Which reversal agent is associated with fetal bradycardia due to placental transfer when reversing anesthesia in pregnancy?

Which reversal agent is associated with fetal bradycardia due to placental transfer when reversing anesthesia in pregnancy?

• A. Neostigmine
• B. Glycopyrrolate
• C. Atropine
• D. Sugammadex

Answer: (A)

When reversing neuromuscular blockade in pregnancy, placental transfer of the reversal drug matters for the fetus. Neostigmine inhibits acetylcholinesterase, which raises acetylcholine levels. If this increases acetylcholine reaches the fetal circulation, it can stimulate fetal muscarinic receptors and slow the fetal heart, causing bradycardia. That’s why clinicians often give an antimuscarinic, such as glycopyrrolate, with neostigmine to blunt these effects and reduce fetal exposure. In contrast, atropine crosses the placenta more readily and can cause different fetal effects, while sugammadex reverses the block without increasing acetylcholine and generally has less placental transfer. Thus, the reversal agent most associated with fetal bradycardia due to placental transfer is neostigmine.

When reversing neuromuscular blockade in pregnancy, placental transfer of the reversal drug matters for the fetus. Neostigmine inhibits acetylcholinesterase, which raises acetylcholine levels. If this increases acetylcholine reaches the fetal circulation, it can stimulate fetal muscarinic receptors and slow the fetal heart, causing bradycardia. That’s why clinicians often give an antimuscarinic, such as glycopyrrolate, with neostigmine to blunt these effects and reduce fetal exposure. In contrast, atropine crosses the placenta more readily and can cause different fetal effects, while sugammadex reverses the block without increasing acetylcholine and generally has less placental transfer. Thus, the reversal agent most associated with fetal bradycardia due to placental transfer is neostigmine.