Most common conditions that pretreatment drugs utilized:
Infants: Bradycardia
Adults: High BP, Bronchospasm, Increase ICP and Heart Rate
In highly emergent cases it is not worth waiting for pretreatment and can proceed with intubation without waiting for pretreatment.
Fentanyl
Mechanism of Action:
Central-acting opioid agonist used to blunt the sympathetic surge with pain receptor stimulation that occurs with intubation.
Rational:
May be useful in patients where blunting of the sympathetic response is critical
Dose: 2-3 mcg/kg i.v
Pharmacokinetics
Onset: < 1 min
Duration: 30-60 min
Adverse Effects
Respiratory depression
Chest wall rigidity
More common following large doses (eg, >100 μg/kg)
Atropine
Mechanism of Action:
Atropine is used to blunt vagal response by antagonism of muscarinic receptors of the parasympathetic nervous system.
Rational:
The process of intubation can stimulate a strong vagal response in young pediatric patients.
Dose: 0.01-0.02 mg/kg IV
Pharmacokinetics
Onset: 2-16 min
Duration: 30-60 min
Adverse Effects
Tachycardia, dry mouth, flushing, and urinary retention
Lidocaine
Mechanism of Action:
Lidocaine is an amide anesthetic, a class 1B antiarrhythmic, that blocks sodium channels in neurons, eliminating their ability to depolarize and carry signals.
Rational:
In theory, lidocaine is used to suppress the cough reflex which may lead to mitigating ICP elevation during RSI.
Lidocaine may inhibit bronchospasm in patients who have reactive airway disease, induce GABA receptors, suppress other reflexes, and depress the brain stem which leads to mitgation of ICP elevation during RSI.
Dose: 1.5 mg/kg IV
Pharmacokinetics
Onset: 45–90 seconds
Duration: 10–20 minutes
Contraindications
Lidocaine is absolutely contraindicated in patients with an amide anesthetic allergy, severely bradycardic, or who have severe heart block.
