What is the recommended dose of Sugammadex (Bridion) for a newborn weighing 3.3kg requiring reversal of neuromuscular blockade?

Sugammadex Dosing in a 3.3kg Newborn

Sugammadex is not recommended for use in newborns, as it had not received marketing approval for children under 2 years of age as of the most recent guidelines, and there is insufficient safety and efficacy data in this population. 1

Critical Age-Related Contraindication

• As of 2018, sugammadex had not yet been granted marketing approval for children under 2 years of age, making its use in a 3.3kg newborn off-label and not supported by current guidelines 1
• The most recent pediatric study demonstrating sugammadex safety and efficacy only included children aged 2 to <17 years, explicitly excluding neonates and infants 2

Alternative Reversal Strategy for Neonates

For reversal of rocuronium-induced neuromuscular blockade in this newborn, neostigmine remains the standard approach:

• Neostigmine 0.04-0.05 mg/kg (approximately 0.13-0.17 mg for a 3.3kg infant) combined with atropine 0.02 mg/kg (approximately 0.066 mg for a 3.3kg infant) 1, 3
• Administer only when at least 4 responses to train-of-four (TOF) stimulation are present 1
• Expect reversal to TOF ratio ≥0.9 in 10-20 minutes 1
• Quantitative neuromuscular monitoring is essential in pediatric patients, as residual neuromuscular blockade occurs in 28% of children receiving muscle relaxants 1, 4

Clinical Context for Muscle Relaxant Use in Newborns

• For rapid sequence induction in newborns (<1 month), succinylcholine 1.8 mg/kg is the first-line muscle relaxant (GRADE 1+) 1, 5, 4
• Rocuronium >0.9 mg/kg is the alternative when succinylcholine is contraindicated 1, 5, 4
• The duration of apnea without hypoxemia is significantly shorter in newborns, necessitating rapid airway protection 1, 4

Critical Safety Considerations

• Never use succinylcholine in newborns with neuromuscular diseases due to risk of rhabdomyolysis or life-threatening hyperkalemia 1, 4
• Muscle relaxants during inhaled induction in infants have documented benefits for intubation conditions and reduced respiratory events 1, 4
• The allergic risk with muscle relaxants in pediatric populations is low but incompletely characterized 1, 4

Why Sugammadex Data Cannot Be Extrapolated to Newborns

• Sugammadex dosing is based on body weight, but neonates have different pharmacokinetic and pharmacodynamic profiles than older children 2
• In obese patients, sugammadex dosing is adjusted to ideal body weight rather than actual body weight, demonstrating that simple weight-based dosing is not universally applicable 1
• The youngest patients studied in randomized trials were 2 years old, leaving a critical evidence gap for neonates 2

If Sugammadex Were Hypothetically Used (Off-Label)

If clinicians were to use sugammadex off-label in this scenario despite lack of approval, the theoretical dosing would be:

• For moderate neuromuscular blockade (2-4 TOF responses): 2 mg/kg = 6.6 mg 1, 2
• For deep neuromuscular blockade (PTC 1-5): 4 mg/kg = 13.2 mg 1, 2, 6
• Continue quantitative neuromuscular monitoring after administration to detect possible recurrence of blockade 1
• Recurrent neuromuscular blockade has been documented with lower sugammadex doses, particularly with rocuronium 6

However, this off-label use cannot be recommended given the absence of safety data in neonates and lack of regulatory approval for this age group. 1, 2