Gastric Lavage · What Is It and How It Is Done

This procedure can be used for evaluating gastrointestinal (GI) bleeds; however, it is used primarily for GI decontamination in a potentially toxic and life-threatening situation, such as ingestion of poisons or drug overdose. These substances may include central nervous system depressants, like opioids; phencyclidine (PCP); acetaminophen (paracetamol); paralytic shellfish poison; and heavy metals. Gastric lavage may be used in other situations, including collecting specimens for diagnostic purposes or in cases of children under 12 years old with suspected pulmonary tuberculosis. To be effective, gastric lavage may be attempted soon after intake of the substance; typically, less than an hour since ingestion is ideal.

The safety and efficacy of gastric lavage for gastrointestinal decontamination are under debate for all individuals, but especially in children. Drawbacks of this procedure include the potential for incomplete content removal; the invasive, painful, and time-consuming nature of the procedure; and the risk of complications, such as bradycardia, esophageal or gastric perforation, aspiration pneumonia, hypoxia, electrolyte imbalances, and other iatrogenic damage. For these reasons, the American Academy of Clinical Toxicology (AACT) and the European Association of Poison Centres and Clinical Toxicologists (EAPCCT) currently recommend against the use of gastric lavage for the routine treatment of poisoning. When performed in rare and selective cases, it is advised to be conducted by properly trained and expert individuals. 

Nonetheless, gastric lavage is often considered when the poisoning cannot be managed with other less invasive decontamination, elimination, or antidotal therapies. Activated charcoal, for example, is an oral suspension that can adsorb many ingested toxins through direct contact. It can be used instead of gastric lavage since it’s often safer and more effective. In some cases, it can even be combined with gastric lavage for an additional benefit. If the ingested toxic substance has an antidote (e.g., naloxone for opioid overdose or acetylcysteine for acetaminophen toxicity), the antidote is typically the treatment of choice. In other cases, whole-bowel irrigation may be necessary. In this approach, an osmotically balanced solution containing a substance called polyethylene glycol is administered orally or through a nasogastric tube to reduce the toxin’s absorption and induce liquid stool. 

Gastric lavage may be contraindicated in individuals at risk of gastrointestinal hemorrhages, such as those with coagulopathies or after surgery; in cases of caustic ingestion (i.e., ingestion of strongly acidic or alkaline substances); or when the airway is unprotected, such as when essential reflexes are lost, and no endotracheal intubation was performed beforehand. 

Gastric lavage can be done when the individual is awake and fully cooperative or under general anesthesia. In cases of decreased level of consciousness or high risk of airway compromise during the procedure, rapid anesthesia and tracheal intubation (i.e., rapid sequence induction) are typically done. 

Due to the risk of aspiration resulting from vomiting, the individual may be placed in a lateral decubitus (i.e., lying on the side) and Trendelenburg position (i.e., with the head slightly lowered). Before placing the orogastric tube, an oral airway or a bite block is positioned in the mouth to prevent biting the tube. The pharynx is sprayed with local anesthesia, and the tube is carefully placed, avoiding damage to the posterior pharynx and esophagus. The proper placement of the tube is then ensured by introducing air into the tube while auscultating the stomach or using an X-ray, in some cases. For a final check, aspiration is attempted. If gastric contents are confirmed, the lavage begins with sequential instilling of fluid (e.g., water or normal saline) and aspiration of the fluid and gastric contents. If resistance occurs during aspiration, there may be an increased risk of mucosal lining perforation, and gravity, instead of aspiration, may be used to drain the remaining lavage fluid.