Evaluation of effect of sevoflurane or etomidate as induction agent on optic nerve sheath diameter in children patients undergoing strabismus surgery

Objective : Various drugs have been endorsed but no standardised premedication protocol exists to minimize cerebral blood flow effects during intubation. ONSD (Optic Nerve Sheath Diameter) is a noninvasive method to measure intracranial pressure. Sevoflurane and etomidate are two well known induction agents in pediatric patients. This study was designed to evaluate the effect of both drugs on optic nerve sheath diameter in strabismus surgery patients. Methodology : Patients were induced with either Sevoflurane 4-6 % (group S, n=20) or Etomidate 0.2mg/kg (group E; n = 20) inside the operation theatre. The ONSD, haemodynamic response and adverse effects were recorded for 10 min. Results: After intubation HR (Heart rate) increase significantly from baseline values in group S as compared to group E. In group E there was no significant change in HR, MBP (Mean blood pressure) and ONSD. The ONSD in group E was significantly low as compared to group S (p<0.02). There was no significant change in value of HR, MBP and ONSD at 5 and 10 min after intubation. Conclusion: Our findings suggest that etomidate is a preferable agent for induction in strabismus surgeries.