Gastric lavage is an emergency medical procedure used to remove toxic substances from the stomach after ingestion.
It involves inserting a large-bore orogastric tube into the stomach, followed by repeated instillation and aspiration of water or saline to flush out the stomach contents.
Indications:
- Recent ingestion of a potentially life-threatening substance: Gastric lavage is generally considered within the first 1-2 hours after ingestion when a patient has ingested a large or potentially fatal dose of a toxin.
- Substances that do not adsorb well to activated charcoal: Some substances (e.g., lithium, iron) may not be well adsorbed by activated charcoal, and lavage might be considered in certain cases.
Contraindications:
- Caustic or corrosive ingestion: Lavage is contraindicated in cases where the ingestion of caustic substances (e.g., acids, alkalis) could cause further injury to the esophagus or stomach during the procedure.
- Ingestion of hydrocarbons: Hydrocarbon ingestion (e.g., gasoline, kerosene) poses a high risk of aspiration during lavage, so it is contraindicated.
- Unprotected airway: Lavage is not indicated in patients with decreased levels of consciousness unless the airway is protected (e.g., through intubation).
Risks:
- Aspiration: If the patient vomits during the procedure or if lavage is performed improperly, there is a risk of aspiration, leading to chemical pneumonitis or other respiratory complications.
- Esophageal or gastric perforation: This is rare but can occur, especially in patients with underlying gastrointestinal pathology.
- Electrolyte imbalance: If lavage is performed with large amounts of water or saline, there is a risk of electrolyte disturbances.
Effectiveness:
Gastric lavage’s effectiveness decreases significantly after the first hour post-ingestion, as most substances may have passed beyond the stomach by that time. It is generally not recommended as a first-line treatment for most poisonings, with exceptions in cases of massive ingestion of highly toxic substances.
Current Role in Toxicology:
Due to the availability of more effective and safer interventions (e.g., activated charcoal), gastric lavage is rarely performed in modern medical practice. It is now only considered in specific, severe cases where the benefits outweigh the risks.
