Comparative effects of glycopyrrolate vs. atropine combined with neostigmine on heart rate dynamics and safety outcomes in pediatric patients: a prospective randomized controlled trial.

Background: Neostigmine is a widely used muscle relaxant antagonist that requires combination with anticholinergic agents like atropine to mitigate its muscarinic effects. Glycopyrrolate exerts less influence on cardiac conduction than atropine, making it a preferable option. However, clinical research on its pediatric use is limited. This study aims to compare the effects of glycopyrrolate and atropine, in combination with neostigmine, on heart rate and adverse events in pediatric patients.

Methods: Children undergoing penile flap surgery under general anesthesia combined with a caudal block were randomly assigned to either the glycopyrrolate group (Group G, n = 100) or the atropine group (Group A, n = 100). Postoperatively, patients in Group G received glycopyrrolate (8 µg/kg) and neostigmine (40 µg/kg), while those in Group A received atropine (20 µg/kg) and neostigmine (40 µg/kg) to reverse neuromuscular blockade. The baseline heart rate was defined as the heart rate measured before administering the trial drug, with heart rates recorded every minute thereafter, along with any adverse events noted within 24 h post-operation.

Results: There were no statistically significant differences in age, surgery duration, or baseline heart rates between the two groups (p > 0.05). Heart rate changes within 15 min post-administration were less pronounced in the glycopyrrolate group compared to the atropine group (p < 0.05), indicating reduced fluctuation from baseline. Additionally, the area under the curve (AUC) for heart rate changes in the first 15 min post-administration was lower in the glycopyrrolate group (p < 0.05). No statistically significant differences in adverse events were observed between the two groups (p > 0.05).

Conclusions: Compared to atropine, the combination of glycopyrrolate and neostigmine results in less fluctuation in heart rate but a higher incidence of dry mouth, with no significant differences in other complications. Therefore, glycopyrrolate may be preferred in scenarios where hemodynamic stability is prioritized, considering its higher risk of dry mouth.