Effect of free radical scavenger, edaravone, for patients with carbon monoxide poisoning

• The aim was to clarify the effects of a free radical scavenger, edaravone, in CO-poisoned patients.
• We compared 2 groups comprising patients treated with and without edaravone.
• Edaravone represents a tolerable and feasible treatment for CO-poisoned patients.
• Edaravone did not affect to frequency and improvement of chronic symptoms after CO poisoning.

ObjectiveChronic neurological symptoms after carbon monoxide (CO) poisoning are caused by various biological processes in the damaged brain, with free radicals playing roles as mediators in establishing pathological processes leading to chronic neurological symptoms under CO poisoning. This study aimed to clarify the effects of a free radical scavenger, edaravone, in patients with CO poisoning.MethodsWe retrospectively compared two groups comprising patients treated with hyperbaric oxygenation alone (Group A, n = 25) or edaravone in addition to hyperbaric oxygenation (Group B, n = 25). Edaravone was administrated intravenously at 30 mg every 12 h for 7 days. Patient characteristics, general conditions on admission, and frequency of chronic neurological symptoms were compared between groups. Among patients showing chronic neurological symptoms, cognitive function and daily activity were also compared between groups.ResultsNo significant differences in characteristics or general conditions on admission were identified between groups. In Group B, no patients presented with marked complications caused by edaravone. Although chronic persisting symptoms were less frequent in Group B (n = 1, 0.04%) than in Group A (n = 5, 20%), this difference was not significant. In the 11 patients showing chronic symptoms, scores for cognitive function and daily activity in the chronic phase were better in Group B than in Group A, but no significant differences were apparent.ConclusionsThe present results suggest that edaravone represents a tolerable and feasible treatment for CO-poisoned patients. Further studies are needed to clarify whether edaravone can favorably influence chronic neurological symptoms caused by CO poisoning.