Atracurium binds to the cholinergic receptors and blocks the neuromuscular transmission.

It is used in the following situations:

• As an adjunct to general anesthesia
• To facilitate endotracheal intubation
• As a muscle relaxant during surgery and mechanical ventilation in a sedated patient.

Off Label Use of Atracurium in Adults:

• ARDS (Acute respiratory distress syndrome)
• Shivering secondary to therapeutic hypothermia after a cardiac Arrest

Atracurium Dose in Adults

Dose in the treatment of Intensive care unit paralysis (off-label dosing):

• Initial bolus of 0.4 - 0.5 mg/kg intravenous, followed by 4 - 20 mcg/kg/minute (0.24 - 1.2 mg/kg/hour)

Dose in the treatment of Neuromuscular blockade for endotracheal intubation, surgery, or mechanical ventilation (as an adjunct to general anesthesia):

• Intravenous bolus of 0.4 - 0.5 mg/kg initially
• 0.08 to 0.1 mg/kg administered 20 - 45 minutes after the initial dose to maintain neuromuscular block
• A repeat dose at 15 - 25 minute intervals amy be aministered if needed.

Note: Because of the increased risk of hypotension, patients with significant cardiovascular disease may be administered a lower initial dose i.e. 0.3 - 0.4 mg/kg. The dose should also be reduced in asthmatics.

• Initial dose after succinylcholine for intubation (balanced anesthesia):

  • 0.3 - 0.4 mg/kg

• Pre-treatment or priming:

  • 10% of intubating dose (0.04 - 0.05 mg/kg) given 2 - 4 minutes before the larger second dose.

• Maintenance infusion for continued surgical relaxation during extended surgical procedures:

  • A continuous infusion at a rate of 9 - 10 mcg/kg/minute (0.54 - 0.6 mg/kg/hour) may be administered initially.
  • The block usually is maintained by a rate of 5 - 9 mcg/kg/minute (0.3 - 0.54 mg/kg/hour) under balanced anesthesia
  • The usual range is 2 - 15 mcg/kg/minute (0.12 - 0.9 mg/kg/hour)

Atracurium Dose in Childrens

Dose in the treatment of neuromuscular blockade as an adjunct to surgical anesthesia:

• Initial dose in Infants and Children less than 2 years of age:
  • 0.3 - 0.4 mg/kg intravenous (to maintain adequate neuromuscular blockade, additional doses of 0.3 - 0.4 mg/kg may be repeated as needed)
• Initial dose in children older than 2 years and Adolescents:
  • 0.4 - 0.5 mg/kg orally once followed by 0.08 - 0.1 mg/kg 20 - 45 minutes after initial dose to maintain neuromuscular block (the dose may be repeated at 15 - 25 minute intervals as needed)

• Maintenance infusion (for continued surgical relaxation during extended surgical procedures):

  • Infants and Children less than 2 years of age:
    • 6 - 14 mcg/kg/minute as a continuous intravenous infusion (0.4 - 0.8 mg/kg/hour).
  • Children older than 2 years and Adolescents:
    • 9 - 10 mcg/kg/minute intially as a continuous intravenous infusion (0.54 - 0.6 mg/kg/hour)
    • Neuromuscular block is usually maintained by a rate of 5 - 9 mcg/kg/minute (0.3 - 0.54 mg/kg/hour)
    • The usual range is 2 - 15 mcg/kg/minute (0.1 - 0.9 mg/kg/hour)

Dose in the treatment of paralysis in the ICU setting in sedated patients:

• 0.3 - 0.6 mg/kg intravenous as initial bolus, followed by a continuous Intravenous infusion of 5 - 28 mcg/kg/minute (0.3 - 1.7 mg/kg/hour).

Pregnancy Risk Factor C

• When administered during cesarean section, small amounts of the drug have been shown to pass the placental boundary.
• Animal studies have shown adverse fetal events.

Use of Atracurium while breastfeeding

• It is best to avoid breastfeeding while using it.

Atracurium Dose in Renal Disease:

• The manufacturer has not recommended any dose adjustment in patients with renal  disease.

Atracurium Dose in Liver Disease:

• The manufacturer has not recommended any dose adjustment in patients with liver disease.

Side effects :

Frequency not defined.

Mild adverse reactions may be seen secondary to the release of histamine.

Less Common Side Effects of Atracurium Include:

• Cardiovascular:
  • Flushing

Contraindication to Atracurium Include:

• Allergy to atracurium and any component of the formulation
• There is a known allergy to benzyl alcohol.

Warnings and Precautions

• Anaphylaxis
  • It is possible to have severe allergic reactions, including anaphylactic reactions that can lead to death.
  • Epinephrine should always be available in the injection settings to allow immediate use.
  • Patients who have had anaphylactic reactions in the past should be cautious about taking this drug.
• Bradycardia
  • It is possible to develop Bradycardia. It is more common when using atracurium than other neuromuscular blockers.
• Burn injury
  • Atracurium may not be effective for patients with burns greater than 20% of their body surface.
  • After wound healing, resistance to atracurium can persist for many months.
• These conditions may reduce the neuromuscular-blocking effects of atracurium:
  • Respiratory alkalosis
  • Hypercalcemia
  • Demyelinating lesion
  • Peripheral neuropathies
  • Denervation
  • Muscle trauma
• These conditions may increase the neuromuscular blocking effects atracurium.
  • Hypermagnesemia and severe hypocalcemia are examples of electrolyte abnormalities.
  • Neuromuscular diseases
  • Metabolic acidosis
  • Respiratory acidosis
  • Eaton-Lambert syndrome
  • Myasthenia gravis

Atracurium: Drug Interaction

Note: Drug Interaction Categories:

• Risk Factor C: Monitor When Using Combination
• Risk Factor D: Consider Treatment Modification
• Risk Factor X: Avoid Concomitant Use

Monitoring Parameters:

• Vital signs like heart rate, blood pressure, and the respiratory rate.
• Monitor for muscle movements i.e. the degree of muscle paralysis, ventilator asynchrony, and shivering.

How to administer Atracurium?

• You should administer it as an intravenous injection in bolus form.
• Because of tissue irritation, do not give intramuscular injections!
• You can administer it via continuous intravenous injection via an infusion pump. 
• After 24 hours, the preparation or solution should be stopped.

Mechanism of action of Atracurium:

• It blocks neural transmission at a neuromuscular junction through binding to cholinergic receptors sites
• Dose-dependent, the onset of action takes between 2 and 3 minutes.

The peak effect lasts for 3 to 5 minutes. The initial dose of 0.4-0.5 mg/kg under balanced sedation is sufficient to start recovery.

However, it may take up to 60-70 minutes for greater than 95% power to return. Hypothermia patients may experience a longer duration of action. It is subject to ester hydrolysis and Hofmann removal. The metabolites are not active and have no neuromuscular blocking properties. Laudanosine, which acts as a CNS stimulant, is one of the metabolites. It can accumulate over time. 

The liver then converts it to other compounds. The half-life elimination varies with age. It is about 20 minutes in infants, 17 minutes in children, and biphasic in adults (initial 2 minutes and terminal 20 minutes). The drug contains less than 5%ExcretedIn the urine.   

International Brands of Atracurium:

• Acris
• Acrium
• Aculex
• Acurmil
• Atacure
• Atra
• Atracor
• Atradnor
• Atralex
• Atravell
• Atrium
• Farelax
• Genso
• Notrixum
• Relaston
• Relatrac
• Tarcum
• Trac
• Tracrrium
• Tracur
• Tracurix
• Tramus
• Trarium

Atracurium brands in Pakistan: