Seizures during hyperbaric oxygen therapy: retrospective analysis of 62,614 treatment sessions.

INTRODUCTION: Hyperbaric oxygen (HBO₂) therapy is considered to be a generally safe therapy. However, data regarding seizure incidence during HBO₂ therapy as a clinical presentation of central nervous system- (CNS) related oxygen toxicity are conflicting (ranging from 1:10,000 to 1:600 seizures:hyperbaric sessions). The risk for seizures is of significant importance for the growing population of patients suffering from chronic neurological disorders such as traumatic brain injury and stroke who are treated with HBO₂. The aim of this study was to evaluate the incidence of seizures during HBO₂ therapy in a large cohort of patients and determine whether patients with known chronic neurological disorders are at increased risk.

METHODS: Retrospective analysis of 2,334 patients treated at the Sagol Center of Hyperbaric Medicine and Research, Assaf Harofeh Medical Center, Israel, between June 2010 and December 2014. Patients were grouped into one of three categories according to indication for HBO₂ therapy: Category A--non- neurological indications; Category B--neurological indications; and Category C--acute indications.

RESULTS: A total of 62,614 hyperbaric sessions, administered to 2,334 patients, were included in the analysis. The overall incidence of seizures during hyperbaric sessions was 0.011% (1:8,945), occurring in seven (0.3%) patients. Only one patient had a clear oxygen toxicity-induced seizure, with an overall incidence of 1:62,614.

CONCLUSIONS: Seizures induced by oxygen toxicity during HBO₂ therapy are extremely rare. Moreover, in relation to oxygen-induced seizures, HBO₂therapy can be considered safe for patients suffering with chronic neurological disorders except for uncontrolled epilepsy.