123 across Caco-2 monolayers. The effects on monolayer integrity ([(14)C]mannitol permeability, TEER) were also determined. The in vitro absorption of highly permeable drugs was not strongly affected during co-administration of the laxatives. Furosemide permeability was enhanced by rhein and danthron (3.6 and 3.0-fold), which may partly be due to opening of the paracellular spaces and/or effects on active efflux. However, the secretory permeability of digoxin and Rho 123 was not strongly affected by rhein and danthron, suggesting that inhibition of MDR1 was not responsible for the increased permeation of furosemide. The absorptive permeability of digoxin was decreased by rhein and danthron, offering evidence for effects on apical membranes. The effects on monolayer integrity were detectable, but reversible. According to presented experiments, daily use of laxatives with well-absorbing drugs would seem unlikely to affect drug permeability, but the effects on the absorption of poorly permeable drugs cannot be excluded.

Laxatives.

Laxatives are used to treat constipation and to prepare the bowel before surgery or other investigative procedures. But, if used inappropriately, they can be dangerous, which can cause problems as many are sold over the counter. Carol McLoughlin looks at the types of laxative available, and how to help patients use them properly.

Nursing role in the management of constipation: use of laxatives.

Constipation is extremely common and may affect a variety of patients from different age groups. This article outlines the causes of constipation and describes the nurse's role in the management of patients with constipation, from assessment to intervention. The skills required of the nurse, including taking a detailed history from the patient, the subsequent examination, and the administration of laxatives are discussed in detail. Nurses are best placed to assess, plan, implement and evaluate care for patients presenting with constipation. The article stresses the need for healthcare professionals to aim to prevent constipation and to identify early those patients at risk of developing constipation, to ensure that patients' needs are met fully. Recommendations for good practice are given.

Laxative use in the community-dwelling elderly.

BACKGROUND: Constipation, a common and sometimes severe problem in the elderly, is often treated with laxatives. OBJECTIVE: The purpose of this study was to determine the prevalence of laxative use and identify determinants of such use among representative black and white community-dwelling elderly persons. METHODS: This was a cross-sectional survey of 4136 participants at baseline (1986-1987) in the Duke University Established Populations for Epidemiologic Studies of the Elderly. Data on demographic characteristics, health status, health service use, and use of prescription and over-the-counter drugs were collected in participants' homes. Use of the following types of laxatives was examined: bulking, hyperosmotic, lubricant, stimulant, stool softener, saline, and miscellaneous agents. RESULTS: It was found that 10.2% of participants used > or =1 laxative. Stimulants and bulking agents were the most commonly used classes. Only 11.6% of laxative users reported concurrent consumption of > or =2 laxatives. Multivariate logistic regression analyses indicated that laxative use was more likely in women (adjusted OR, 1.78; 95% CI, 1.34-2.37), those with >4 physicians visits in the previous year (adjusted OR, 1.72; 95% CI, 1.16-2.53), those unable to walk a half mile (adjusted OR, 1.44; 95% CI, 1.11-1.87), and those using > or =4 over-the-counter nonlaxative medications (adjusted OR, 2.09; 95% CI, 1.15-3.81). A nonsignificant association was seen between laxative use and the use of anticholinergic agents (adjusted OR, 1.38; 95% CI, 1.00-1.89). CONCLUSIONS: Laxative use is common among community-dwelling elderly persons and is related to specific factors concerning sociodemographics, health status, and access to health care. Studies are needed that examine the impact of laxative use on bowel function and quality of life in the elderly.

Status of certain additional over-the-counter drug category II and III active ingredients. Final rule.

The Food and Drug Administration (FDA) is issuing a final rule stating that the stimulant laxative ingredients aloe (including aloe extract and aloe flower extract) and cascara sagrada (including casanthranol, cascara fluidextract aromatic, cascara sagrada bark, cascara sagrada extract, and cascara sagrada fluidextract) in over-the- counter (OTC) drug products are not generally recognized as safe and effective or are misbranded. This final rule is part of FDA's ongoing OTC drug product review.

Constipation: evaluation and management.

Constipation is a common symptom that can result from several disorders. Most patients with chronic constipation do not have a medical disorder contributing to the constipation and, therefore, require limited evaluation. Initial intervention should include dietary measures and fiber supplements; however, if fiber supplementation is ineffective, other agents can be used. Surgery should be reserved for patients who meet specific clinical criteria.

Constipation.

Most patients with chronic constipation respond to dietary measures, fiber supplements, or laxatives. For those who do not, diagnostic tests of colonic and anorectal function help to select appropriate treatments. Therapeutic options, pharmacologic agents, and surgery, the last resort, are discussed in this article.

Toxicity of commonly used laxatives.

Laxatives have a particularly marked abuse potential. Since they are available without prescription, physicians have no influence whatsoever on frequency of intake and dosage. The stimulant laxatives are preferentially abused since they are particularly cheap and the nature of their effect makes them appear suitable to users for non-intended purposes; advertising sometimes reinforces such impressions. Stimulants of plant and chemical origin can certainly be regarded as aggressive chemical substances that are pharmacologically active. Available data suggest that it would be advisable to bring the use of these substances under medical supervision since their widespread abuse and the associated risks can only be substantially reduced by such action. This review summarises toxicological data of stimulant laxatives and other freely available but more safe compounds such as lactulose.