AGE AS A DECISIVE FACTOR IN GENERAL ANAESTHESIA USE IN PAEDIATRIC PROTON BEAM THERAPY

Proton therapy for paediatric cancer patients is an effective treatment; however, young children have may have difficulties staying still during irradiation.This study investigated the indication of general anaesthesia in paediatric proton therapy. Study setting. This study was a retrospective observational study conducted at the Southern TOHOKU Proton Therapy Center. The system (Mitsubishi Electric Corporation) consists of a synchrotron accelerator, two gantries and one fixed horizontal beamline. Patients and variables. We included paediatric patients (aged 15 years or younger) who underwent PBT at our hospital from April 2016 to December 2018. The patients were referred by the Department of Pediatric Oncology, Fukushima Medical University. Using the database of electronic medical records at our hospital, age, gender, body mass index (BMI), primary disease diagnosis, performance status (PS) (0–4), and details of treatment before PBT (chemotherapy, other radiotherapy, presence or absence of surgery) were extracted for each patient. Regarding treatment, information was extracted on the irradiation site, the irradiation dose, the number of irradiations, the number of irradiation days, and the presence or absence of anaesthesia (general anaesthesia including sedation or no anaesthesia). The median age was 5 years old (range: 1–15), and 13 patients (40.6%) were female. Twelve (37.5%) patients received general anaesthesia. In the general anaesthesia group, airway management using a laryngeal mask was performed in 11 patients (91.6%). Patient age was significantly lower in the general anaesthesia group than in the non-anaesthetised group (p < 0.001). Considering all background factors, only age was strongly associated with anaesthesia in the univariate logistic regression model (odds ratio 0.55 [95% confidence interval 0.35–0.86]; P < 0.01). Thus age is one of the most important factors determining the need for general anaesthesia during proton therapy in children.