Gastric lavage
OVERVIEW
• Gastric lavage is a gastrointestinal decontamination technique that aims to empty the stomach of toxic substances by the sequential administration and aspiration of small volumes of fluid via an orogastric tube.
• previously widely favoured method that has now been all but abandoned due to lack of evidence of efficacy and risk of complications.
INDICATIONS
• Gastric lavage should be rarely, if ever, performed.
• The amount of toxin removed by gastric lavage is unreliable and often negligible, especially if performed after the first hour.
• There are few (if any) situations where the expected benefits of gastric lavage would exceed the risks involved and where administration of activated charcoal would not be provide equal or greater efficacy of decontamination.
TECHNIQUE
• Do not perform in any patient with an impaired level of consciousness unless the airway is protected by a cuffed endotracheal tube
• Position the patient in the left decubitus position with 20° head down
• Measure the length of tube required to reach the stomach externally before beginning the procedure
• Pass a large bore 36-40 G lubricated lavage tube extremely gently down the oesophagus. Stop if any resistance occurs
• Confirm tube position by aspirating gastric contents and auscultating for insufflated air at the stomach; consider CXR for confirmation of position
• Administer a 200 mL aliquot of warm tap water or normal saline into the stomach via the funnel and lavage tube
• Drain the administered fluid into a dependent bucket held adjacent to the bed
• Repeat administration and drainage of fluid aliquots until the effluent is clear
• Activated charcoal 50 g may be administered via the tube once lavage complete.
CONTRAINDICATIONS
• Initial resuscitation incomplete
• Risk assessment indicates good outcome with supportive care and antidote therapy alone
• Unprotected airway where there is a decreased level of consciousness or risk assessment indicates potential for these complications during the procedure
• Small children
• Corrosive ingestion
• Hydrocarbon ingestion
COMPLICATIONS
• Incomplete decontamination leading to severe intoxication despite the procedure
• Pulmonary aspiration
• Hypoxia
• Laryngospasm
• Mechanical injury to the gastrointestinal tract
• Water intoxication (especially in children)
• Hypothermia
• Distraction of staff from resuscitation and supportive care priorities.
EVIDENCE
• most studies are low quality or methodological flawed
• no published data suggests that gastric lavage forces poison into the small bowel
• animal and volunteer studies suggest variable and incomplete return of ingested agents following gastric lavage (generally 1hour in one methodologically flawed study (Kulig et al, 1985)
HISTORICAL PERSPECTIVE
• Gastric lavage was first described in 1822 in London: Jukes’ “exhausting pump” and Bush’s “gastric exhauster”, primarily used for opium ingestion
• The heyday was in the 1950s and 1960s when gastric lavage was the method of choice for all but first aid settings, and for for almost all significant poisonings. At this time barbiturate poisoning was rife and most objective studies took place in this context
• Paediatricians led the way in turning from gastric lavage, due to inherent difficulties in performing the procedure on children
• Position statements from the AACT and thier European counterparts in 1994, 2003 and 2013 have, in essence, recommended that procedure be abandoned
• The procedure is still widely performed in developing countries, including India and Sri Lanka, partly because case fatality rates are higher (10-20% versus 0.5% in the West), other therapeutic options may be unavailable and because of entrenched dogma