Gastric lavage and emesis in the treatment of ingested poisons: a review and a clinical study of lavage in ten adults

Evaluation of residual toxic substances in the stomach using upper gastrointestinal endoscopy for management of patients with oral drug overdose on admission: a prospective, observational study

The guidelines on the indications for gastric lavage were published in 1997, and a less-aggressive initial approach has been used for poisoned patients. Clinical studies have shown that the outcomes of retrieval of residual toxic substances in the stomach are variable and that no beneficial effect is obtained. However, the presence of residual toxic substances in the stomach before gastric lavage has not been estimated. The objective of this study was to evaluate the residual stomach contents on admission of patients with oral drug overdoses using upper gastrointestinal endoscopy. A 2-year prospective study of 167 patients with oral drug overdoses was performed. Endoscopy was performed on admission to observe the gastric body, fornix, and pyloric antrum. Patients were classified into 3 groups according to the digestive phase (tablet/food phase, soluble/fluid phase, and reticular/empty phase). The groups were compared with respect to time elapsed since ingestion, and numbers and variety of orally overdosed drugs. The numbers of patients in each phase were as follows: tablet/food phase, 73; soluble/fluid phase, 50; and reticular/empty phase, 44. The tablet/food and soluble/fluid phase groups contained the greatest numbers of patients who presented within 1 to 2 hours since ingestion. In the tablet/food group, only 12 of 73 patients (16%) presented within 1 hour since ingestion, and 3 patients presented >12 hours since ingestion. In the soluble/fluid phase group, only 9 of 50 patients (18%) presented within 1 hour since ingestion, and 2 patients presented >12 hours since ingestion. The reticular/empty phase group contained the greatest number of patients presenting within 2 to 4 hours since ingestion, and 3 patients presented within 1 hour since ingestion. The residual stomach contents before lavage were variable in all of the groups. The residual gastric content before the performance of gastric lavage is variable in overdosed patients on admission. This may influence the efficiency of gastric lavage with respect to retrieval of residual toxic substances in the stomach. This study may contribute to the development of a strategy for treating patients who have orally overdosed on drugs in the future.

David R. Boyd lecture in trauma care and emergency medical systems: "The surgical complications of toxins."

Toxins have had major roles in our societies for thousands of years. Interactions between surgeons, both generalists and subspecialists, and those caring for poisoned patients have been extensive throughout history. The advancement of the science of toxicology, the development of regional poison control centers, the development of emergency medicine, and the development of the subspecialty of medical toxicology have led to more appropriate and creative interactions between medical toxicologists, emergency physicians, and surgeons. This article will review the diverse interfaces between the medical toxicologist and the surgeon.

Prevention of drug absorption in simulated theophylline overdose

1. The effects of emesis, gastric lavage and oral activated charcoal on theophylline absorption were compared in healthy volunteers. 2. One of four regimes (ipecacuanha-induced emesis, gastric lavage, oral activated charcoal and no treatment) was randomly chosen one hour after a simulated overdose with sustained-release theophylline on four separate occasions in twelve healthy volunteers. 3. Syrup of ipecacuanha produced emesis in all twelve volunteers but only seven vomited any tablets. Gastric lavage yielded tablets in only one volunteer. 4. The mean systemic availabilities (areas under the concentration-time curves relative to control) of theophylline for ipecacuanha-induced emesis, gastric lavage and charcoal, were 107.1%, 101.1% and 16.9%, respectively. 5. Oral activated charcoal was thus highly effective, while gastric lavage and emesis were ineffective in preventing theophylline absorption. Activated charcoal is potentially the most effective first-line treatment for acute overdosage with sustained-release theophylline tablets.

Pediatric gastrointestinal decontamination in acute toxin ingestion

The appropriate implementation of the various modalities of gastrointestinal (GI) decontamination is critical in the management of the pediatric patient who is examined in the emergency department or private office after an acute ingestion. Gastrointestinal decontamination includes gastric lavage, syrup of ipecac, activated charcoal, and whole bowel irrigation. Clinical studies have delineated the role and efficacy of these procedures. Trends in GI decontamination place less emphasis on ipecac and gastric lavage and more emphasis on activated charcoal alone in the patient with a mild overdose. Gastric lavage is indicated in serious ingestion and is most effective if done soon after the exposure. Whole bowel irrigation is the newest addition and has important clinical use in the treatment of serious iron ingestions as well as in older adolescent cocaine body suffers and packers. Indications and contraindications of the various forms of GI decontamination are discussed and relevant clinical studies are reviewed.

Recovery of cyclic antidepressants with gastric lavage

The role of lavage fluid volume in recovery of cyclic antidepressant with gastric lavage was determined in 13 patients treated for moderate to severe cyclic antidepressant intoxication. An orogastric tube was placed, gastric contents aspirated, and gastric lavage performed with 60 to 180 mL aliquots of tap water or 0.9% NaCl for irrigation. A volume of 12.8 +/- 4.4 liters of lavage fluid was instilled, and 97.6 +/- 6.9% of this volume was recovered. The recovered aspirate and lavage fluid were inspected for the presence of particulate matter and saved in 4 to 5 liter collections. Determination of cyclic antidepressant and metabolite concentrations was performed using gas chromatography-mass spectrometry, and the amount of cyclic antidepressant recovered was calculated. The mean total amount recovered was 110 mg and ranged from 2.4 mg to 342 mg. Of the total amount recovered, 88% +/- 13% was recovered in the first 4 to 5 liters of lavage fluid. An estimate of the dose ingested was available in 7 patients, with 8.7% (0.4% to 21.7%) of the estimated dose recovered by lavage. There were no cases of significant drug recovery in clear lavage fluid. We conclude that if gastric lavage is undertaken in cyclic antidepressant intoxications, it should utilize 5 liters initially and then continue only if particulate matter is seen.

The knee-chest position does not improve the efficacy of ipecac-induced emesis

Previous studies have shown that ipecac-induced emesis, even if instituted very early, removes only a mean of 28% to 45% of an ingested tracer. Because vomiting is an ancient reflex that occurs in mammals, reptiles, and other animals, we speculated that, in humans, maintaining a sitting rather than a horizontal posture during induced emesis might decrease the efficacy of gastric emptying. To test this hypothesis, 20 normal fasting adult subjects underwent induced emesis in the knee-chest position on one day and in the sitting position on another. Twenty-five 100-micrograms tablets of cyanocobalamin were ingested as a tracer along with 250 mL tap water. Ten minutes after tracer ingestion, 30 mL ipecac syrup and 640 mL tap water were swallowed. All resulting vomitus was homogenized, frozen, and later assayed for cobalt using atomic absorption spectrophotometry. There was no difference in mean tracer recovery with the two positions: knee-chest, 47.2% v sitting, 46.9% (paired t test, P greater than .95). Analysis of cobalt recovery for all 40 episodes of emesis revealed a mean of 51.2 +/- 23.7 (SD) micrograms out of 108.7 micrograms total cobalt ingested (95% Cl, 43.6 to 58.7 micrograms). This represented 47.1% of the administered tracer dose (95% Cl, 40.1% to 54.0%). Even if initiated only ten minutes after an ingestion, ipecac-induced emesis removes an average of less than half of an ingested tracer dose, with a high degree of intersubject variability. Horizontal patient positioning does not appear to improve the efficacy of this procedure.

Toxicodynamic approach to management of the poisoned patient

We recommend a toxicodynamic approach to the management of the poisoned patient. We define the period between ingestion and onset of toxic manifestations (clinical or laboratory) as the preclinical phase, during which the management of the patient necessarily depends solely on the history of ingestion and the predicted toxicity. In the toxic phase during which the patient shows clinical or laboratory evidence of toxicity, the history, clinical status (signs, symptoms, drug levels, laboratory parameters), and toxicodynamics should guide the therapy. In the resolution phase, when the patient shows clinical improvement and declining drug levels, treatment should be based on clinical status. Gastrointestinal decontamination is critical in the first two phases and may be of value during the resolution phase until the body drug burden declines to safe levels. We recommend an aggressive approach to gastrointestinal decontamination, especially in the preclinical phase. With a history of a potentially toxic ingestion of an absorbable drug, an observation period until passage of a charcoal-laden stool should be achieved before discharge of the patient.

Oral activated charcoal in the treatment of intoxications. Role of single and repeated doses

Activated charcoal has an ability to adsorb a wide variety of substances. This property can be applied to prevent the gastrointestinal absorption of various drugs and toxins and to increase their elimination, even after systemic absorption. Single doses of oral activated charcoal effectively prevent the gastrointestinal absorption of most drugs and toxins present in the stomach at the time of charcoal administration. Known exceptions are alcohols, cyanide, and metals such as iron and lithium. In general, activated charcoal is more effective than gastric emptying. However, if the amount of drug or poison ingested is very large or if its affinity to charcoal is poor, the adsorption capacity of activated charcoal can be saturated. In such cases properly performed gastric emptying is likely to be more effective than charcoal alone. Repeated dosing with oral activated charcoal enhances the elimination of many toxicologically significant agents, e.g. aspirin, carbamazepine, dapsone, dextropropoxyphene, cardiac glycosides, meprobamate, phenobarbitone, phenytoin and theophylline. It also accelerates the elimination of many industrial and environmental intoxicants. In acute intoxications 50 to 100g activated charcoal should be administered to adult patients (to children, about 1 g/kg) as soon as possible. The exceptions are patients poisoned with caustic alkalis or acids which will immediately cause local tissue damages. To avoid delays in charcoal administration, activated charcoal should be a part of first-aid kits both at home and at work. The 'blind' administration of charcoal neither prevents later gastric emptying nor does it cause serious adverse effects provided that pulmonary aspiration in obtunded patients is prevented. In severe acute poisonings oral activated charcoal should be administered repeatedly, e.g. 20 to 50g at intervals of 4 to 6 hours, until recovery or until plasma drug concentrations have fallen to non-toxic levels. In addition to increasing the elimination of many drugs and toxins even after their systemic absorption, repeated doses of charcoal also reduce the risk of desorbing from the charcoal-toxin complex as the complex passes through the gastrointestinal tract. Charcoal will not increase the elimination of all substances taken. However, as the drug history in acute intoxications is often unreliable, repeated doses of oral activated charcoal in severe intoxications seem to be justified unless the toxicological laboratory has identified the causative agent as not being prone to adsorption by charcoal. The role of repeated doses of oral activated charcoal in chronic intoxication has not been clearly defined.(ABSTRACT TRUNCATED AT 400 WORDS)

Efficacy of ipecac-induced emesis, orogastric lavage, and activated charcoal for acute drug overdose

The efficacy of ipecac-induced emesis, large-bore orogastric lavage, and activated charcoal as gastrointestinal decontamination procedures after acute drug overdose is unknown. Using an ampicillin overdose model, these three procedures were compared with one another and to a control ingestion in ten human volunteers. Serial serum ampicillin levels were used to compute the areas under the concentration vs time curves (AUC) for each study. The reductions of ampicillin absorption compared to control were as follows: orogastric lavage 32% (NS), ipecac-induced emesis 38% (P less than .01), and activated charcoal 57% (P less than .01). This model examines each intervention in a mutually exclusive fashion. It supports activated charcoal administration as the primary gastrointestinal decontamination procedure after acute drug overdose.

Ipecac-induced emesis versus gastric lavage: a controlled study in normal adults

Ipecac-induced emesis and gastric lavage are the two procedures most widely used to evacuate the stomachs of patients who have ingested poisons. To resolve a long-standing controversy over the relative efficacy of these two methods, the authors carried out a controlled study in which they administered 25 100-micrograms tablets of cyanocobalamin (vitamin B12) to 18 fasting normal adult volunteers on two separate days. On one day, each subject had emesis induced with 30 ml of ipecac syrup followed by 1,000 ml of tap water; on another day, each underwent gastric aspiration and lavage with a 1.1-cm orogastric tube using 3 l of fluid. Both procedures were begun 10 minutes after the ingestion. The recovered vomitus or gastric washings from each procedure were then analyzed for elemental cobalt using atomic absorption spectrophotometry. The mean rate of recovery of the ingested tracer with ipecac-induced emesis was only 28%, whereas gastric lavage resulted in retrieval of 45% (paired t-test, P less than 0.005). In this study, carefully performed gastric lavage was the more effective method of gastric evacuation of tablets in the adult subject.

Gastrointestinal decontamination for acute poisoning

Gastric decontamination remains an important element in the therapy of pediatric poisoning; however, several issues remain unresolved. Additional studies, particularly in the clinical setting, are necessary to establish optimal therapeutic recommendations. Based on the data presented in this review, the following general recommendations can be made for gastric decontamination in children: If it is necessary to remove an ingested toxin, ipecac syrup is the preferred method if contraindications to its use are not present. The dose should be 30 ml in children older than 1 year of age and 10 ml in children 6 to 12 months of age. Pending further studies, the use of emetics in children younger than 6 months of age cannot be generally recommended, particularly in the home setting. Gastric lavage should be considered to be of very limited use in pediatric patients. Lavage using small nasogastric tubes, except under special circumstances, is nonproductive and cannot be advocated. If it must be used, a large-bore orogastric hose should be used. Administration of activated charcoal prior to lavage should be considered. In situations in which prompt induction of emesis is not possible or contraindications to emesis exist, activated charcoal followed by, or mixed with, a cathartic (preferably sorbitol) should be used as an alternative to removal of gastric contents. Patients with significant symptoms from ingestion requiring hospitalization should receive repeat doses of charcoal and cathartic until symptoms resolve. Activated charcoal should be given in conjunction with other appropriate therapies. Although the data to substantiate this recommendation are limited, particularly in pediatric patients, it is a benign therapy that holds promise of increasing drug elimination.

Gastric emptying. Risk versus benefit in the treatment of acute poisoning

This review examines the various clinical options used to elicit gastric emptying, viz. drug-induced emesis, mechanical pharyngeal stimulation, gastric lavage, and catharsis. Apomorphine and syrup of ipecac are the 2 drugs most frequently used for induction of emesis. Both agents act centrally and, in addition, syrup of ipecac has a peripheral action. Toxins ingested or foods previously eaten may inhibit or enhance emetic action by interfering with mediating and conducting mechanisms. Studies indicate that both syrup of ipecac and apomorphine are similarly effective in inducing emesis; however, apomorphine has a shorter reaction time compared with syrup of ipecac. There are more risks involved with the use of apomorphine, since it causes central nervous system and respiratory depression. Syrup of ipecac has been shown to be relatively safe when used in its recommended dosage for emesis. However, several toxicities have been reported with the use of the fluid extract of ipecac. Emesis is contraindicated in patients who are obtunded or comatose, and in patients who have ingested stimulants, some hydrocarbons, or corrosives. Mechanical pharyngeal stimulation is a simple method of inducing emesis; however, it is often unsuccessful and rarely recovers a significant portion of the gastric contents. Gastric lavage is a procedure which has been relied upon for over a century. Its effectiveness is dependent on the nature, form, and dosage of the poison, latency between time of ingestion and lavage, and technique. In clinical experiments studying gastric lavage, it has been noted that the procedure is most beneficial 1 to 2 hours postingestion for the majority of poison ingestions. Lavage also provides an excellent route for activated charcoal and selected antidotes. Gastric lavage may pose several risks to the patient, including obstruction and contamination of the airways and oesophageal damage. Contraindications for gastric lavage are similar to those for emesis except that it may be safer to use in obtunded, comatose, or uncooperative patients. Cathartics used during initial poisoning therapy are usually the saline cathartics. They elicit an osmotic reaction in the small intestine which results in increased intraluminal fluid bulk, hyperperistalsis, and subsequent propulsion of contents. Cathartics have also been shown to stimulate the secretion of cholecystokinin, which is thought to have similar effects on the intestine. Cathartics have not been shown to significantly enhance drug elimination from the gastrointestinal tract.(ABSTRACT TRUNCATED AT 400 WORDS)

Automated gastric lavage and a comparison of 0.9% normal saline solution and tap water irrigant

Gastric lavage is used frequently in the emergency treatment of upper gastrointestinal hemorrhage, toxin ingestion, drug overdose, and other cases requiring repetitive gastric irrigation. An effective automatic method of gastric lavage is described and evaluated. The use of tap water versus 0.9% normal saline solution also is compared. There is no difference in prelavage and postlavage blood cell concentrations or electrolyte profile with either irrigant. The advantages of tap water lavage fluid are discussed.

Management of acutely poisoned patients without gastric emptying

During an 18-month period, 592 acute oral drug overdose patients were studied prospectively in a controlled, randomized fashion to determine the efficacy of gastric emptying procedures in altering clinical outcome. Patients presenting on even-numbered days had no gastric emptying procedures performed, and they were compared to patients presenting on odd-numbered days who received either syrup of ipecac or gastric lavage. Patients were carefully followed for evidence of subsequent clinical improvement or deterioration after initial management. Syrup of ipecac did not significantly alter the clinical outcome of patients who were awake and alert on presentation to the emergency department (ED). Gastric lavage in obtunded patients led to a more satisfactory clinical outcome (P less than .05) only if performed within one hour of ingestion. Gastric emptying procedures in the ED for initial treatment of drug overdose are generally not of benefit unless gastric lavage is performed within one hour of ingestion in obtunded patients.

Inefficacy of gastric emptying procedures

Gastric lavage or ipecac-induced emesis are routinely recommended in the management of the acutely poisoned patient. Efficacy of either procedure has not been shown. Three cases are described clearly demonstrating inefficacy of emesis and wide bore orogastric lavage. The role of these procedures requires careful controlled evaluation. Until the publication of supportive data, their efficacy is unproven.

Modifications in the technique of gastric lavage

A simple experimental model was used to demonstrate the effects of water temperature and mechanical agitation in removing pills during gastric lavage. It was nearly impossible to remove pills from an artificial stomach using room temperature water and no mechanical agitation, Using warm tap water and repetitive compressions of the artificial stomach, the pills were consistently removed with ease. We recommend that gastric lavage for poisoning victims include two phases, the first using traditional lavage technique, and the second using larger aliquots, warm lavage fluid, and massage of the epigastrium.