Delayed encephalopathy of carbon monoxide intoxication and treatment with hyperbaric oxygen: A case report [Karbonmonoksit i·ntoksikasyonuna bagli{dotless} gecikmiş ensefalopati ve hiperbarik oksijen uygulamasi{dotless}: Olgu sunumu]

Delayed encephalopathy (DE) is a neuropsychiatric syndrome that can generally arise within 20 days of acute carbon monoxide (CO) intoxication after apparent recovery and involves variable degrees of cognitive deficits, personality changes, movement disorders and focal neurologic deficits. We report a 35-year-old female patient with delayed encephalopathy due to CO intoxication, presenting with cognitive impairment and mild parkinsonism despite receiving hyberbaric oxygen therapy (HBO). Magnetic resonance imaging (MRI) showed abnormal signal intensity and decreased diffusivity at both caudate nuclei and globus pallidus. She continued to receive additional HBO therapy and recovered completely within six months. The positive effects of early HBO therapy in selected patients on reversing the acute effects of CO intoxication is apparent. Here, we also review the beneficial effect of HBO in preventing or limiting the late neurocognitive deficits associated with severe CO intoxication.