Poisoning, Gastric Decontamination, Emergency Medicine

Basics

Description

- Airway, breathing, and circulation management (ABCs): - Secure airway for decreased mental status/inability to protect airway. - IV access - Cardiac monitor

- With altered mental status from overdose: - Naloxone - Thiamine - Dextrose (or Accu-Chek)

- Activated charcoal: - General: - Prepared by treating heated wood pulp, which creates a large surface area to bind toxins - Mainstay of gastric decontamination - Effective when contents have reached small intestine

- Contraindications: - Caustic ingestions - Unprotected airway - Bowel obstruction or ileus

- Drugs not effectively bound to charcoal: - Metals (borates, bromide, iron, lithium) - Alcohols - Potassium - Potassium cyanide (poorly absorbed) - Hydrocarbons - Caustics

- Indications: - Salicylates - Theophylline - Multiple-dose activated charcoal may decrease area under the curve for drugs such as phenobarbital, phenytoin, and carbamazepine but has not been proven to improve outcome.

- Adverse effects: - Dehydration - Hypermagnesemia - Diarrhea - Abdominal discomfort

- Adverse effects: - Bloating - Rectal irritation - Frequent bowel movements

- Indications: - Currently, rarely performed - Presentation within 1 hr of taking a potentially lethal ingestion with no known antidote - Poisoned intubated patient arriving within ’ Ό1 hr

- Adverse effects: - Intubation of respiratory tree - Esophageal or gastric perforation - Charcoal aspiration - Patient discomfort

- Pediatric considerations: - Avoid in children - Unlikely to result in any clinically significant pill extraction secondary to smaller-bore orogastric tube (i.e., 18F) - Risk of aspiration increased in children - Controversies: Several randomized, controlled trials have documented no benefit when lavage plus activated charcoal is compared with activated charcoal alone.

- Ipecac: - General: - Rarely used - Derived from the roots of the plant Cephaelis acuminata - Exerts emetic action by direct gastric irritation and centrally mediated chemoreceptive trigger-zone stimulation - Delays administration of activated charcoal - Offers no advantage over activated charcoal alone when both treatments are potentially effective

- Dosage: - >12 yr: 30 mL - 1 " 12 yr: 15 mL - 6 mo " 1 yr: 5 " 10 mL + 15 mL clear fluid

Modalities to decontaminate the GI tract of poisons

Treatment

Ipecac is contraindicated in ambulance setting.
Controversies:Home use of ipecac in general is not recommended.In extremely rare cases (e.g., very prolonged transit times, protecting airway), consider ipecac administration only after consultation with regional poison control center.Decreased time to activated charcoal administration when given in pre-hospital setting

Initial Stabilization/Therapy

Airway, breathing, and circulation management (ABCs):Secure airway for decreased mental status/inability to protect airway.IV accessCardiac monitor
With altered mental status from overdose:NaloxoneThiamineDextrose (or Accu-Chek)

Ed Treatment/Procedures

Activated charcoal:General:Prepared by treating heated wood pulp, which creates a large surface area to bind toxinsMainstay of gastric decontaminationEffective when contents have reached small intestineDose:1 " 2 g/kg of body weight or an activated charcoal-to-drug ratio of 10:1; often mixed with sorbitol (see below)Oral or nasogastric tube administrationIndications:Administer in every toxic ingestion (see below for exceptions).Optimal for toxic ingestions presenting within 1 hr of ingesting a drug that is absorbed by charcoal in a patient with a patent airwayAdverse effects:Vomiting and constipationCharcoal aspiration and subsequent charcoal pneumonitisContraindications:Caustic ingestionsUnprotected airwayBowel obstruction or ileusDrugs not effectively bound to charcoal:Metals (borates, bromide, iron, lithium)AlcoholsPotassiumPotassium cyanide (poorly absorbed)HydrocarbonsCausticsPediatric considerations:Mix with palatable substance (cola or juice) to facilitate intake or administer via gastric tube.Controversies:Randomized, controlled trials have shown a slightly worse outcome and higher complication rate when asymptomatic patients received charcoal vs. nothing.An extremely small minority of patients are likely to benefit from gastric lavage.
Multiple-dose activated charcoal:General:Used in toxic ingestions that are well absorbed by charcoal and undergo enterohepatic circulationDose:1 g/kg followed by 0.5 g/kg q2 " 6hNever use cathartics in conjunction with multiple-dose activated charcoal.Indications:SalicylatesTheophyllineMultiple-dose activated charcoal may decrease area under the curve for drugs such as phenobarbital, phenytoin, and carbamazepine but has not been proven to improve outcome.
Cathartics:General:Used in combination with activated charcoal to prevent constipation and to enhance GI transit timeLimited data available to demonstrate any decreased absorption when a cathartic (sorbitol) is added to activated charcoalCathartics alone are of no proven benefit and should be avoided.Never use cathartics in conjunction with multiple-dose activated charcoal.Dose:Magnesium citrate: 10% solution: 250 mL (peds: 4 mL/kg)Magnesium sulfate: 15 " 20 g (peds: 250 mg/kg)Sorbitol: 0.5 " 1 g/kg to a max. 100 g of 70% solution (peds: >1 yr old: 0.5 " 1 g/kg as a 35% solution to a max. 50 g) PO mixed in the activated charcoal slurry " use only in 1st dose.Adverse effects:DehydrationHypermagnesemiaDiarrheaAbdominal discomfortContraindications:Pre-existing dehydrationRenal disease (cathartics containing magnesium)Avoid in childrenControversies:No proven benefit and some cases of harm reported
Whole-bowel irrigation:General: Cleansing of bowelIndications:Toxins not well absorbed by charcoal, such as toxic iron and lithium ingestionsToxins in sealed containers (body packers) without signs of GI perforationToxic, sustained-release product ingestionsDose:Polyethylene glycol (Colyte, GoLytely)Solution at 2 L/hr in adults (0.5 L/hr in children) until rectal excretions clearAdminister via nasogastric tube with activated charcoal via continuous or bolus method as indicated.Adverse effects:BloatingRectal irritationFrequent bowel movementsContraindications:Mechanical or pharmacologic ileusBowel obstructionHypotensionIntestinal perforationUnprotected airway
Orogastric lavage:General:Placement of large-bore tube (32F " 36F) in stomach for removal of ingested toxinsEffectiveness of orogastric lavage depends on time since ingestion, timing of last meal, and toxin ingested.Protected airway is essential prior to any attempts at orogastric lavage.Indications:Currently, rarely performedPresentation within 1 hr of taking a potentially lethal ingestion with no known antidotePoisoned intubated patient arriving within ’ Ό1 hrAdverse effects:Intubation of respiratory treeEsophageal or gastric perforationCharcoal aspirationPatient discomfortContraindications:Large pills (limited by lavage-tube port size) ingestionCaustics (acids and alkali) ingestionHydrocarbon ingestionIngestion of agents that rapidly depress mental statusUnprotected airwayPediatric considerations:Avoid in childrenUnlikely to result in any clinically significant pill extraction secondary to smaller-bore orogastric tube (i.e., 18F)Risk of aspiration increased in childrenControversies: Several randomized, controlled trials have documented no benefit when lavage plus activated charcoal is compared with activated charcoal alone.
Ipecac:General:Rarely usedDerived from the roots of the plant Cephaelis acuminataExerts emetic action by direct gastric irritation and centrally mediated chemoreceptive trigger-zone stimulationDelays administration of activated charcoalOffers no advantage over activated charcoal alone when both treatments are potentially effectiveDosage:>12 yr: 30 mL1 " 12 yr: 15 mL6 mo " 1 yr: 5 " 10 mL + 15 mL clear fluidIndications:Adverse effects:Vomiting may complicate and worsen clinical presentation.Delay to administration of activated charcoal or oral antidotesContraindications:Caustics (acids and alkali) ingestionHydrocarbon ingestionIngestion of agents that rapidly depress mental statusPatient actively vomiting

Pearls and Pitfalls

Ipecac has no utility in the ED.
Administer activated charcoal in almost every toxic ingestion that presents within 1 hr with a patent airway
Never use multiple doses of cathartic in conjunction with multiple-dose activated charcoal.

Additional Reading

Albertson TE, Owen KP, Sutter ME, et al. Gastrointestinal decontamination in the acutely poisoned patient. Int J Emerg Med. 2011;4:65.
Holstege CP, Dopmeier SG, Bechtel LK. Critical Care Toxicology Emergency Medicine Clinics of North America " Volume 26, Issue 3 (August 2008).
Isbister GK, Kumar VV. Indications for single-dose activated charcoal administration in acute overdose. Curr Opin Crit Care. 2011;17(4):351 " 357.

Codes

ICD9

977.9 Poisoning by unspecified drug or medicinal substance

ICD10

T65.91XA Toxic effect of unspecified substance, accidental (unintentional), initial encounter

SNOMED

75478009 Poisoning (disorder)
235453002 selective decontamination of the digestive tract (procedure)