The objectives of this study were to investigate the efficacy and dose-effect relationship for glycopyrrolate in the suppression of the oculocardiac reflex, and to compare glycopyrrolate with the reported equivalent dose of atropine. Glycopyrrolate 5 and 7.5ug/kg and atropine 10 and 15ug/kg were studied in 40 paediatric patients to assess more fully the dose of glycopyrrolate required for adequate prevention of the oculocardiac reflex. The results obtained were summarized as follows: 1) The increase in the mean heart rate 5 min after the test drug was statistically significant in all of the four groups. 2) Both drugs showed a dose-related response for reduction in slowing of heart rate after rectus muscle traction. 3) There is great individual variation in response to muscle traction within each group, no group being fully protected from marked slowing in heart rate. 4) The frequency of arrhythmias with low doses of both drugs was more than in high doses with both drugs.
Anesthesia* ; Arrhythmias, Cardiac ; Atropine* ; Child* ; Glycopyrrolate* ; Heart Rate* ; Heart* ; Humans ; Reflex, Oculocardiac ; Traction