Hyperbaric oxygenation as an adjuvant therapy for traumatic brain injury: a review of literature

In recent years significant amount of data have been published in the filed of hyperbaric oxygenation (HBO) and traumatic brain injury (TBI). The main rational for the research in this field is that in TBI patients with the existence of dormant neural tissues that maintain cellular homeostasis but are unable to participate in neurotransmission, the addition of HBO provides a favourable environment by which neuronal reactivation can be achieved. As hyperbaric oxygen therapy is not all-or-nothing phenomena and the consequences of TBI can vary from mild to moderate and severe, it is important to evaluate each TBI patient before referring him/her to hyperbaric oxygen therapy (HBOT). Reports from the clinical trial that were investigating the effects of HBO on severe TBI show promising results. For example, significant reduction in mortality rates and improvement in favourable neurological outcomes were reported. However, conflicting results have been reported from trials that investigated the effects of HBO on mild and moderate TBI. The results from the experimental studies indicate that HBO can preserve mitochondrial function, reduce apoptosis and neuroinflammation and promote neuronal plasticity. Therefore, conducting of methodologically-based multicentric clinical trials is necessary to determine proper guidelines for inclusion of TBI patients in HBOT. As many reports have stated that even a few exposures to HBO can contribute to the recovery process, future research must be aimed at establishing most effective HBO protocol for TBI patients.