FAQs

Frequently Asked Questions About Hyperbaric Oxygen Treatment

• What is Hyperbaric Oxygen Treatment?
• How does breathing more oxygen help?
• How does HBOT lead to tissue recovery?
• What can HBOT help treat?
• How is HBOT administered?
• Is HBOT safe?
• Will the session be supervised?
• Are there any side-effects from HBOT?
• What are the relative contraindications?
• What are the absolute contraindications?
• Do high levels of oxygen present any complications?

What is Hyperbaric Oxygen Treatment

Hyperbaric Oxygen Treatment (HBOT), often called Hyperbaric Oxygenation Therapy, refers to the delivery of oxygen at greater than normal atmospheric pressure at sea level for a prescribed duration which is usually 60 to 90 minutes.

The air we normally breathe contains 21% oxygen, 78% nitrogen, with the remaining 1% being contributed by the noble gases and carbon dioxide. The concentration of these gases is determined by the atmospheric pressure which is determined by the weather and is reduced at altitude. Unfortunately the variations in this pressure are ignored in general medical practice. Atmospheric pressure is accorded the unit 1 to represent atmospheric pressure absolute (1 ata) and this unit is divided according to the percentages of the gases in air to give their ‘partial pressures’ that is the part of the total pressure each gas is responsible for – oxygen therefore being 0.21 ata (21% of 1) and nitrogen 0.78 ata (78% of 1).

A hyperbaric chamber is needed to allow the pressure around the body to be increased. The technology is very well established, in fact all commercial aircraft are hyperbaric chambers equipped with oxygen breathing systems.

How does breathing more oxygen help?

The air that we breathe usually provides enough oxygen for both normal body metabolism and repair to tissue damage after injury or illness. However increasing the pressure surrounding a patient in a hyperbaric chamber and using 100% oxygen can allow a very significant increase in the amount of oxygen dissolved in the bloodstream. This is in addition to the oxygen carried by haemoglobin. Normally the amount carried dissolved in plasma is about 0.3 ml per 100 ml of blood. At twice atmospheric pressure (2 ata) breathing 100% oxygen this increases to 3 ml oxygen in 100ml of blood. The increased concentration means that the gradient for the transport of free oxygen from blood into the tissues is increased 10 fold.

When tissues are damaged the capillaries within the tissues are also damaged which increases the distances for oxygen to diffuse. This can lead to a severe oxygen deficit in the tissues even when the amount of oxygen carried in the blood is normal. The object of using the increase in pressure and oxygen concentration is to raise tissue oxygen values towards normal to initiate normal cellular repair mechanisms.  In fact oxygen, like glucose and water is an essential substrate.

How does HBOT lead to tissue recovery

Oxygen is dissolved in the blood and transported, in combination with haemoglobin in the red blood cells throughout the body. This dissolved oxygen passes into the tissues. Breathing high levels of oxygen under hyperbaric conditions causes greater uptake of oxygen by the bodily fluids and so more can reach areas where the circulation is diminished or blocked and therefore improve recovery. The extra oxygen has additional benefits as it greatly enhances the ability of white blood cells to kill bacteria. It also reduces swelling and allows new blood vessels to grow more rapidly into the affected areas.

Severe tissue hypoxia (oxygen deprivation) has many adverse effects from abolishing normal cell activity as, for example, with loss of consciousness to disabling white blood cell activity in infection. Only the administration of oxygen can ‘treat’ hypoxia and the objective of the administration of oxygen is to establish tissue oxygen values compatible with the initiation of normal healing.

What can HBOT help treat?

HBOT may be beneficial in the treatment of the following conditions:

Alcohol and drug detoxification ^{1, 2}
Hyperbaric oxygen therapy has a documented role in alcohol and drug detoxification with claims that it reduces the time of withdrawal by up to half. It can also help reduce the symptoms and cravings experienced during nicotine withdrawal. ³

Asphyxiation
High dosages of oxygen can be life saving in asphyxiation, such as near-hanging and carbon monoxide poisoning. ⁴

Brain cell damage ⁵
HBOT can repair damaged brain cells, such as in alcohol and drug related cognitive impairment and there have been reports that it has had positive effects on Korsakoff’s syndrome.

Cancer
Administration of oxygen under hyperbaric conditions may enhance the delivery of oxygen to hypoxic tumour cells, thereby increasing their sensitivity to radiation and chemotherapy. ⁶

Cerebral Palsy ⁷ 

Cerebral stroke, brain trauma, and neurologic disease ^{8, 9} 

Chronic Multiple Sclerosis ¹⁰

Cognitive disorders ¹¹
Cognitive functioning in the aged

Decompression sickness and arterial gas embolism ¹²

Diabetes ^{13, 14}
HBOT has been used to treat diabetic food wounds and can prevent sufferers from losing limbs.

Leg Ulcers ¹⁵

Liver Disease
Alcoholic liver disease and cases of Hepatitis have been helped by HBOT. A phase I trial launched by the University of Edinburgh and Castle Craig Hospital in Scotland is currently examining alcoholic liver function following HBOT.

Lyme Disease ¹⁶

Stem Cells ¹⁷
HBOT increases the natural production of stem cells in the body by eightfold.

Radiation Injuries ^{18, 19}
There is a risk of serious complications developing after radiation treatment for cancer (late radiation tissue injury (LRTI). Radiation treatment kills good cells along with bad cells. With HBOT the destructive effect of radiation can be mitigated as HBOT improves oxygen supply to damaged tissue and stimulates healing.

Transplant surgery ²⁰
The viability of an amputated limb or organ can be extended up to 12 hours for re-implantation surgery.

Virus treatment
Breathing oxygen under pressure is virucidal i.e. it kills viruses.

Wound ²¹ and burn healing ^{22, 23}
HBOT helps to heal wounds and helps treat chronic ulceration.

Other
HBOT can aid sleep, thereby helping reduce insomnia, it also stimulates the appetite

How is HBOT administered?

HBOT is a simple, non-invasive and painless treatment which most patients find comfortable and relaxing. You will be treated in a secure and comfortable purpose built chamber with a trained operator present to operate the barochamber. In certain circumstances the attendant will accompany clients into the chamber. There has been no recorded case of a patient suffering either a heart attack or a stroke undergoing hyperbaric oxygen treatment, and oxygen under hyperbaric conditions can be used as a treatment of both conditions.

On entering the chamber clients can use a chair or, alternatively, they may sit on the floor.
It is recommended that you wear comfortable clothing and leave any jewellery or watches outside. No smoking materials, matches or lighters are allowed in the chamber.

The treatment session is conducted in three phases:

Compression:
Once the door is closed, there will be some noise as the pressure increases. It will get warmer and you will feel fullness in your ears similar to when descending in an aeroplane. You will have been taught how to avoid discomfort by clearing or ‘equalising’ your ears. As soon as the chamber pressure increases, you will need to start making your ears ‘pop’. There are several ways to do this and the chamber attendant will find the best way that suits you. Some people find that swallowing is sufficient. If you develop any discomfort inform the attendant and the rate of compression will be reduced. There may be a few unusual noises but this is normal as the chamber ‘descends’.

Treatment:
On reaching the desired pressure (usually 1.5 to 2.0 ata) the client places a mask over the head and breathes oxygen for the duration of the session. The treatment begins when the pressure reaches the prescribed level. You may then rest, sleep, read or watch television if your chamber is equipped with one. The mask can be removed occasionally and the chamber can be decompressed at any time if necessary.

Decompression:
After the prescribed amount of time has elapsed the attendant will let you know when the treatment is complete and the pressure will be lowered slowly, at a rate that is comfortable. A session usually lasts just over an hour and can be repeated daily. If a patient is receiving two treatments a day the second treatment follows the first after a three to four hour break outside the chamber. A patient receiving one treatment per day will spend about two hours at the treatment centre.

Is HBOT safe?

Whilst breathing oxygen, you cannot suffer decompression sickness ('the bends').

The chamber is a controlled environment that prevents traumatic injury. In 2003 the Department of Health accepted a Code of Construction and Working Practice for Barochambers for low pressure treatment based on aircraft pressure vessel standards which are accepted internationally. The term ‘barochamber’ is used to distinguish the chambers used for non-emergency elective clinical treatment from the high pressure chambers used in diving. The Healthcare Commission of England and Wales (but not Scotland) introduced regulations and annual inspections of facilities using barochambers designating them as Type 3 chambers.  Because of their perfect safety record, which applies to over 26 years of use, in 2008 the Commission deregulated Type 3 chambers.

Pulmonary Barotrauma is almost exclusively a problem in diving and results from a rapid ascent when the gas contained within the lungs is not been exhaled at an adequate rate. Chamber decompression is intrinsically safer because the rate of the reduction of pressure is far slower than when diving.  There has been no case of lung damage in patients using Type 3 barochambers.

Will the session be supervised?

All patients are supervised at the chamber by a trained attendant. The attendant will ensure that the patient has been given information beforehand regarding the procedure and the uses of Hyperbaric Oxygen Treatment. There would always be an operator present next to the chamber and patients are made aware of the system for communication. In the event of a patient becoming ill while in the chamber then assistance would be recruited using an intercom. The operator would begin the decompression and also call for medical assistance.Most hyperbaric oxygen treatment for non-acute conditions is delivered at between 1.5 and 2.0 ata which contrasts with the 71 ata achieved in experimental diving.

Are there any side-effects from HBOT?

There are few contra-indications for HBO treatment; in fact, the medical textbook Hyperbaric Medicine Practice states, "Of all the medical treatments carried out in hospitals, hyperbaric oxygen treatment is one of the most benign when it comes to side effects.”

Ear Pain
The discomfort is caused by a failure to equalise pressure in the middle ear via the Eustachian tube. The problem can usually be remedied by pinching the nose closing the mouth and pushing the tongue against the soft palate to force air through the Eustachian tube into the middle ear. It is usually avoided by slow compression and if this is unsuccessful the addition of periods of oxygen breathing.

Sinus Pain
Sinus pain due to blockage of the frontal sinuses is very rare and usually occurs in patients with upper respiratory infections or allergic rhinitis. As with ear pain it can usually be avoided by slow compression.

Claustrophobia
Claustrophobia is relatively common in the general population ~12% and you if you suffer from this problem you must tell chamber staff in advance so that due allowance can be made. Staff will always be on hand to offer reassurance and answer any questions you have.

Myopia
At low pressures of 2 ata it is most unlikely that visual changes will occur. Where an extended, intensive course of treatment is necessary, (as, for example, in wound healing), some patients may develop shortsightedness and need glasses.
This refractive change is temporary and reverses within a few weeks of stopping treatment.

Blood sugar reduction
A course of hyperbaric oxygen treatment results in a gradual reduction of the blood sugar level. It is recommended that those with insulin-dependent diabetes eat prior to each HBO treatment in order to maintain adequate blood sugar levels.

Note:
HBOT has been used in the NHS for more than 50 years and since 1982 it has also been used in the community. More than 1.6 million sessions have been carried out - 63,489 in 2004 - without a single serious problem!

Being inside a chamber is the safest place in the hospital because of the high levels of oxygen entering the body.

What are the relative contraindications?

If you suffer from the following a slow rate of compression may be needed:

Upper respiratory infections

These conditions can make it difficult for the patient to clear their ears and sinuses. Decongestants can be used, but it may be necessary to interrupt treatment for a few days until the infection clears if a trial of pressure fails.

High fevers
Patients with a significantly high temperature should first receive treatment for the underlying condition as fever predisposes to seizures

Seizure disorders
Hyperbaric oxygenation has been shown to be an effective treatment for epilepsy and patients with seizure disorders should be evaluated on a case by case basis. Patients with a known seizure disorder must be accompanied in the chamber by a competent person.

History of thoracic surgery or ear surgery
Such patients need to be evaluated prior to considering HBO treatment.

Pregnancy
A Russian study of women with severe congenital cardiac problems who received hyperbaric oxygen treatment for spontaneous abortion found that the treatment greatly reduced the rate of abortion. No foetal abnormalities occurred.

What are the absolute contraindications?

The one absolute contraindication to HBO treatment is untreated pneumothorax.

Patients should not undergo treatment if they are taking or have recently taken the following drugs:

• Doxorubicin (Adriamycin) - A chemotherapeutic drug.
• Disulfiram (Antabuse) - Used in the treatment of alcoholism.
• Cis-platinum - A cancer drug.
• Mafenide Acetate (Sulfamylon) - Suppresses bacterial infections in burn wounds

Do high levels of oxygen present any complications?

Pulmonary toxicity has not been reported using oxygen at 2 ata even with exposures as long as 30 hours and there have been no complications in type III hyperbaric chambers at this pressure.

Fire Safety
There has never been an accident due to fire in type 3 hyperbaric chambers and due to this safety record this is the type of chamber used at Castle Craig. The Department of Health in the UK believes that type 3 hyperbaric oxygen chambers do not need to continue to be regulated by the Healthcare Commission in order to ensure the provision of safe and effective services.  Even so, at Castle Craig all precautions are taken.

Bibliography

• Eric P. Kindwall MD and Harry T. Whelan MD, Editor, Hyperbaric Medicine Practice. Best Publishing Company. 1995.
• Wolfson Hyperbaric Medicine Unit Online. University of Dundee. Professor Philip B James MB ChB DIH PhD FFOM.
• Dr. M. McCann, Procedures for Hyperbaric Oxygen Treatment. Castle Craig Hospital. 2008.
  
  
  

References

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[2] Epifanova N, Romasenko M and and E, I. Hyperbaric oxygenation effect and the mechanisma of action in alcohol abuse and drug addiction. Presented at: 9th Congress of the Association of European Psychiatrists; Copenhagen, Denmark; 1998.

[3] Robert H. Granger, Oxygen as a Therapy for Reducing Nicotine Withdrawal Symptoms. Medical Hypotheses (2005) 65, 1161-1164.

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[5] Rockswold GL, Ford SE, Anderson DC et al. Results of a prospective randomised trial for treatment of severely brain-injured patients with hyperbaric oxygen. J Neurosurg, 1992, 76:929-34.

[6] US National Cancer Institute, NCI Drug Dictionary, http://www.cancer.gov/drugdictionary/?expand=H, Accessed 12th October 2009

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[8] Noori S. Al-Waili et al. Hyperbaric Oxygen in the Treatment of Patients with Cerebral Stroke, Brain Trauma, and Neurological Disease. Advances in Therapy vol.22 no.6. pp. 659-678. 2005.

[9] Neubauer.R.A. James.P. Cerebral oxygenation and the recoverable brain. Neurol Res 1998; 20 (Suppl 1): 533-536.

[10] Fischer BH, Marks M, Reich T. Hyperbaric-oxygen treatment of multiple sclerosis: a randomised, placebo-controlled, double-blind study. N Engl J Med, 1983, 308:181-6.

[11] Jacobs EA, Winter PM, Alvis HJK, Small SM. Hyperoxygenation effect on cognitive functioning in the aged. N Engl J Med, 1969, 281:753-7.

[12] US Navy Diving Manual. Diving Medicine and Recompression Chamber Operations. http://www.uhms.org/portals/0/DCS_AGE/recompression_Therapy_USN_Diving_Manual_Rev6.pdf Accessed 12th October 2009

[13] Faglia E et al. Adjunctive systemic hyperbaric oxygen therapy in treatment of severe prevalently ischemic diabetic foot ulcer. A randomized study. Diabetes Care 1996 Dec;19(12):1338-43.

[14] Doctor N et al. Hyperbaric oxygen therapy in diabetic foot. J Postgrad Med 1992 Jul-Sep;38(3):112-4, 111.

[15] Hammarlund C, Sundberg T. Hyperbaric oxygen reduced size of chronic leg ulcers: a randomised, double-blind study. Plast Reconstr Surg, 1994, 93:829-33.

[16] Dr. William P. Fife, Ph. D. Effects of Hyperbaric Oxygen Therapy on Lyme Disease, 29 Jan 1998

[17] Stephen R. Thom et al. Stem cell mobilization by hyperbaric oxygen. Am J Physiol Heart Circ Physiol 290: H1378-H1386, 2006. First published November 18, 2005; doi:10.1152/ajpheart.00888.2005

[18] Feldmeier JJ, Heimbach RD, Davolt DA, McDonough MJ, Stegmann BJ, Sheffield PJ. Hyperbaric oxygen in the treatment of delayed radiation injuries of the extremities. Undersea Hyperb Med 2000;27:15-9.

[19] Bennett MH, Feldmeier J, Hampson N, Smee R, Milross C. Hyperbaric oxygen therapy for late radiation tissue injury. Cochrane Database of Systematic Reviews 2008, Issue 3. Art. No.: CD005005. DOI: 10.1002/14651858.CD005005.pub2

[20] Zamboni WA, Roth AC, Russell RC et al. Morphologic analysis of the microcirculation during reperfusion of ischemic skeletal muscle and the effect of hyperbaric oxygen. Plast Reconstr Surg, 1993, 91:1110-23.

[21] Abbot NC, Beck JS, Carnochan FMT et al. Effect of hyperoxia at 1 and 2 ATA on hypoxia and hypercapnia in human skin during experimental inflammation. J Appl Physiol, 1994, 77:767-73.

[22] Niu AKC, Yang C, Lee HO, Chen SH, Chang LP. Burns treated with adjunctive hyperbaric oxygen therapy: A comparative study in humans. J Hyper Med 1987;2:75-86.

[23] Cianci P, Lueders H, Lee H, et al. Adjunctive hyperbaric oxygen reduces the need for surgery in 40-80% burns. J Hyperbar Med, 1988, 3:97-101.

[24] Private and voluntary healthcare: Care Standards Act 2000. Regulations and national minimum standards consultation document. March/June 2008. Product no. 280611. Gateway no 8565. Sourced online at: http://www.dh.gov.uk/en/Consultations/Liveconsultations/DH_083519