Effect of Repeated Exposure to Sevoflurane on Electroencephalographic Alpha Oscillation in Pediatric Patients Undergoing Radiation Therapy: A Prospective Observational Study

BACKGROUND

Pharmacological tolerance is defined as a decrease in the effect of a drug over time, or the need to increase the dose to achieve the same effect. It has not been established whether repeated exposure to sevoflurane induces tolerance in children.

METHODS

We conducted an observational study in children younger than 6 years of age scheduled for multiple radiotherapy sessions with sevoflurane anesthesia. To evaluate the development of sevoflurane tolerance, we analyzed changes in electroencephalographic spectral power at induction, across sessions. We fitted individual and group-level linear regression models to evaluate the correlation between the outcomes and sessions. In addition, a linear mixed-effect model was used to evaluate the association between radiotherapy sessions and outcomes.

RESULTS

Eighteen children were included and the median number of radiotherapy sessions per child was 28 (interquartile range: 10 to 33). There was no correlation between induction time and radiotherapy sessions. At the group level, the linear mixed-effect model showed, in a subgroup of patients, that alpha relative power and spectral edge frequency 95 were inversely correlated with the number of anesthesia sessions. Nonetheless, this subgroup did not differ from the other subjects in terms of age, sex, or the total number of radiotherapy sessions.

CONCLUSIONS

Our results suggest that children undergoing repeated anesthesia exposure for radiotherapy do not develop tolerance to sevoflurane. However, we found that a group of patients exhibited a reduction in the alpha relative power as a function of anesthetic exposure. These results may have implications that justify further studies.

Techniques and Complications of Anesthesia in Pediatric Radiotherapy: A Retrospective Cohort Study

BACKGROUND

Anesthesia during pediatric external beam radiation therapy poses a challenge, as radiotherapy rooms are not designed for the administration of anesthesia.

AIMS

We conducted a retrospective cohort study of children who underwent radiation therapy to describe the anesthetic approach and assess anesthetic-related complications.

MATERIALS AND METHODS

Data of all, who underwent radiation therapy under general anesthesia between November 2019 and January 2021, were recorded. Data were obtained from medical records, including demographic characteristics and information, regarding the anesthetic procedure and its associated complications. We describe our protocols for preoperative assessment, anesthetic procedures, and postanesthetic discharge evaluation.

RESULTS

Over the reporting period, 739 sessions of general anesthesia were performed. The mean number of radiation therapy rounds per patient was 23.5 sessions. Anesthetic induction was accomplished by sevoflurane inhalation in 639 sessions (86.4%) and intravenous propofol in the remaining 13.6%. General anesthesia was maintained with sevoflurane in all cases. Anesthesia-related complications occurred in 118 sessions (15.7%). The most frequent was nausea in 48 (6.4%) cases, followed by hypotension in 38 (5.1%). Airway-related complications occurred at a low frequency (2.3%), and all were resolved successfully with positive pressure ventilation. No patient hospitalizations were required because of any anesthetic complications.

CONCLUSIONS

Inhalation anesthesia is reliable and safe for pediatric patients undergoing radiation therapy.