Does hyperbaric oxygen therapy help with brain injuries? does-hyperbaric-oxygen-therapy-help-with-brain-injuries

Research shows that more than 3 billion people worldwide suffer from neurological diseases. "Neurological diseases bring great suffering to affected individuals and families, and deprive communities and economies of human capital," said Dr. Tedros Adhanom Ghebreyesus, Director-General of the World Health Organization.

As a non-invasive treatment, hyperbaric oxygen chamber therapy has been widely studied to improve a variety of neurological diseases, such as stroke, brain trauma, Alzheimer's disease, and migraine. By inhaling nearly 100% pure oxygen in a high-pressure environment, this therapy can promote brain oxygen supply, reduce inflammation, and accelerate neural repair, providing patients with a new rehabilitation option to help them rebuild their quality of life while reducing social and economic burdens.

[ Reference: 

Global, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

Steinmetz, Jaimie D et al.

The Lancet Neurology, Volume 23, Issue 4, 344 - 381]

What is HBOT？

Hyperbaric oxygen chamber therapy is a medical technology that allows patients to inhale pure oxygen or high-concentration oxygen in a sealed chamber at a pressure higher than normal (usually 1.3-3 atmospheres) to increase the dissolved oxygen content in the blood, thereby improving tissue hypoxia, promoting repair and alleviating diseases. The core principle is that the physical dissolution of oxygen in a high-pressure environment is greatly increased, allowing oxygen to more effectively penetrate ischemic or damaged tissues, accelerating cell metabolism and recovery.

Ordinary oxygen inhalation vs Hyperbaric oxygen chamber therapy

Top 10 neurological diseases that cause loss of health

• Stroke

• Neonatal encephalopathy (brain damage)

• Migraine

• Dementia

• Diabetic neuropathy (nerve damage)

• Meningitis

• Epilepsy

• Neurological complications of premature infants

• Autism spectrum disorder

• Cancer of the nervous system

[ Reference: 

World Health Organization. Over 1 in 3 People Affected by Neurological Conditions, the Leading Cause of Illness and Disability Worldwide. 14 Mar. 2024, Geneva, Switzerland,]

5 Dilemma of Traditional Therapy for Brain Injury

• Insufficient control of brain edema

Traditional treatments are difficult to effectively relieve arterial compression (ischemia) and venous return obstruction (worsened edema) caused by brain edema, forming a vicious cycle. Brain edema will also widen the distance between capillaries, causing distal cells to die due to hypoxia. a

• Limited oxygen diffusion distance

The oxygen diffusion radius of gray matter capillaries under normal pressure is only 30 microns. Traditional oxygen inhalation cannot cover the distal cells in the edema or ischemic area, resulting in many "dying cells" that are difficult to save.

• Lack of neural repair mechanism

Traditional methods (such as drugs and surgery) cannot activate the neural regeneration signal pathway, have no repair effect on necrotic neurons, and have limited improvement in sequelae (such as hemiplegia and aphasia).

• Low metabolic recovery efficiency

Brain cells rely on continuous oxygen and glucose supply for aerobic metabolism. Traditional treatment makes it difficult to quickly rebuild the metabolic cycle of the damaged area, resulting in insufficient ATP production and expanded cell death.

• Difficulty in awakening and functional activation

Because the ascending activation system of the brainstem is impaired in comatose patients, traditional rehabilitation methods (such as physical stimulation) have a slow awakening effect and cannot directly improve the blood oxygen supply to the brainstem.

5 Advantages of Hyperbaric Chamber Therapy for Brain Injury

• Efficiently relieve brain edema and hypoxia.

Hyperbaric oxygen expands the capillary oxygen diffusion radius to 100 microns, penetrates the edema area, directly supplies oxygen to the "inter-ecological" cells, and reduces cell death. At the same time, it constricts blood vessels, reduces exudation, and breaks the vicious cycle of "edema-hypoxia" (Professor Liu Qingle emphasized that this is the core mechanism).

• Promote metabolism and neural repair.r

By quickly restoring aerobic metabolism, increasing ATP production, and repairing cell membrane channel function (such as sodium-potassium pump). At the same timeactivateste the Nrf2 signaling pathway to inhibit cell apoptosis, promote the expression of neurotrophic factors, and accelerate neural regeneration (reference content mentions that the expression of apoptotic genes is reduced).

• Enhance the targeted efficacy of drugs.

Hyperbaric oxygen increases the permeability of the blood-brain barrier and increases the concentration of antibiotics and chemotherapy drugs in the infected or tumor site by 3-5 times. Synergistically enhance the anti-inflammatory and anti-tumor effects (mentioned in Professor Liu Qingle's case).

• Accelerate the awakening of comatose patients.

By increasing the blood oxygen supply to the brainstem reticular structure, the ascending activation system is activated and the coma time is shortened. Clinical data show that early hyperbaric oxygen therapy can increase the awakening rate of comatose patients by 30%-50%.

• Multi-pathway inhibition of secondary injury

Inhibit the NF-κB inflammatory pathway and reduce the release of pro-inflammatory factors such as IL-6 and TNF-α (the reference content mentions that the inflammatory signaling pathway is inhibited). At the same time, it enhances the activity of superoxide dismutase, scavenges free radicals, and protects the integrity of cell membranes.

3 risks must be guarded against in hyperbaric oxygen chamber therapy

Risk of barotrauma (incidence rate is about 8%)

• Main manifestations

Middle ear barotrauma (ear pain, congestion/perforation of tympanic membrane), and sinus barotrauma (facial pain, nose bleeding), often occur during the pressurization stage.

• Risk groups

Patients with colds/rhinitis, patients with poor Eustachian tube function (such as infants and young children), and comatose patients (cabin companions are required to assist in adjustment).

• Preventive measures

Actively swallow, chew, pinch the nose, and blow air during pressurization.

The accompanying personnel will assist the comatose patients to raise their heads and open their mouths or feed a small amount of water.

Control the pressurization speed and increase the pressure slowly.

Risk of oxygen toxicity

• Types and thresholds

Pulmonary oxygen toxicity: common in long-term inhalation of pure oxygen (such as >2ATA continuous oxygen inhalation for 2 hours).

Cerebral oxygen toxicity: epilepsy may occur suddenly when the pressure is >3ATA (rare in medical treatment).

Hemolytic oxygen toxicity: ultra-high pressure (>4ATA) may damage the red blood cell membrane.

• High-risk scenarios

Overpressure treatment (such as medical misuse in diving), uncontrolled oxygen therapy parameters for premature infants, and insufficient oxygen monitoring for comatose patients.

• Countermeasures

Medical cabins strictly limit the time of single oxygen inhalation.

Use intermittent oxygen inhalation (oxygen inhalation for 20 minutes → air for 5 minutes cycle).

Immediately stop oxygen inhalation and decompress when convulsions/dry coughs/nausea occur.

Absolute contraindications: untreated pneumothorax and severe bullae

• Fatal risk

Aggravated alveolar rupture (enlarged pneumothorax) and rupture of bullae lead to tension pneumothorax (mortality rate 30%-50%) under a high-pressure environment.

• Other contraindications

Relative contraindications: severe emphysema (prone to pneumothorax), uncontrolled epilepsy (oxygen poisoning induces convulsions).

Contraindications for special populations: early pregnancy (affecting fetal development), active internal bleeding (clearly listed in the reference content).

• Screening points

Chest X-ray/CT examination must be performed before treatment to rule out occult bullae or old pneumothorax.

[ Reference: 

Schimmel, S., El Sayed, B., Lockard, G., Gordon, J., Young, I., D'Egidio, F., Lee, J. Y., Rodriguez, T., & Borlongan, C. V. (2023). Identifying the Target Traumatic Brain Injury Population for Hyperbaric Oxygen Therapy. International journal of molecular sciences, 24(19), 14612. https://doi.org/10.3390/ijms241914612]