Mechanically ventilated patients during surgery/in the ICU, neuromuscular blockade

Neuromuscular Blocker Agent, Nondepolarizing

Onset of action (dose dependent): 2 to 3 minutes; Peak effect: 3 to 5 minutes.

Duration: Recovery begins in 20 to 35 minutes following initial dose of 0.4 to 0.5 mg/kg under balanced anesthesia; recovery to 95% of control takes 60 to 70 minutes; hypothermia may prolong the duration of action.

Distribution (Fisher 1990): Vd:
Infants: 0.21 ± 0.12 L/kg.
Children: 0.13 ± 0.04 L/kg.
Adults: 0.1 ± 0.02 L/kg.

Metabolism: Undergoes ester hydrolysis and Hofmann elimination (nonbiologic process independent of kidney, hepatic, or enzymatic function); metabolites have no neuromuscular blocking properties; laudanosine, a product of Hofmann elimination, is a CNS stimulant and can accumulate with prolonged use. Laudanosine is hepatically metabolized.

Half-life elimination:
Infants: 20 ± 5.1 minutes
Children: 17.2 ± 5.1 minutes
Adults: Biphasic: Initial (distribution): 2 minutes; Terminal: 20 minutes.

Excretion: Urine (<5%).
Clearance:
Infants: 7.9 ± 0.2 mL/kg/minute.
Children: 6.8 ± 1.6 mL/kg/minute.
Adults: 5.3 ± 0.9 mL/kg/minute.

Hypersensitivity to atracurium or any component of the formulation; known hypersensitivity to benzyl alcohol (multiple dose vials)
Documentation of allergenic cross-reactivity for neuromuscular blockers is limited. However, because of similarities in chemical structure and/or pharmacologic actions, the possibility of cross-sensitivity cannot be ruled out with certainty.

Small amounts of atracurium have been shown to cross the placenta when given to women during cesarean section.

It is not known if atracurium is present in breast milk. The manufacturer recommends that caution be exercised when administering atracurium to breastfeeding women.

1% to 10%: Cardiovascular: Flushing
<1%, postmarketing, and/or case reports: Bradycardia, bronchospasm, dyspnea, erythema, hypersensitivity reaction, hypotension, increased bronchial secretions, injection site reaction, laryngospasm, pruritus, seizure, tachycardia, urticaria, wheezing

1. Mechanically ventilated patients during surgery, neuromuscular blockade (adjunctive therapy):
Initial: IV: Loading dose of 0.25 to 0.6 mg/kg.
Maintenance:
Intermittent dosing: IV: 0.08 to 0.1 mg/kg every ~15- to 25-minute intervals according to desired clinical response.
Continuous infusion: IV: Initial: 4 to 12 mcg/kg/minute; titrate based on response; usual dosage range: 2 to 15 mcg/kg/minute.

2. Mechanically ventilated patients in the ICU, neuromuscular blockade:
Continuous infusion: IV: Initial: Loading dose of 0.4 to 0.6 mg/kg, followed by continuous infusion of 4 to 12 mcg/kg/minute; adjust rate every ~10 minutes according to desired clinical response and/or peripheral nerve stimulation; usual dosage range: 2 to 20 mcg/kg/minute.
Intermittent dosing: IV: Initial: Loading dose of 0.4 to 0.6 mg/kg, followed by 0.08 to 0.1 mg/kg every ~15 to 25 minutes according to desired clinical response.

ICU paralysis (eg, facilitate mechanical ventilation):
Infants, Children, and Adolescents:
Initial bolus: IV: 0.3 to 0.6 mg/kg/dose; repeat additional doses as needed to maintain desired neuromuscular blockade or begin continuous infusion.
Continuous IV infusion: Initial: 5 to 12 mcg/kg/minute (0.3 to 0.7 mg/kg/hour); range: 5 to 40 mcg/kg/minute (0.3 to 2.4 mg/kg/hour).

Adjunct to surgical anesthesia:
Bolus doses:
Infants and Children >2 years: Initial: IV: 0.3 to 0.4 mg/kg once, followed by additional doses as needed to maintain neuromuscular blockade.
Children ≥2 years and Adolescents: IV: 0.4 to 0.5 mg/kg once as initial dose, then administer 0.08 to 0.1 mg/kg/dose 20 to 45 minutes after the initial dose to maintain neuromuscular blockade; repeat dose every 15 to 25 minutes as needed. Note: Initial dose should be reduced to 0.3 to 0.4 mg/kg in patients with significant cardiovascular disease or with history of increased risk of histamine release (eg, asthma, severe anaphylactoid reaction).
Continuous IV infusion in operating room during extended surgical procedures:
Infants and Children >2 years: Continuous IV infusion: Initial: 6 to 14 mcg/kg/minute (0.4 to 0.8 mg/kg/hour) initiated at the first signs of recovery from initial bolus; titrate until desired neuromuscular blockade is achieved.
Children ≥2 years and Adolescents: Continuous IV infusion: Initial: 9 to 10 mcg/kg/minute (0.5 to 0.6 mg/kg/hour), initiate infusion at initial signs of recovery from bolus dose, titrate until desired neuromuscular blockade is achieved; block is usually maintained by a rate of 5 to 9 mcg/kg/minute (0.3 to 0.5 mg/kg/hour); range: 2 to 15 mcg/kg/minute (0.1 to 0.9 mg/kg/hour).

No dosage adjustment necessary.

No dosage adjustment necessary.

Store at 2-8℃, do not freeze.