Ketamine Tolerance in Children After Repeated Administrations During Radiotherapy Sessions

Ketamine provides a safety zone for sedated but spontaneously ventilated children especially in remote conditions such as radiotherapy units where sedation is an essential practice for children to keep calm and motionless.However, there had been a disagreement about the ketamine doses needed for a continuous and steady level of sedation during repeated radiotherapy sessions in children. In this study, investigators planned to analyse ketamine doses needed and the recovery times in pediatric oncology patients undergoing repeated radiotherapy sessions.After approval from the Baskent University, School of Medicine, Ethics and Research Committee (KA09/247) and informed consents of the patients' guardians, 33 pediatric patients undergoing radiotherapy due to oncologic disorders were enrolled to receive ketamine 2 mg/kg and atropine 10 μg/kg.Patients' demographic data such as age, gender, weight, ASA physical status and duration and total number of radiotherapy sessions were noted. Total ketamine consumption to maintain the targeted sedation level during each session, additional dose administration and the recovery time were recorded. The adverse events such as apnea, laryngospasm, bronchospasm, desaturation, respiratory depression, bradycardia, sedation levels deeper or superficial than intended to, excessive salivation, allergy, nausea and vomiting and need for emergency medication were also noted after each session. The study drugs were prepared, labelled and administered by an anesthetist according to the study protocol and data were recorded by an anesthetist blind to the amount of the study drug used.

Inclusion criteria

• pediatric patients undergoing radiotherapy due to oncologic disorders

Exclusion criteria

• Patients younger than 1 year and older than 14 year,
• patients with cardiac, renal or liver function abnormalities, who were already under sedative drug treatment or allergic to the drugs to be used or the patients for whom the study drugs