Neurology India
menu-bar5 Open access journal indexed with Index Medicus
  Users online: 3800  
 Home | Login 
About Editorial board Articlesmenu-bullet NSI Publicationsmenu-bullet Search Instructions Online Submission Subscribe Videos Etcetera Contact
  Navigate Here 
 Resource Links
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
    Article in PDF (433 KB)
    Citation Manager
    Access Statistics
    Reader Comments
    Email Alert *
    Add to My List *
* Registration required (free)  

  In this Article

 Article Access Statistics
    PDF Downloaded62    
    Comments [Add]    

Recommend this journal


Table of Contents    
Year : 2019  |  Volume : 67  |  Issue : 3  |  Page : 655-656

Hyperbaric oxygen therapy in neurological diseases

1 Department of Neurology, Command Hospital (SC), Pune, Maharashtra, India
2 Department of Neurology, P D Hinduja National Hospital and Medical Research Center, Mumbai, Maharashtra, India

Date of Web Publication23-Jul-2019

Correspondence Address:
Dr. Charulata S Sankhla
Department of Neurology, P D Hinduja National Hospital, Mahim, Mumbai - 400 016, Maharashtra
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0028-3886.263204

Rights and Permissions

How to cite this article:
H Ahmad FM, Sankhla CS. Hyperbaric oxygen therapy in neurological diseases. Neurol India 2019;67:655-6

How to cite this URL:
H Ahmad FM, Sankhla CS. Hyperbaric oxygen therapy in neurological diseases. Neurol India [serial online] 2019 [cited 2020 Jul 4];67:655-6. Available from:

Hyperbaric oxygen therapy (HBOT) is defined by the Undersea and Hyperbaric Medical Society (UHMS), as administration of oxygen intermittently or continuously inside a chamber at supra-atmospheric pressures (>1.4 atm).[1],[2],[3],[4] This modality, first invented in 1662 by Henshaw as the “domicillium”, has been used for about a century, initially in many disorders. This was later approved in decompression sickness and later extensively in altitude related disorders.[5] The therapy is usually safe and associated with only mild side effects, primarily some confusional and pulmonary effects. The major adverse effects are related to barotrauma affecting the middle ear.

The delivery of oxygen at higher concentrations has been utilised in conditions where there has been an element of tissue hypoxia, or in infective conditions, to attenuate anaerobic conditions and promote tissue healing. As such, HBOT has been investigated and evaluated for many infective, metabolic and other diseases. However, the results have been conflicting. The UHMS has recommended a list of conditions wherein HBOT should be an adjunct to therapy.[3]

In India, the majority of these chambers are in use with the armed forces, being utilised by the Navy for divers with decompressive sickness, and in the Army among soldiers with altitude sickness in high altitude areas. Significantly, the indications mentioned by the Undersea and Hyperbaric Medical Society do not list altitude sickness as an indication, and do not define normobaric oxygen therapy in high altitude as a component of hyperbaric therapy ![3]

Among neurological conditions, HBOT has been evaluated among patients of stroke, cerebral palsy, injuries of the brain and spinal cord, multiple sclerosis, migraine, increased intracranial pressure, hydrocephalus, etc.[5] The proposed mechanisms of benefit include inhibition of multiple inflammatory mediators and cascades, promotion of angiogenesis, reduction of cerebral oedema, increased delivery of oxygen to neuronal tissues and reduction of cellular ischemia, among others.[1],[2],[4],[5] The list of conditions where attempts have been futile is, however, more exhaustive and often contradictory.[1] Nevertheless, there have been claims made especially in popular media about its benefits without adequate or supportive proof for a number of conditions and corresponding “off label” uses bordering on malpractice. There has been concerning and encouraged disdain towards HBO in the medical scientific community. Thus, controversy exists regarding the efficacy of HBOT in mainstream neurology. The primary effects of the HBOT include improving oxygen delivery and increasing the oxygen tension to hypoxic induced injury, an enhancement of the antimicrobial activity, and the attenuation of the hypoxia inducible factor mediated effects. The secondary benefits involve the indirect effects of HBOT in improving the ability of the injured tissues to heal, its anti-inflammatory action, and its ability to produce vasoconstriction and angiogenesis. The HBOT pressures and duration, however, differ between treatment centres, and lack standard as well as uniform protocols. Usually, lower oxygen tensions are preferred to avoid the side effects of barotrauma.

The mechanism of action of the HBOT treatment is due to its ability to improve the tissue oxygen deficiency. It is postulated to stimulate healing and angiogenesis. It helps to improve the ability of the immune system to fight infection and reduce inflammation. The secondary injury process that follows the acute insult may be reduced by the HBOT.

HBOT has many current indications for treatment due to its ability to control inflammation and repair the immune system.

The study by Sankaran et al., in this issue of the journal has focussed on HBOT in hypoxic ischemic encephalopathy (HIE).[6] In a nonrandomised study design, the authors have administered HBOT as per two protocols to 25 patients of HIE. The ictus had to be one to 12 months prior to the recruitment of subjects. The patients were assessed based on the Degree of Consciousness scale (DOC), Karnofsky's performance score and the Coma Recovery Scale – Revised (CRS-R). Two differing protocols were used for administration of HBOT after consent from the patients. Twenty sessions of one hour duration of HBOT at 2 atm were administered to 23 patients and two patients received three sets of twenty sessions, for 60 such sessions. Data were analysed for three groups based on the interval since the ictus as 1–3 months, 4–8 months and 9–12 months.

The data analysis revealed that though there was no difference in the Karnofskys performance score, the study group fared better in the scores on the CRS-R, especially in the oro-motor, visual and auditory domains. These effects were more pronounced in the group closer in timing to the ictus. The authors report that the controls reached a minimally conscious state more often.

However, the study suffers from the issues related to sample size, non-randomisation, a baseline favouring the cases and soft secondary outcomes.

Nevertheless, the study has focussed on HBOT once again, notwithstanding the controversial past of the modality and the potential for misuse. The results are definitely food for thought and lay the ground for larger, randomised controlled trials of HBOT in HIE.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

Gill AL, Bell CNA. Hyperbaric oxygen: Its uses, mechanisms of action and outcomes. QJM 2004;97:385-95.  Back to cited text no. 1
Tibbles PM, Edelsberg JS. Hyperbaric-oxygen therapy. N Engl J Med 1996;334:1642-8.  Back to cited text no. 2
Gesell LB. Hyperbaric Oxygen Therapy Indications, 12th ed. Durham, NC: Undersea and Hyperbaric Medical Society; 2008.  Back to cited text no. 3
Leach RM, Rees PJ, Wilmshurst P. Hyperbaric oxygen therapy. BMJ 1998;317:1140-3.  Back to cited text no. 4
Al-Waili, N, Butler GJ, Beale J, Abdullah MS, Hamilton RW, Lee BY, et al. Hyperbaric oxygen in the treatment of patients with cerebral stroke, brain trauma, and neurologic disease. Adv Ther 2005;22:659-78.  Back to cited text no. 5
Sankaran R, Radhakrishnan K, Sundaram KR. Hyperbaric oygen therapy in patients with hypoxic ischemic encephalopathy. Neurol India 2019;67:728-31.  Back to cited text no. 6
  [Full text]  


Print this article  Email this article
Online since 20th March '04
Published by Wolters Kluwer - Medknow