Background: The oculocardiac reflex (OCR) is frequently observed during strabismus surgery. This study was designed to evaluate and compare the effect of sevoflurane and desflurane on the incidence of OCR.
Methods: After obtaining Institutional Review Board approval and informed consent from parents, we enrolled 237 paediatric patients, aged 2-10 yr, undergoing strabismus surgery. No premedication was given. Anaesthesia was induced with thiopental and rocuronium. Patients were randomly allocated to one of the two anaesthetic regimens. Group S (n = 123) received sevoflurane and Group D (n = 114) received desflurane, both with 60% N2O/O2 for maintenance of anaesthesia. The OCR was defined as a > or = 20% decrease in heart rate (HR) from baseline values obtained immediately before muscle manipulation. If the HR did not increase after release of muscle tension, atropine 0.01 mg kg(-1) was administered.
Results: There were no significant differences between the two groups in age, sex, body weight, and the number of muscles operated upon. The mean values of baseline HR were 123 (16) min(-1) in Group S and 121 (18) in Group D (NS). The minimum HR was 106 (22) min(-1) in Group S and 103 (21) in Group D (NS). There was no difference in the incidence of OCR between sevoflurane (26.0%) and desflurane (28.0%) anaesthesia.
Conclusions: Both agents can be used safely during strabismus surgery in paediatric patients.