Hyperbaric oxygen therapy in experimental and clinical stroke

Abstract

Stroke, which is defined as a neurologic deficit caused by sudden impaired blood supply, has been considered as a common cause of death and disability for decades. The World Health Organization has declared that almost every 5 seconds a new stroke occurs, placing immense socioeconomic burdens. However, the effective and available treatment strategies are still limited. Additionally, the most effective therapy, such as thrombolysis and stenting for ischemic stroke, generally requires a narrow therapeutic time window after the event. A large majority of patients cannot be admitted to hospital and receive these effective treatments for reperfusion timely. Hyperbaric oxygen therapy (HBOT) has been frequently applied and investigated in stroke since 1960s. Numerous basic and clinical studies have shown the beneficial efficacy for neurological outcome after stroke, and meanwhile many underlying mechanisms associated with neuroprotection have been illustrated, such as cerebral oxygenation promotion and metabolic improvement, blood-brain barrier protection, anti-inflammation and cerebral edema, intracranial pressure modulation, decreased oxidative-stress and apoptosis, increased vascular and neural regeneration. However, HBOT in human stroke is still not sufficiently evidence-based, due to the insufficient randomized double-blind controlled clinical studies. To date, there are no uniform criteria for the dose and session duration of HBOT in different strokes. Furthermore, the additional effect of HBOT combined with drugs and other treatment strategies are being investigated recently. Therefore, more experimental and clinical research is imperative to identify the mechanisms more clearly and to explore the best protocol of HBOT in stroke treatment.

Combination therapy for ischemic stroke: Novel approaches to lengthen therapeutic window of tissue plasminogen activator

“…Additional well-designed clinical studies are necessary to further assess the safety and efficacy of NBO and HBO as treatments to be used to mitigate adverse complication associated with tPA. [ 29 49 59 60 61 ]…”

Adjunctive Therapy Approaches for Ischemic Stroke: Innovations to Expand Time Window of Treatment

“…It was suggested that NBO could increase tPA’s therapeutic window for ischemic stroke to at least 7 h. Rationally designed clinical studies with well-defined patient populations are required to validate whether NBO is a viable, safe, and efficacious adjunctive treatment for ischemic stroke [ 28 ]. Similarly, the documented therapeutic effects of HBO against experimental stroke [ 61 , 62 ] and in the clinic [ 63 , 64 ] warrant studies on its efficacy in combating tPA-induced complications.…”

Co-administration of tissue plasminogen activator and hyperbaric oxygen in ischemic stroke: a continued promise for neuroprotection

“…HBOT appears to be a potent way of oxygen delivery 131718. HBOT has been applied in the treatment of cerebral vascular diseases since the 1960s 1920. It is able to increase the oxygen partial pressure within the blood vessel and restore the oxygen supply after ischemic stroke 2122.…”