Gastric lavage

Gastric lavage, also commonly called Stomach pump or Gastric irrigation, is the process of cleaning out the contents of the stomach. It has been used for over 200 years as a means of eliminating poisons from the stomach. Such devices are normally used on a person who has ingested a poison or overdosed on a drug. They may also be used prior to surgery, to clear the contents of the digestive tract before it is opened.

Technique
Gastric lavage involves the passage of a tube via the mouth or nose down into the stomach, followed by sequential administration and removal of small volumes of liquid. The placement of the tube in the stomach must be confirmed either by air insufflation while listening to the stomach, or by pH testing a small amount of aspirated stomach contents. This is to ensure the tube is not in the lungs. In adults, small amounts of warm water or saline are administered and via a siphoning action removed again. In children, normal saline is used as children are more at risk of developing hyponatremia if lavaged with water. Because of the possibility of vomiting, a suction device is always on hand in case of aspiration of stomach contents. Lavage is repeated until the returning fluid shows no further gastric contents. If the patient is unconscious or cannot protect their airway then the patient should be intubated before performing lavage.

Indications
Gastric lavage is used infrequently in modern poisonings and some authorities have suggested that it not be used routinely, if ever, in poisoning situations. Lavage should only be considered if the amount of poison ingested is potentially life-threatening and the procedure can be performed within 60 minutes of ingestion.

Contraindications
Lavage is contraindicated when patients have a compromised, unprotected airway and in patients at risk of gatrointestinal hemorrhage or perforation. Relative contraindications include when the poisoning is due to a corrosive substance, hydrocarbons , or for poisons that have an effective antidote.

Complications
Many complications have been reported although it appears serious complications are uncommon. The most dangerous risk is aspiration pneumonia, this is more likely to occur if hydrocarbons are ingested or in patients without a protected airway. Other complications include laryngospasm, hypoxia, bradycardia, epistaxis, hyponatremia, hypochloremia, water intoxication, or mechanical injury to the stomach.