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Introduction

  1. Surface decontamination
    1. Skin. Corrosive agents rapidly injure the skin and must be removed immediately. In addition, many toxins are readily absorbed through the skin, and systemic absorption can be prevented only by rapid action. Table II-20 lists several corrosive chemical agents that can have systemic toxicity, and many of them are readily absorbed through the skin.
      1. Be careful not to expose yourself or other care providers to potentially contaminating substances. Wear protective gear (gloves, gown, and goggles) and wash exposed areas promptly. Contact a regional poison control center for information about the hazards of the chemicals involved; in the majority of cases, health care providers are not at significant personal risk for secondary contamination, and simple measures such as emergency department gowns and plain examination gloves, and a well-ventilated room, provide sufficient protection. For radiation and other hazardous materials incidents, see also Section IV (Emergency Medical Response to Hazardous Materials Incidents).
      2. Remove contaminated clothing and flush exposed areas with copious quantities of tepid (lukewarm) water or saline. Wash carefully behind ears, under nails, and in skin folds. Use soap and shampoo for oily substances.
      3. There is rarely a need for chemical neutralization of a substance spilled on the skin. In fact, the heat generated by chemical neutralization can potentially create worse injury. Some of the few exceptions to this rule are listed in Table I-35.
      4. Extravasation of some parenteral medications (eg, chemotherapeutic agents, concentrated potassium, dextrose, or calcium solutions, phenytoin, IV contrast dye) can cause skin and soft tissue necrosis. Stop the infusion immediately and apply a warm towel to facilitate systemic absorption by vasodilation. Depending on the agent, more specific therapies, such as local injection of hyaluronidase (which transiently increases absorptive capacity of subcutaneous tissues) or neutralizing agents may be indicated.
    2. Eyes. The cornea is especially sensitive to corrosive agents and hydrocarbon solvents that may rapidly damage the corneal surface and lead to permanent scarring.
      1. Act quickly to prevent serious damage. Remove any contact lenses. If available, instill local anesthetic drops in the eye to facilitate irrigation. Flush exposed eyes with copious quantities of fluids (lactated Ringer's solution is closest in composition to tear fluid so it is preferred, but saline or even tap water can be used if these are more readily available).
      2. Apply Morgan's lenses (ocular irrigation device) after placing the victim in a supine position. Connect the tubing to lactated Ringer's solution (preferred) or normal saline, and irrigate 1 L of fluid. If Morgan's lenses are not available, nasal cannula tubing can be repurposed to direct a stream of water into the medial aspect of the eye. Tape the nasal cannula to the bridge of the nose and connect the tubing to IV fluid bags. Reassure the patient and check frequently to ensure that each prong drips fluid into the medial canthus.
      3. If the offending substance is an acid or a base, check the pH of the victim's tears after irrigation and continue irrigation until the pH returns to normal.
      4. Do not instill neutralizing solution in an attempt to normalize the pH; there is no evidence that such treatment works, and it may further damage the eye.
      5. After irrigation is complete, check the conjunctival and corneal surfaces carefully for evidence of full-thickness injury. Check visual acuity and perform a fluorescein examination of the eye with a Wood lamp to reveal corneal injury.
      6. Patients with serious conjunctival or corneal injury should be referred to an ophthalmologist immediately.
    3. Inhalation. Agents that injure the pulmonary system may be acutely irritating gases or fumes and may have good or poor warning properties (Gases, Irritant).
      1. Be careful not to expose yourself or other care providers to toxic gases or fumes without adequate respiratory protection.
      2. Remove the victim from exposure and give supplemental humidified oxygen, if available. Assist ventilation if necessary (Airway).
      3. Observe closely for evidence of upper respiratory tract edema, which is heralded by a hoarse voice and stridor and may progress rapidly to complete airway obstruction. Endotracheally intubate patients who show evidence of progressive airway compromise.
      4. Also observe for late onset noncardiogenic pulmonary edema resulting from more slowly acting toxins (eg, nitrogen oxide, phosgene), which may take several hours to appear. Early signs and symptoms include dyspnea, hypoxemia, and tachypnea (Heparins).
  2. Gastrointestinal decontamination. There remains controversy about the role of gastric emptying and activated charcoal to decontaminate the gastrointestinal tract in the management of ingested poisons. There is little support in the medical literature for gut-emptying procedures, and after a delay of 60 minutes or more, only a small proportion of the ingested dose is likely to be removed by induced emesis or gastric lavage. Moreover, studies suggest that in the typical overdosed patient, simple oral administration of activated charcoal without prior gut emptying is probably just as effective as the traditional sequence of gut emptying followed by charcoal. For many overdose patients who have ingested a small dose, a relatively nontoxic substance, or a drug that is rapidly absorbed, it is even questionable whether activated charcoal makes any difference in outcome.However, there are some circumstances in which aggressive gut decontamination may potentially be life-saving and is advised, even after more than 1-2 hours. Examples include ingestion of highly toxic drugs (eg, calcium antagonists, colchicine), ingestion of drugs not adsorbed to charcoal (eg, iron, lithium), ingestion of massive amounts of a drug (eg, 150-200 aspirin tablets), and ingestion of sustained-release or enteric-coated products.
    1. Emesis. Syrup of ipecac-induced emesis is no longer recommended in the home, prehospital, or emergency settings. Adverse effects of ipecac include persistent vomiting with the potential for esophageal tear or rupture, electrolyte derangements, dehydration, and cardiomyopathy from repeated daily use (eg, by bulimic patients). Other emetics such as manual digital stimulation, copper sulfate, salt water, sodium bicarbonate, mustard water, apomorphine, and potassium permanganate are unsafe and should not be used.
    2. Gastric lavage. Gastric lavage is only occasionally performed in hospital emergency departments. There is little clinical evidence to support its routine use. Gastric lavage may be effective for recently ingested liquid substances. However, it does not reliably remove undissolved pills or pill fragments (especially sustained-release or enteric-coated products). In addition, the procedure may delay the administration of activated charcoal and may hasten the movement of drugs and poisons into the small intestine, especially if the patient is supine or in the right decubitus position. Gastric lavage is not necessary for small-to-moderate ingestions of most substances if activated charcoal can be given promptly.
      1. Indications
        1. To remove ingested liquid and solid drugs and poisons when the patient has taken a massive overdose or has ingested a particularly toxic substance. Lavage is more likely to be effective if initiated within 30-60 minutes of the ingestion, before gastric emptying has occurred.
        2. A nasogastric tube may be needed in order to administer activated charcoal and whole-bowel irrigation to patients unwilling or unable to swallow them.
        3. To dilute and remove corrosive liquids from the stomach and to empty the stomach in preparation for endoscopy.
      2. Contraindications
        1. Obtunded, comatose, or convulsing patients. Because it may disturb the normal physiology of the esophagus and airway protective mechanisms, gastric lavage must be used with caution in obtunded patients whose airway reflexes are dulled. In such cases, endotracheal intubation with a cuffed endotracheal tube should be performed first to protect the airway.
        2. Ingestion of sustained-release or enteric-coated tablets. (Owing to the size of most tablets, lavage is unlikely to return intact tablets, even through a 40F orogastric hose.) In such cases, whole-bowel irrigation (see below) is preferable.
        3. Use of gastric lavage or placement of a nasogastric tube after ingestion of a corrosive substance is controversial; some gastroenterologists recommend that insertion of a gastric tube and aspiration of gastric contents be performed as soon as possible after liquid caustic ingestion to remove corrosive material from the stomach and to prepare for endoscopy. If performed, it should done by experienced personnel with post-procedure radiographs and continuous monitoring for complications.
      3. Adverse effects
        1. Perforation of the esophagus or stomach.
        2. Bleeding from mucosal trauma during passage of the tube.
        3. Inadvertent cannulation of trachea or bronchial tree.
        4. Vomiting resulting in pulmonary aspiration of gastric contents in an obtunded patient without a secured airway.
      4. Technique
        1. If the patient is deeply obtunded, first protect the airway by intubating the trachea with a cuffed endotracheal tube.
        2. Place the patient in the left lateral decubitus position. This helps prevent ingested material from being pushed into the duodenum during lavage.
        3. Measure the approximate length of the tube insertion by marking the distance from the left mastoid to the sternal xiphoid. Insert a large gastric tube through the mouth or nose and into the stomach (36-40F [catheter size] in adults; a smaller tube will suffice for removal of liquids or for the administration of activated charcoal). Check tube position with air insufflation while listening with a stethoscope positioned on the patient's stomach. Bedside ultrasound or rapid portable x-ray can also help confirm placement.
        4. Withdraw as much of the stomach contents as possible. If the ingested poison is a toxic chemical that may contaminate hospital personnel (eg, cyanide, organophosphate insecticide), take steps to isolate it immediately (eg, use a self-contained wall suction unit).
        5. Administer activated charcoal, 60-100 g (1 g/kg; see Item II.C below), down the tube before starting lavage to begin adsorption of material that may enter the intestine during the lavage procedure.
        6. Instill tepid (lukewarm) water or saline, 200- to 300-mL aliquots, and remove by gravity or active suction. Use repeated aliquots for a total of 2 L or until the return is free of pills or toxic material. Caution: Use of excessive volumes of lavage fluid or plain tap water can result in hypothermia or electrolyte imbalance in infants and small children.
    3. Activated charcoal is a highly adsorbent powdered material made from thermally treated wood pulp. Owing to its very large surface area, it is highly effective in adsorbing most toxins when given in a ratio of approximately 10:1 (charcoal to toxin). A few substances are poorly adsorbed to charcoal (Table I-36), and in some cases this requires a higher ratio (eg, for cyanide a ratio of about 100:1 is necessary). Studies in volunteers taking nontoxic doses of various substances suggest that activated charcoal given alone without prior gastric emptying is as effective as or even more effective than emesis and lavage procedures in reducing drug absorption. However, there are no well-designed prospective randomized clinical studies demonstrating its effectiveness in poisoned patients, and there is a risk of vomiting and subsequent aspiration of gastric contents. As a result, some toxicologists advise against its routine use.
      1. Indications
        1. Used after ingestion to limit drug absorption from the gastrointestinal tract if it can be given safely and in a reasonable time period after the ingestion.
        2. Charcoal can be administered even when the offending substance does not adsorb well to charcoal, if there is concern that other substances have been co-ingested.
        3. Repeated oral doses of activated charcoal may enhance the elimination of some drugs from the bloodstream (Repeat-dose activated charcoal).
      2. Contraindications. Ileus without distension is not a contraindication to a single dose of charcoal, but further doses should be withheld. Charcoal should not be given to a drowsy patient unless the airway is adequately protected.
      3. Adverse effects
        1. Pulmonary aspiration, especially in drowsy patients.
        2. Administration of charcoal with sorbitol (a cathartic) can cause stomach cramps and vomiting. Repeated doses of sorbitol may cause serious fluid shifts, dehydration, and hypernatremia, especially in young children and elderly persons.
        3. Constipation or intestinal impaction and charcoal bezoar, especially if multiple doses of charcoal are given and the patient is not adequately hydrated.
      4. Technique. (See Table I-37 for guidelines on prehospital and hospital use.)
        1. Give activated charcoal aqueous suspension (without sorbitol), 60-100 g (1 g/kg), orally or by gastric tube.
        2. One or two additional doses of activated charcoal may be given at 1- or 2-hour intervals to ensure adequate gut decontamination, particularly after large ingestions. In rare cases, as many as 8 or 10 repeated doses may be needed to achieve the desired 10:1 ratio of charcoal to poison (eg, after an ingestion of 200 aspirin tablets); in such circumstances, the doses should be given over a period of several hours.
        3. Although charcoal has a neutral taste, some patients refuse to drink it because of its gritty texture and black appearance. Covering the lid and adding charcoal to juice or milk can help facilitate administration.
        4. Some clinicians add a cathartic to hasten the passage of the charcoal through the gastrointestinal tract, even though few data exist to support their efficacy and they can cause adverse effects (eg, fluid loss, electrolyte disturbances). We do not recommend the routine use of a cathartic. When large and/or repeated doses of charcoal are being given (eg, with massive drug ingestions), consider whole bowel irrigation (see below).
    4. Whole-bowel irrigation. Whole-bowel irrigation has become an accepted method for the elimination of some drugs and poisons from the gut. The technique makes use of a surgical bowel-cleansing solution containing a nonabsorbable polyethylene glycol and balanced electrolyte solution that is formulated to pass through the intestinal tract without being absorbed. This solution is given at high flow rates to wash intestinal contents out by sheer volume.
      1. Indications
        1. Large ingestions of iron, lithium, or other drugs poorly adsorbed to activated charcoal.
        2. Large ingestions of sustained-release or enteric-coated tablets containing dangerous drugs.
        3. Ingestion of foreign bodies or drug-filled packets or condoms. Although controversy persists about the optimal gut decontamination for “body stuffers” (persons who hastily ingest drug-containing packets to hide incriminating evidence), prudent management involves several hours of whole-bowel irrigation accompanied by activated charcoal. Follow-up imaging studies may be indicated to search for retained packets if the amount of drug or its packaging is of concern.
      2. Contraindications
        1. Ileus or intestinal obstruction.
        2. Obtunded, comatose, or convulsing patient unless the airway is protected.
      3. Adverse effects
        1. Nausea, diarrhea, and bloating.
        2. Regurgitation and pulmonary aspiration.
        3. Activated charcoal may not be as effective when given with whole-bowel irrigation.
      4. Technique
        1. Administer polyethylene glycol/electrolyte (PEG) bowel preparation solution (eg, CoLyte or GoLytely), 1-2 L/h by gastric tube (children: 500 mL/h or 35 mL/kg/h), until rectal effluent is clear or a total of 10-15 L have been passed. Continued treatment may occasionally be needed (eg, if an x-ray demonstrates the presence of iron tablets remaining in the GI tract).
        2. Some toxicologists recommend the administration of activated charcoal 25-50 g every 2-3 hours while whole-bowel irrigation is proceeding, if the ingested drug is adsorbed by charcoal.
        3. Be prepared for a large-volume stool within 1-2 hours. Bedside commode or placement of a rectal tube is recommended.
        4. Stop administration after 8-10 L (children: 150-200 mL/kg) if no rectal effluent has appeared.
    5. Surgical removal. Occasionally, drug-filled packets or condoms, intact tablets, or tablet concretions persist despite aggressive gastric lavage or whole-gut lavage, and surgical or endoscopic removal may be necessary. Consult a regional poison control center or a medical toxicologist for advice.
TABLE I-35. SOME TOPICAL AGENTS FOR CHEMICAL EXPOSURES TO THE SKINa
Chemical Corrosive AgentTopical Treatment
Hydrofluoric acidCalcium soaks
Oxalic acidCalcium soaks
PhenolMineral oil or other oil; isopropyl alcohol; polyethylene glycol
Phosphorus (white)Copper sulfate 1% (colors embedded granules blue, facilitates mechanical removal)
Potassium permanganateDilute oxalic acid (can remove dermal staining)

aEdelman PA: Chemical and electrical burns. In: Achauer BM, ed. Management of the Burned Patient, (Clinical presentation). Appleton & Lange; 1987.

TABLE I-36. DRUGS AND TOXINS POORLY ADSORBED BY ACTIVATED CHARCOALa
AlkaliHydrocarbons
CyanidebInorganic salts (variable)
Ethanol and other alcoholsIron
Ethylene glycolLithium
FluorideMineral acids
Heavy metals (variable)Potassium

aFew studies have been performed to determine the in vivo adsorption of these and other toxins to activated charcoal. Adsorption may also depend on the specific type and concentration of charcoal.

bCharcoal should still be given because usual doses of charcoal (60-100 g) will adsorb usual lethal ingested doses of cyanide (200-300 mg).

TABLE I-37. GUIDELINES FOR ADMINISTRATION OF ACTIVATED CHARCOAL
General
 The risk of the poisoning justifies the risk of charcoal administration. Activated charcoal can be administered within 60 minutes of the ingestion.a
Prehospital
 The patient is alert and cooperative.
 Activated charcoal without sorbitol is readily available.
 Administration of charcoal will not delay transport to a health care facility.
Hospital
 The patient is alert and cooperative, or the activated charcoal will be given via gastric tube (assuming the airway is intact or protected).

aThe time after ingestion during which charcoal remains an effective decontamination modality has not been established with certainty in clinical trials. For drugs with slow or erratic intestinal absorption, or for those with anticholinergic or opioid effects or other pharmacologic effects that may delay gastric emptying into the small intestine, or for drugs in a modified-release formulation, or after massive ingestions that may produce a tablet mass or bezoar, it is appropriate to administer charcoal more than 60 minutes after ingestion, or even several hours after ingestion.