Evaluation of propofol for repeated prolonged deep sedation in children undergoing proton radiation therapy

Background: The aim of this study is to evaluate the safety and sufficiencyof a fixed dose rate propofol infusion for repeated prolongeddeep sedation in children for proton radiation therapy (PRT). Methods: With ERB approval, we recorded anaesthesia monitoring data inchildren undergoing repeated prolonged propofol sedation forPRT. Sedation was introduced with a single bolus of i.v. midazolam0.1 mg kg^–1 followed by repeated small boluses of propofoluntil sufficient depth of sedation was obtained. Sedation wasmaintained with fixed dose rate propofol infusion of 10 mg kg^–1h^–1 in all patients up to the end of the radiation procedure.Patient characteristics, number and duration of sedation, propofolinduction dose, necessity to alter propofol infusion rate, andheart rate, mean arterial pressure, respiratory rate were notedat the end of the radiation procedure before cessation of thepropofol infusion. Data are mean (SD) or range (median) as appropriate. Results: Eighteen children aged from 1.4 to 4.2 yr (2.6 yr) had 27.6(SD 2.0) (497 in total) radiation procedures within 44.1 (4.0)days lasting 55.7 (8.8) min. Propofol bolus dose for induction,monitoring, and positioning was 3.7 (1.0) mg kg^–1. Propofolbolus requirements were quite stable over the successive weeksof treatment and variability was larger between individualsthan over time. In none of the children did propofol infusionrate need to be changed from the pre-set 10 mg kg^–1 h^–1flow rate because of haemodynamic state, respiratory conditionsor inadequate anaesthesia. Conclusions: Repeated prolonged deep sedation over several weeks in veryyoung children using a fixed rate propofol infusion was safeand adequate for all patients.