Purpose: Cognitive impairment may occur in 42-50% of cardiac arrest survivors. Hyperbaric oxygen therapy (HBO2) has recently been shown to have neurotherapeutic effects in patients suffering from chronic cognitive impairments (CCI) consequent to stroke and mild traumatic brain injury.The objective of this study was to assess the neurotherapeutic effect of HBO2 in patients suffering from CCI due to cardiac arrest.
Methods: Retrospective analysis of patients with CCI caused by cardiac arrest, treated with 60 daily sessions of HBO2. Evaluation included objective computerized cognitive tests (NeuroTrax), Activity of Daily Living (ADL) and Quality of life questionnaires. The results of these tests were compared with changes in brain activity as assessed by single photon emission computed tomography (SPECT) brain imaging.
Results: The study included 11 cases of CCI patients. Patients were treated with HBO2, 0.5-7.5 years (mean 2.6 ± 0.6 years) after the cardiac arrest. HBO2 was found to induce modest, but statistically significant improvement in memory, attention and executive function (mean scores) of 12% , 20% and 24% respectively. The clinical improvements were found to be well correlated with increased brain activity in relevant brain areas as assessed by computerized analysis of the SPECT imaging.
Conclusions: Although further research is needed, the results demonstrate the beneficial effects of HBO2 on CCI in patients after cardiac arrest, even months to years after the acute event.
Keywords: Anoxic brain damage; SPECT; cognitive symptoms; hyperbaric oxygen therapy; rehabilitation.