Gastric Lavage and Activated Charcoal Application

by Elif Dilek Cakal

Case Presentation

A 22-year old female presented to the emergency department 15 minutes after she had committed suicide by taking 30 pills of 500 mg acetaminophen. She had no known chronic diseases. Her blood pressure was 134/87 mmHg; temperature, 36.4°C; heart rate of 70 bpm and regular; respiration 15 bpm; and O2 saturation 99%. At the time of arrival, she was asymptomatic. Nothing was remarkable on examination. Gastric lavage was performed. 1 mg/kg of activated charcoal was given to the patient. IV N-acetylcysteine treatment was started. She was admitted to the hospital.

Gastric Lavage Procedure

Emergency Indications

Gastric Lavage (GL) should not be undertaken routinely. Whether gastric lavage positively alters the morbidity or mortality of the poisoned patient, even applied shortly after the intake, is controversial. GL is indicated only if:

Oral intake < 60 minutes
The life-threatening dose of the toxic substance is ingested

Contraindications

Patients with compromised airway reflexes, unless they are intubated. If the critical situation of the patient indicates intubation, then, gastric lavage may be performed. Intubation, only for decontamination, is not recommended.
Non-toxic or non-life-threatening intoxications.
Hydrocarbons intake (unless containing highly toxic substances such as pesticides).
Oral intake of caustic substances.
Poisonings with toxic substances; those are more toxic to lungs than to gastrointestinal system.
Poisonings with pills that are known not to fit through the holes of the gastric tube
Known esophageal structures.
History of gastric bypass surgery.

Emergency Physician (EP) must be cautious in combative patients and patients with medical conditions such as bleeding disorders.

Equipment and Patient Preparation

Equipment for GL includes:

Intravenous access and monitoring
A large suction catheter
Local analgesics and lubricants
Intubation equipment
Sedatives (if necessary)
Restraints (if necessary)
Bite block or oral airway
Oral or nasogastric tubes
- 36- to 40-French or 30 English-gauge tubes in adults (oral)
- 24- to 28- French-gauge in children (oral)
Lavage systems
- Commercially available
- Intermittent aliquots of lavage fluid can be given and withdrawn manually
Activated charcoal (see below)
Normal saline or water

Before starting, the steps of the procedure must be explained to patients in an attempt to gain cooperation. If the patient is too agitated, sedatives in anxiolytic doses may be used. EP must keep in mind that significantly altered level of consciousness due to sedation warrants intubation.

Although there is no adequate data in humans to show that tube diameter or route is important, the oral route is primarily preferred for the gastric lavage. Nasogastric tubes are less traumatic for patients and are preferred in liquid ingestions and children.

Place all patients in the left lateral decubitus position in Trendelenburg to facilitate the content removal and to decrease the aspiration risk. Supine position greatly increases aspiration risk, unless the patient is intubated.

The tube must be measured from the corner of the mouth to the mid-epigastrium in order to avoid kinking and complications.

Procedure Steps

A video explaining the steps of the insertion of the gastric tube

Explain the procedure to the patient.
Collect the equipment and place the patient in the left lateral decubitus position.
Put a bite block or oral airway into the patient’s mouth.
Introduce to pass the tube gently
When the pharynx is reached, put the patient’s chin on the chest to facilitate passage of the tube into the esophagus.
Confirm the placement
Aspirate and remove the gastric contents before gastric irrigation
Repeatedly introduce 200–300 mL of lavage solution (10 mL/kg body weight in children up to a maximum of 300 mL) into the stomach and then remove them
Continue lavage until the fluid becomes clear
Administer activated charcoal via tube
Clamp off and remove the tube

Hints and Pitfalls

The procedure is intended to be therapeutic, not punitive.
In some situations, Gastric lavage may be helpful for up to 2 hours:
- Highly toxic drugs
- Drugs not absorbed by activated charcoal
- Sustained release or enteric-coated products
Auscultation of the stomach generally confirms the placement of the tube during injection of air with a 50-mL syringe and aspiration of gastric contents. Radiographic confirmation should be considered, especially in children and intubated patients.
A cough, stridor, or cyanosis indicates that the tube has entered the trachea; withdraw the tube immediately and reattempt passage.

Post Procedure Care and Recommendations

For most patients, a short period of observation of vital signs is adequate.
The nature of the poisoning will lead the management.

Complications

GL is generally safe but not harmless.

Complications of GL include:

Misplacement of the gastric tube into the trachea.
Pulmonary aspiration of gastric content of lavage fluid, especially in patients with compromised airway reflexes.
Aspiration pneumonia.
Laryngospasm and hypoxia, especially in patients with lung diseases.
Esophageal lacerations or perforation.
Gastric perforation.
Fluid and electrolyte disturbances, especially in children.
Hypothermia.
Nasal, oral, pharyngeal, pyriform sinus injuries.
Pulmonary hemorrhage, pneumothorax, and empyema.

Pediatric, Geriatric, and Pregnant Patient Considerations

Gastric lavage is always a difficult procedure to apply to children. Nasogastric tubes may be preferred. 10 mL/kg aliquots of lavage solution up to a maximum of 300 mL is given and removed. Because electrolyte disturbance has occurred in children who were lavage with tap water, prewarmed (45°C) normal saline is generally recommended for children.
Elderly patients are susceptible to cardiac consequences of both procedure and the poisoning; therefore, their vital signs should be monitored closely.
Gastric lavage and activated charcoal are considered safe for pregnant patients. Poisonings that are toxic to the fetus as well as toxic to mother must be considered.

Activated Charcoal Application

Emergency Indications

Oral intake < 60 minutes
the life-threatening dose of the toxic substance

Multi-Dose Activated Charcoal (MDAC) Indications

Life-Threatening Oral Intake of
- Carbamazepine
- Dapsone
- Phenobarbital
- Quinine
- Theophylline