Gastrointestinal decontamination and the prevention of absorption

摘要

The benefit of performing gastrointestinal decontamination in many patients who have had overdoses has not been clearly documented and may have significant complications. An analysis of the literature on gastrointestinal decontamination allows qualitative conclusions about broad treatment measures but does not produce answers to complex clinical problems. Syrup of ipecac remains the method of choice for gastrointestinal decontamination in the home because of its availability, safety, reliability, and compliance. However, its effectiveness is limited by a slow onset of action and the postingestion initiation time. The prolonged emetic action of syrup of ipecac may interfere with the administration of activated charcoal and oral antidotes. In the emergency department the use of syrup of ipecac is limited to substances not adsorbed by activated charcoal and those too large to be removed by the orogastric tube. Gastric lavage is useful when time is of the essence and in evacuating liquids and smaller particles. Its effectiveness is limited by the postingestion initiation time. Neither syrup of ipecac emesis nor gastric lavage completely evacuates the stomach, and both leave substantial gastric residual of the ingested substance. Neither method obviates careful follow-up and observation in significant poisonings. Activated charcoal absorbs many substances, even beyond the pylorus. Although activated charcoal shortens the nonrenal half-life and the area under the concentration curve of many substances, there is controversy regarding its effect on the clinical course of the poisoned patient. Activated charcoal often requires a small nasogastric tube to ensure compliance and may interfere with oral antidotes. There is no scientific proof that cathartics are effective in gastrointestinal decontamination. Whole bowel irrigation is still investigational but it may be useful in certain situations such as removal of long-acting preparations, bezoars, and containers of contraband. Gastrointestinal decontamination procedures should not be routine but should be carefully individualized based on the substance ingested, clinical presentation, and the time of ingestion. Gastrointestinal decontamination should be preserved for patients who are most likely to benefit because the procedures carry some risk. None of the present methods of gastrointestinal decontamination has proven universally effective.