Go to [Main HBOT page], [Table of Contents]

Low-Pressure Hyperbaric Oxygen Therapy (HBOT)
as an Investigational Treatment for Developmental Disabilities
including Rett Syndrome and Cerebral Palsy:
Theoretical Rationale, Early Results, Protocol, and Risk/Benefit Analysis

by

Earl M. Williams, Ph.D.

Abstract

Hyperbaric oxygen therapy (HBOT) involves the inhalation of 100% oxygen inside a chamber pressurized above sea-level atmospheric pressure (see Appendix A). HBOT substantially increases the amount of oxygen dissolved in all bodily fluids, including blood plasma, cerebrospinal fluid, and lymph. Increased oxygen in these fluids provides oxygen directly to underoxygenated (hypoxic) tissues, supplementing the usual transport system by hemoglobin molecules in the blood.

As a result of extensive civilian and military medical research, HBOT has become a standard, Medicare-reimbursable treatment in the United States for fourteen medical conditions and classes of injury. HBOT is the primary treatment for acute conditions including carbon monoxide poisoning, air/gas embolism, and decompression sickness. HBOT is an accepted adjunctive treatment for both acute and chronic conditions, including crush injuries, radiation osteonecrosis, and poor graft healing after severe burns.

Numerous medical studies show low-pressure HBOT to be an effective treatment for many additional indications in which local or global tissue hypoxia is present. Nevertheless, for non-medical reasons, current standard medical practice in the United States does not include the use of HBOT for these indications.

Among the most significant additional indications for which low-pressure HBOT is beneficial is brain injury caused by respiratory hypoxia or other brain insult, such as head trauma or stroke. These brain injuries produce regions of chronically reduced blood flow (hypoperfusion) in the brain, with consequent tissue hypoxia in these regions. SPECT scans (see Appendix B) have conclusively demonstrated that some neurons in these regions remain alive but are "idling" in a low metabolic state which prevents normal function. SPECT scans taken before and after a series of HBOT treatments have shown that HBOT can revive these idling neurons in many cases, producing long term improvement in both brain perfusion and clinical function.

SPECT scans have also shown regions of brain hypoperfusion in several developmental disorders including Rett Syndrome (RS) (see Appendix C) and cerebral palsy (CP). These disorders also share many symptomatic parallels with hypoxic brain injuries. The primary regions of brain hypoperfusion seen in RS are the frontal lobes and midbrain, regions which control functions that are typically abnormal in RS. Given the improvements in brain perfusion produced by HBOT in both hypoxic and non-hypoxic brain injuries, HBOT may also be beneficial in treating the brain hypoperfusion seen in RS, CP, and other developmental disorders. Early trials of HBOT for CP have produced promising results, and formal clinical trials are underway.

There is no evidence that low-pressure HBOT has any of the side effects associated with high-pressure HBOT (see Appendix D). Therefore, when an appropriate low-pressure protocol is used, the risks of HBOT are minor compared to the potential benefits.

For all these reasons, trials should be conducted to determine whether low-pressure HBOT can improve the brain hypoperfusion and functional abnormalities seen in RS.

Go to [Main HBOT page], [Table of Contents]

E-mail: earl@hbot.freeservers.com
Last revised: 000712 EMW