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Decontamination of Patients After Oral Exposure to Toxicants 1087

Decontamination of Patients After Oral Exposure to Toxicants Client Education
Sheet
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pre-existing conditions of the patient that can
Difficulty level: ♦
lb body weight) PO, maximum 45 mL
cause vomiting to be hazardous, including first and then give 2.2 mL/kg (1 mL/
Overview and Goal severe cardiac disease (vomiting is a strong (3 tablespoons) by cheek pouch using
These procedures are used to prevent or lessen vagal influence, and pre-existing bradycardia, spoon, medicine cup, turkey baster, or
the severity of clinical signs that may develop such as the sick sinus syndrome, may be oral syringe. Once given, encourage gentle
after ingestion of a toxicant. exacerbated), seizure disorder, or recent exercise, such as on-leash walking. The
abdominal surgery. patient normally vomits within 15-20
Indications • Emesis may not be needed if the animal minutes (>90% of cases). If not, can
• Emetics and gastric lavage are used for remov- has already vomited and is not appropriate repeat once, or
ing a toxicant from the gastrointestinal (GI) if the animal is already exhibiting clinical ○ Dogs: apomorphine 0.03 mg/kg IV
tract. signs such as ataxia, disorientation, coma, or 0.04 mg/kg IM (least preferred) or Procedures and Techniques
• Dilution is indicated when an irritating (e.g., seizures, or recumbency, which make emesis crush 1 4 - 1 2 tablet, place in a syringe
some detergents, bleaches) or corrosive (e.g., hazardous. (without a needle), dissolve with a few
alkali, acids) material has been ingested. • Obtain a baseline serum sodium concentra- drops of saline, and administer into the
• Activated charcoal is used for binding tion before administering activated charcoal conjunctival sac. After sufficient vomiting
(adsorbing) a toxicant in the GI tract to due to risk of developing hypernatremia (an occurs, rinse conjunctival sac. Sedation
prevent systemic absorption and facilitate uncommon but serious idiosyncratic reaction can be reversed with naloxone 0.04 mg/
removal in the feces. seen in some dogs). kg IV if needed.
○ Cats: xylazine 0.44 mg/kg IM (reverse
Contraindications Possible Complications and with yohimbine 0.1-0.25 mg/kg slow IV
• Animals that are able to vomit safely include Common Errors to Avoid after vomiting is complete) or dexmedeto-
dogs, cats, ferrets, and potbelly pigs. Emetics • Dilution: using an excessive volume can lead midine 40 mcg/kg IM (reverse with equal
should not be used in birds, rodents, rabbits, to vomiting and re-exposure of the esophagus volume of atipamezole)
horses, or ruminants. to the damaging material. • Gastric lavage (p. 1117): The patient is
• If the patient has ingested a central nervous • Emesis: if too much 3% hydrogen peroxide is anesthetized unless already comatose; a
system stimulant and is already agitated, the used or more concentrated hydrogen peroxide cuffed endotracheal tube must be in place
additional stimulation of vomiting could (>3%) is used, protracted or hemorrhagic to prevent aspiration
trigger seizures. gastritis can result. ○ A large-bore orogastric tube with a
• Induction of vomiting and gastric lavage are • Gastric lavage: risks associated with gastric fenestrated end is inserted to a length
contraindicated with lavage include esophageal or gastric damage equal to the distance from the nose to
○ Ingestion of corrosive agents, including or perforation, hypothermia and accidental the xiphoid cartilage. Placement of the
alkalis and acids, due to esophageal and placement of the tube in the trachea and orogastric tube must be accurate to avoid
oral damage instillation of fluid into the lungs. The tube infusion of water into the respiratory tract
○ Ingestion of petroleum distillates (volatile should be well lubricated, advanced gently (fatal).
hydrocarbons) due to the risk of aspiration without encountering resistance, and checked ○ Body temperature (38°C; always < 40°C
• Dilution is not appropriate in patients repeatedly to ensure it is in the esophagus and > 35°C) tap water (5-10 mL/kg) is
who are at an increased risk for aspiration, and stomach before administering any liquid instilled. The head of the patient should
including those who are actively seizing or or solution into the tube. be kept lower than the chest throughout
obtunded. • Activated charcoal the procedure.
• Activated charcoal does not bind all toxicants. ○ Risk of aspiration if regurgitation or ○ Gravity is used to instill the water (by
Some chemicals that are not bound effectively vomiting occurs after giving charcoal. If a holding the tube higher than the patient)
by charcoal include ethanol, methanol, patient does aspirate charcoal, the prognosis and then to drain the water and gastric
fertilizer, fluoride, petroleum distillates, is poor. Pretreatment with an antiemetic contents by moving the tube to be lower
most heavy metals, iodides, nitrates, nitrites, can reduce the risk of aspiration. than the patient.
sodium chloride, and chlorate. ○ If the activated charcoal is retained in the ○ The flushing process should be repeated
• Activated charcoal should not be given GI tract for an extensive period (e.g., due multiple times until the lavage fluid runs
to animals that are actively vomiting or to ileus), it may release the compound it clear. With each flush, approximately
those that have ingested caustic or corrosive had adsorbed, leading to clinical signs. For the same amount of fluid instilled
materials. this reason, activated charcoal products should be removed. The free end of
frequently also contain a cathartic. the tube should be occluded before
Equipment, Anesthesia ○ Hypernatremia may occur due to an tube removal to reduce the risk of
Unless the patient is already obtunded, gastric osmotic shift of water from the intracel- aspiration.
lavage usually requires sedation or general lular and extracellular spaces into the GI • Activated charcoal 1-2 g/kg PO (use labeled
anesthesia. tract as a result of the activated charcoal dosage when using commercial products)
solution. ○ If asymptomatic: can be given with a large
Anticipated Time (35-60 mL) oral dosing syringe or can be
The time varies depending on the procedure Procedure mixed with a small amount of canned
(see Procedure below). • Dilution: give a small amount (2-6 mL/kg food or chicken broth and offered to the
in dogs, cats) of water, milk, or canned food patient.
Preparation: Important orally. ○ In symptomatic patients, it is administered
Checkpoints • Emetics by orogastric tube (general anesthesia if
• When deciding whether to induce emesis, ○ Dogs: 3% hydrogen peroxide solution not comatose; a cuffed endotracheal tube
the clinician must take into account any (over the counter): feed a small meal is essential before passing orogastric tube).

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