Gastric Lavage

Gastric lavage should not be considered one of the routine decontamination methods in toxicology and its use is declining due to various potential complications, scarce evidence, and uncertain clinical effects. While studies in healthy volunteers and animals show decreased absorption of toxins and certain markers, high-quality clinical studies are lacking. We suggest its use exclusively when there is a clear clinical indication for a specific overdose and when there are appropriate supplies, monitoring, and experienced personnel available. As its benefit is limited to very specific circumstances and the risk of iatrogenic injury is very real, in Canada the procedure should be performed at the direction of a poison control specialist or toxicologist.

IndicationsTop

Gastric lavage may be considered within 1 hour of oral intake of a significant amount of a life-threatening toxic substance. It should be restricted to life-threatening exposure in either fully awake and cooperative patients or patients with a protected airway. Examples include recent ingestion of significant amounts of tricyclic antidepressants, labetalol, organophosphates, or toxic alcohols. If available, a local poison control center or toxicologist can provide guidance as to the appropriateness of gastric lavage with or without activated charcoal.

ComplicationsTop

Aspiration, perforation of the gastrointestinal tract, rhythm disturbances, water and electrolyte imbalance.

ContraindicationsTop

Poisoning with corrosives (risk of gastrointestinal perforation); poisoning with volatile substances, hydrocarbons, or detergents (high risk of aspiration); significant risk of gastrointestinal bleeding; unconscious patients (unless intubated); significant psychomotor agitation, patient refusal, lack of cooperation, or resistance.

Patient PreparationTop

The patient should be fully awake and cooperative to perform this procedure; otherwise, the patient’s airway must be secured with endotracheal intubation. Ideally, proactive endotracheal intubation should be done because of the high risk of aspiration and respiratory compromise, either from the procedure or toxic ingestion.

EquipmentTop

Large-bore nasogastric or preferably orogastric tube coated with a lubricant gel (eg, lidocaine gel), funnel, bucket, 50 mL syringe. The size of the tube and its opening must be larger than the pill size.

ProcedureTop

1. Insert the nasogastric/orogastric tube into the stomach, then confirm placement (see Nasogastric/Orogastric Tube Insertion). A fully awake patient should be placed in the left lateral decubitus position. An intubated patient may lie supine.

2. Introduce 200 to 300 mL of water at body temperature into the tube and then lower the tube into the bucket below the level of the stomach before water disappears from the funnel. This will cause the water to return (siphon phenomenon). Repeat until clear (watery) outflow is seen.

3. A single dose of activated charcoal (1 g/kg) can be administered into the stomach after completing gastric lavage as indicated. Exceptions include substances that are not adsorbed by activated charcoal (alcohols, mercury, lead, or iron).

Consider administration of repeated doses of activated charcoal (starting from 1 g/kg and followed by 0.5-1 g/kg every 2-4 hours) in patients who ingested life-threatening doses of quinine, dapsone, phenobarbital, carbamazepine, or theophylline.