Hyperbaric oxygen therapy for traumatic brain injury: still an enigma

Hyperbaric oxygen for severe traumatic brain injury: a randomized trial

OBJECTIVE

The present study aimed to explore the effects of hyperbaric oxygen therapy on the prognosis and neurological function of patients with severe traumatic brain injury.

METHODS

A prospective study was carried out in 88 patients diagnosed with severe brain injury at our hospital and they were enrolled as research participants and randomly assigned to control and experimental groups (n = 44 per group) using a random number table method. Both groups underwent routine treatment. Patients in the experimental group were administered hyperbaric oxygen therapy approximately 1 week after admission when their vital signs had stabilized.

RESULTS

No significant intergroup differences were observed in the Glasgow Coma Scale (GCS) and U.S. National Institutes of Health Stroke Scale (NIHSS) scores before treatment. However, after oxygen treatment, compared with the control group, the experimental group showed higher GCS and lower NIHSS scores. The GCS score at admission, tracheotomy status, and first hyperbaric oxygen therapy duration were independent prognostic factors in patients with severe traumatic brain injury.

CONCLUSION

Hyperbaric oxygen therapy may promote recovery of neurological function and improve the cognitive function and prognosis of patients with severe traumatic brain injury.

Beneficial effects of hyperbaric oxygen on edema in rat hippocampus following traumatic brain injury

Hyperbaric oxygen (HBO) therapy helps alleviate secondary injury following brain trauma [traumatic brain injury (TBI)], although the mechanisms remain unclear. In this study, we assessed recovery of post-TBI spatial learning and memory in rats using the Morris water maze (MWM) and measured changes in apparent diffusion coefficient in the hippocampus by diffusion-weighted imaging (DWI) to evaluate possible therapeutic effects of HBO on TBI-associated brain edema. DWIs were obtained 8, 24, 48 h, 7 days, and 14 days post-TBI. Daily HBO therapy significantly improved post-TBI MWM performance and reduced edema in the ipsilateral hippocampus, suggesting that the therapeutic efficacy of HBO is mediated, at least in part, by a reduction in brain edema.

Clinical management of the minimally conscious state

The minimally conscious state (MCS) was defined as a disorder of consciousness (DoC) distinct from the vegetative state more than a decade ago. While this condition has become widely recognized, there are still no guidelines to steer the approach to assessment and treatment. The development of evidence-based practice guidelines for MCS has been hampered by ambiguity around the concept of consciousness, the lack of accurate methods of assessment, and the dearth of well-designed clinical trials. This chapter provides a critical review of existing assessment procedures, critically reviews available treatment options and identifies knowledge gaps. We close with practice-based recommendations for a rational approach to clinical management of this challenging population.

Autonomic dysfunction syndromes after acute brain injury

The central autonomic nervous system (CAN) is a multifaceted, richly connected neural network incorporating the hypothalamus, its descending tracts through the brainstem, the insular cortex and down into the spinal cord. All levels of the CAN are susceptible to injury following traumatic brain injury (TBI), whether from focal or diffuse injury. Focal injuries would be expected to produce localized damage to CAN control centers, whereas the effects of diffuse injuries are presumed to be more diverse and/or widely distributed. As the combination of focal and diffuse injury following TBI can vary widely from one individual to the next, the impact of focal injuries is best understood with reference to the focal ischemic stroke literature. Subarachnoid hemorrhage (SAH), a common complication following TBI, also has predictable effects on autonomic control that can be understood with reference to spontaneous SAH literature. Finally, paroxysmal sympathetic hyperactivity (PSH), a syndrome incorporating episodes of heightened sympathetic drive and motor overactivity following minor stimulation, is discussed as an example of what happens when central inhibitory control of spinal cord autonomics is impaired.

Quantitative evaluation of hyperbaric oxygen efficacy in experimental traumatic brain injury: an MRI study

To use DCE-magnetic resonance imaging (MRI) and diffusion-weighted imaging to evaluate the hyperbaric oxygen efficacy (HBO) in experimental traumatic brain injury (TBI). Forty-two rabbits were randomly divided into four groups: TBI, TBI + HBO, sham group, sham + HBO. The TBI + HBO and sham + HBO received a total of 10 HBO treatments within 7 days following TBI, and MRI was performed within a month after TBI. Functional assessments were performed pre-TBI, and at 1 and 30 days. In focal lesion area, K(trans) in TBI + HBO group was lower than TBI group at both acute and subacute phase (p < 0.05). ADC was higher in TBI + HBO group than TBI group at acute phase (p < 0.01), but lower at subacute phase (p < 0.05). In perifocal area, K(trans) were lower in TBI + HBO group than TBI group at acute phase (p < 0.01) after TBI. ADC was lower in the TBI + HBO group than in the TBI group at both acute and subacute phase (p < 0.01).The VCS was higher in TBI + HBO group than TBI group at 30 days (p < 0.05). HBO could improve the impaired BBB and cytotoxic edema after TBI and promote the recovery of neurofunction.

Tension pneumocephalus as a complication of hyperbaric oxygen therapy in a patient with chronic traumatic brain injury

Although hyperbaric oxygen therapy has not been accepted as a standard therapy for traumatic brain injuries, it has been used, along with rehabilitative exercises, for traumatic brain injuries, and the standard protocol has a low risk of complications. We report a case of chronic traumatic brain injury that progressed to tension pneumocephalus after hyperbaric oxygen therapy. The patient was a 25-yr-old man who presented with left occipital bone fracture and subarachnoid and subdural hemorrhage after being hit by a car. He underwent craniectomy to remove the hematoma and cerebrospinal fluid diversion with a ventriculoperitoneal shunt for the treatment of hydrocephalus. Fifteen months after the trauma, the patient received hyperbaric oxygen therapy to promote functional recovery. Tension pneumocephalus developed after the first session of hyperbaric oxygen therapy, and immediate burr hole drainage followed by ligation of the ventriculoperitoneal shunt was performed. The patient's consciousness recovered gradually, and he was discharged home. We suggest that patients with unrepaired skull base fracture and cerebrospinal fluid diversion should be carefully evaluated before receiving hyperbaric oxygen therapy.