- Published on
Emergency And Acute Medicine – Poisoning, Gastric Decontamination
Gastric decontamination refers to techniques used to reduce gastrointestinal absorption of ingested toxins. The role of these interventions has decreased over time, and most poisoned patients are managed with supportive care and selected use of activated charcoal.
Ipecac is contraindicated in the prehospital ambulance setting and is not recommended for routine home use. In extremely rare circumstances, such as prolonged transit time with a protected airway, ipecac should only be considered after consultation with a regional poison control center. In general, it has no role in emergency department management.
Initial stabilization follows standard airway, breathing, and circulation principles. The airway must be secured in patients with decreased mental status or inability to protect their airway. Intravenous access and cardiac monitoring should be established. In patients with altered mental status due to suspected overdose, administer naloxone, thiamine, and dextrose as indicated.
Activated charcoal is the mainstay of gastric decontamination. It is produced from treated wood pulp, creating a large surface area that binds many toxins. It is most effective when administered within one hour of ingestion of a charcoal-adsorbable toxin in a patient with a protected airway. The recommended dose is 1–2 g/kg (or a charcoal-to-drug ratio of approximately 10:1), given orally or via nasogastric tube. Adverse effects include vomiting, constipation, and risk of aspiration with subsequent pneumonitis. It is contraindicated in caustic ingestions, unprotected airway, bowel obstruction, or ileus. Substances poorly adsorbed by charcoal include metals (iron, lithium, bromide, borates), alcohols, potassium, hydrocarbons, caustics, and potassium cyanide. In children, charcoal may be mixed with a palatable beverage or administered via gastric tube. Randomized trials suggest limited benefit in asymptomatic patients and a small increased risk of complications.
Multiple-dose activated charcoal may be used for toxins that undergo enterohepatic circulation or prolonged absorption. Typical dosing is 1 g/kg initially, followed by 0.5 g/kg every 2–6 hours. It is considered for salicylate and theophylline poisoning and may reduce serum concentrations of phenobarbital, phenytoin, and carbamazepine, though outcome benefit is unproven. Cathartics must never be used with multiple-dose charcoal.
Cathartics such as sorbitol, magnesium citrate, or magnesium sulfate have been used with charcoal to enhance gastrointestinal transit. Evidence does not demonstrate improved toxin elimination, and harm has been reported. Cathartics alone have no proven benefit and should be avoided. Sorbitol may be added only to the first charcoal dose. Adverse effects include dehydration, diarrhea, abdominal discomfort, and hypermagnesemia. They are contraindicated in dehydration, renal disease, and in children.
Whole-bowel irrigation involves administration of polyethylene glycol electrolyte solution to flush the gastrointestinal tract. It is indicated for toxins not well adsorbed by charcoal (such as iron or lithium), ingestion of sustained-release products, and body packers without signs of perforation. Adults receive approximately 2 L/hour and children 0.5 L/hour via nasogastric tube until rectal effluent is clear. Adverse effects include bloating, rectal irritation, and frequent bowel movements. It is contraindicated in bowel obstruction, ileus, hypotension, intestinal perforation, and unprotected airway.
Orogastric lavage involves placement of a large-bore gastric tube (32F–36F) to remove stomach contents. Its effectiveness depends on time from ingestion and the substance involved. A protected airway is mandatory prior to the procedure. Indications are rare and limited to patients presenting within one hour of a potentially lethal ingestion without a known antidote, particularly if intubated. Complications include aspiration, esophageal or gastric perforation, and patient discomfort. It is contraindicated in caustic or hydrocarbon ingestion, ingestion of large pills that cannot pass through the tube, rapidly sedating agents, or unprotected airway. In children, lavage is generally avoided due to low efficacy and increased aspiration risk. Randomized trials have shown no benefit when lavage plus charcoal is compared with charcoal alone.
Ipecac syrup, derived from Cephaelis acuminata, induces vomiting through gastric irritation and central stimulation. It delays charcoal administration and provides no benefit over charcoal alone when both are potentially effective. It has no role in emergency department care. It is contraindicated in caustic or hydrocarbon ingestion, rapidly sedating agents, and actively vomiting patients.
Key clinical considerations include avoiding ipecac in the emergency department, administering activated charcoal early in appropriate patients with a protected airway, and never combining repeated cathartics with multiple-dose activated charcoal.
Gastric decontamination refers to techniques used to reduce gastrointestinal absorption of ingested toxins. The role of these interventions has decreased over time, and most poisoned patients are managed with supportive care and selected use of activated charcoal.
Ipecac is contraindicated in the prehospital ambulance setting and is not recommended for routine home use. In extremely rare circumstances, such as prolonged transit time with a protected airway, ipecac should only be considered after consultation with a regional poison control center. In general, it has no role in emergency department management.
Initial stabilization follows standard airway, breathing, and circulation principles. The airway must be secured in patients with decreased mental status or inability to protect their airway. Intravenous access and cardiac monitoring should be established. In patients with altered mental status due to suspected overdose, administer naloxone, thiamine, and dextrose as indicated.
Activated charcoal is the mainstay of gastric decontamination. It is produced from treated wood pulp, creating a large surface area that binds many toxins. It is most effective when administered within one hour of ingestion of a charcoal-adsorbable toxin in a patient with a protected airway. The recommended dose is 1–2 g/kg (or a charcoal-to-drug ratio of approximately 10:1), given orally or via nasogastric tube. Adverse effects include vomiting, constipation, and risk of aspiration with subsequent pneumonitis. It is contraindicated in caustic ingestions, unprotected airway, bowel obstruction, or ileus. Substances poorly adsorbed by charcoal include metals (iron, lithium, bromide, borates), alcohols, potassium, hydrocarbons, caustics, and potassium cyanide. In children, charcoal may be mixed with a palatable beverage or administered via gastric tube. Randomized trials suggest limited benefit in asymptomatic patients and a small increased risk of complications.
Multiple-dose activated charcoal may be used for toxins that undergo enterohepatic circulation or prolonged absorption. Typical dosing is 1 g/kg initially, followed by 0.5 g/kg every 2–6 hours. It is considered for salicylate and theophylline poisoning and may reduce serum concentrations of phenobarbital, phenytoin, and carbamazepine, though outcome benefit is unproven. Cathartics must never be used with multiple-dose charcoal.
Cathartics such as sorbitol, magnesium citrate, or magnesium sulfate have been used with charcoal to enhance gastrointestinal transit. Evidence does not demonstrate improved toxin elimination, and harm has been reported. Cathartics alone have no proven benefit and should be avoided. Sorbitol may be added only to the first charcoal dose. Adverse effects include dehydration, diarrhea, abdominal discomfort, and hypermagnesemia. They are contraindicated in dehydration, renal disease, and in children.
Whole-bowel irrigation involves administration of polyethylene glycol electrolyte solution to flush the gastrointestinal tract. It is indicated for toxins not well adsorbed by charcoal (such as iron or lithium), ingestion of sustained-release products, and body packers without signs of perforation. Adults receive approximately 2 L/hour and children 0.5 L/hour via nasogastric tube until rectal effluent is clear. Adverse effects include bloating, rectal irritation, and frequent bowel movements. It is contraindicated in bowel obstruction, ileus, hypotension, intestinal perforation, and unprotected airway.
Orogastric lavage involves placement of a large-bore gastric tube (32F–36F) to remove stomach contents. Its effectiveness depends on time from ingestion and the substance involved. A protected airway is mandatory prior to the procedure. Indications are rare and limited to patients presenting within one hour of a potentially lethal ingestion without a known antidote, particularly if intubated. Complications include aspiration, esophageal or gastric perforation, and patient discomfort. It is contraindicated in caustic or hydrocarbon ingestion, ingestion of large pills that cannot pass through the tube, rapidly sedating agents, or unprotected airway. In children, lavage is generally avoided due to low efficacy and increased aspiration risk. Randomized trials have shown no benefit when lavage plus charcoal is compared with charcoal alone.
Ipecac syrup, derived from Cephaelis acuminata, induces vomiting through gastric irritation and central stimulation. It delays charcoal administration and provides no benefit over charcoal alone when both are potentially effective. It has no role in emergency department care. It is contraindicated in caustic or hydrocarbon ingestion, rapidly sedating agents, and actively vomiting patients.
Key clinical considerations include avoiding ipecac in the emergency department, administering activated charcoal early in appropriate patients with a protected airway, and never combining repeated cathartics with multiple-dose activated charcoal.
0 Comments
