About | Canada Hyperbarics

The Fundamentals

What Is Hyperbaric Oxygen Therapy?

Hyperbaric oxygen therapy (HBOT) is a medical treatment in which a patient breathes 100% pure oxygen inside a pressurised chamber at pressures greater than normal atmospheric pressure — typically between 1.5 and 3.0 atmospheres absolute (ATA). Under these conditions, blood plasma becomes supersaturated with dissolved oxygen, delivering up to 10–15 times the normal oxygen concentration to tissues throughout the body.

This hyperoxygenation triggers a cascade of physiological responses including angiogenesis (new blood vessel growth), stem cell mobilization, enhanced white blood cell function, fibroblast proliferation, and reduction of inflammation. HBOT is recognised as a standard medical treatment by Health Canada, the UHMS, and healthcare systems worldwide.

01

Pressurisation

Chamber pressure increases to 1.5–3.0 ATA, compressing gases per Boyle's Law.

02

Oxygen Saturation

Per Henry's Law, plasma oxygen levels rise to 6+ mL/dL — a 20× increase over normal.

03

Tissue Repair

Hyperoxygenation activates angiogenesis, stem cell mobilization, and antimicrobial defences.

From 1662 to Today

The History of Hyperbaric Medicine

Hyperbaric medicine is one of the oldest forms of environmental therapy in Western medicine, with origins predating modern anaesthesia, antibiotics, and germ theory. Its evolution spans four centuries — from philosophical curiosity to evidence-based clinical practice.

1662

Henshaw's Domicilium

British physician Nathaniel Henshaw built the first known pressurised chamber — the domicilium — using organ bellows to raise and lower air pressure in a sealed room. He proposed that increased pressure could aid digestion and respiratory conditions. This is the earliest documented use of barotherapy.

1872

Fontaine's Mobile Operating Theatre

French surgeon J.A. Fontaine developed the first mobile hyperbaric operating theatre — a pressurised room on wheels. Within three months, 27 surgical operations were performed inside it. Surgeons found patients tolerated anaesthesia better and bled less under pressure.

1878

Paul Bert — The Father of Pressure Physiology

French physiologist Paul Bert published his landmark work La Pression barométrique, demonstrating that oxygen becomes toxic at high pressures (the "Bert effect" or CNS oxygen toxicity), and that partial pressure of oxygen — not total pressure — is the key variable. These findings remain foundational to all modern HBOT safety protocols.

1921–1928

Cunningham's Steel Ball

American physician Orville J. Cunningham observed that patients at sea level survived the 1918 influenza pandemic at higher rates than those at altitude. He built a six-storey steel sphere in Cleveland — the largest hyperbaric chamber ever constructed — offering compressed-air treatments to wealthy patients. The AMA investigated and found no scientific evidence; it was scrapped during the Great Depression. A cautionary tale about hyperbaric claims without evidence.

1937

U.S. Navy — Birth of Modern HBOT

The U.S. Navy began using pure oxygen (not just compressed air) at pressure to treat decompression sickness in divers — the critical distinction marking the birth of true hyperbaric oxygen therapy. During WWII, Navy research expanded to support combat diving operations, establishing the treatment tables still used today.

1956

Boerema — "Life Without Blood"

Dutch cardiac surgeon Ite Boerema performed open-heart surgery on a pig with no blood — the animal survived because its plasma was supersaturated with dissolved oxygen at 3 ATA. His 1960 paper "Life Without Blood" proved that hyperoxygenated plasma alone could sustain life, launching the modern clinical era.

1967

UHMS Founded

Six U.S. Navy diving and submarine medical officers founded the Undersea Medical Society (later renamed UHMS), establishing the professional body that now serves as the leading scientific society for hyperbaric medicine worldwide.

2015

CUHMA Established

The Canadian Undersea and Hyperbaric Medical Association launched as an independent national body, providing Canadian-specific accreditation, education, and standards of practice for hyperbaric medicine.

The Science

How HBOT Works in the Body

HBOT produces its therapeutic effects through several interconnected physiological mechanisms, each supported by peer-reviewed research. The treatment exploits fundamental gas laws to deliver supraphysiological oxygen concentrations to injured or hypoxic tissue.

Plasma Oxygen Levels by Condition

Condition	Plasma O₂	Increase
Breathing air at 1 ATA (sea level)	~0.3 mL/dL	Baseline
100% O₂ at 2.0 ATA	~4.0 mL/dL	13×
100% O₂ at 3.0 ATA	>6.0 mL/dL	20×

Source: StatPearls — Hyperbaric Physiological and Pharmacological Effects

Henry's Law — Oxygen Dissolution

The amount of gas dissolved in a liquid is directly proportional to the partial pressure of that gas above it. Under normal conditions, haemoglobin carries ~97% of the body's oxygen and plasma carries very little. At 3.0 ATA breathing 100% O₂, plasma oxygen rises to over 6 mL/dL — a 20-fold increase. This dissolved oxygen penetrates tissues where red blood cells cannot reach, including areas blocked by swelling or poor microcirculation. Source: StatPearls

Stem Cell Mobilization — An 8-fold Increase

HBOT activates nitric oxide synthase, triggering release of stem cell factor from bone marrow. A landmark 2006 study in the American Journal of Physiology demonstrated that HBOT produced an eight-fold increase in circulating stem/progenitor cells. These mobilised cells home to injured tissues, supporting repair and regeneration. PMID: 16299259

Angiogenesis — The Hyperoxia-Hypoxia Paradox

Repeated HBOT sessions create an oscillating cycle of hyperoxia (during treatment) and relative hypoxia (between treatments). This cycling induces HIF-1α, the master regulator of oxygen response, which triggers Vascular Endothelial Growth Factor (VEGF) production — resulting in new blood vessel formation in hypoxic wound beds. Source: Frontiers in Physiology

The Vasoconstriction Paradox

HBOT causes blood vessels to narrow — which seems counterproductive. But this vasoconstriction reduces swelling and oedema while the massive increase in plasma-dissolved oxygen more than compensates. Smaller oxygen molecules dissolved in plasma penetrate tissues even where red blood cells cannot pass. The net effect: more oxygen delivered to hypoxic tissue, not less. Source: StatPearls

Antimicrobial Effects

HBOT fights infection through three mechanisms: direct bactericidal action via reactive oxygen species toxic to anaerobic bacteria; restored immune function by enabling neutrophil oxidative burst killing in hypoxic tissue; and antibiotic synergy, enhancing certain antibiotics (especially aminoglycosides) against resistant organisms. Source: Biomedicine & Pharmacotherapy

Who Governs HBOT?

The Organizations Behind Hyperbaric Medicine

UHMS

Undersea & Hyperbaric Medical Society

The international scientific society that determines which conditions are approved indications for HBOT based on evidence review. Founded in 1967 by U.S. Navy medical officers, UHMS publishes the Hyperbaric Medicine Indications Manual (now in its 15th edition, 2024) and runs a facility accreditation programme.

Visit UHMS

CUHMA

Canadian Undersea & Hyperbaric Medical Association

Canada's national professional organisation for hyperbaric and diving medicine. Launched in October 2015, CUHMA is developing accreditation standards and pathways, and working toward broader provincial recognition, publishes the Standards of Practice Guidelines, and holds an annual scientific meeting accredited by the Royal College.

Visit CUHMA

ATMO

International ATMO, Inc.

The leading private hyperbaric education and consulting organisation in North America, training healthcare professionals for more than 40 years. ATMO is approved by the UHMS to deliver introductory hyperbaric courses including the 40-hour Hyperbaric Medicine Team Training (HMTT) programme.

Visit ATMO

Health Canada

Hyperbaric chambers are classified as Class III medical devices under Canadian Medical Devices Regulations, requiring a licence before import or sale. Health Canada's licensing framework covers 14 recognised conditions and explicitly warns against unsubstantiated claims.

Health Canada HBOT

Evidence-Based Conditions

UHMS Approved Indications for HBOT

The UHMS Hyperbaric Oxygen Therapy Committee maintains a list of indications supported by clinical evidence, updated in the 15th Edition (2024). Health Canada's device licensing framework covers 14 recognised conditions.

#	Indication	Health Canada
1	Air or Gas Embolism	✓
2	Carbon Monoxide Poisoning	✓
3	Clostridial Myositis and Myonecrosis (Gas Gangrene)	✓
4	Crush Injury, Compartment Syndrome & Acute Traumatic Ischemias	✓
5	Decompression Sickness	✓
6	Enhancement of Healing in Selected Problem Wounds	✓
7	Severe Anaemia (Exceptional Blood Loss)	✓
8	Intracranial Abscess	✓
9	Necrotizing Soft Tissue Infections	✓
10	Refractory Osteomyelitis	✓
11	Delayed Radiation Injury (Soft Tissue & Bony)	✓
12	Compromised Grafts and Flaps	✓
13	Acute Thermal Burn Injury	✓
14	Idiopathic Sudden Sensorineural Hearing Loss	✓
15	Central Retinal Artery Occlusion	—
16	CO Poisoning Complicated by Cyanide Poisoning	—
17	Avascular Necrosis (Added 2024)	—

Sources: UHMS Indications • Health Canada • ACEP 2024

Performance & Recovery

Athletes and Hyperbaric Oxygen Therapy

HBOT has become a cornerstone of recovery for elite athletes worldwide. While its use in sports is considered off-label (athletic recovery is not an approved medical indication), the physiological mechanisms — reduced inflammation, accelerated tissue repair, and enhanced oxygen delivery — have made it a standard tool in professional sports medicine.

The Terrell Owens Super Bowl Story

On December 19, 2004, Philadelphia Eagles receiver Terrell Owens suffered a fractured fibula. Doctors projected 16–18 weeks recovery — ruling him out of Super Bowl XXXIX, seven weeks away. Owens moved a hyperbaric chamber into his living room and committed to daily treatments. Just seven weeks after surgery, he played in the Super Bowl — catching 9 passes for 122 yards on 62 of 72 offensive snaps. It remains one of the most remarkable injury recoveries in NFL history.

Joe Namath — Brain Injury Recovery

NFL Hall of Famer Joe Namath suffered at least five concussions during his career. Brain imaging revealed virtually no blood flow in his left temporal lobe. After 120 HBOT treatments, the affected regions showed restored perfusion. Namath established the Joe Namath Neurological Research Centre at Jupiter Medical Center to research HBOT for traumatic brain injury. Note: HBOT for CTE/TBI is considered investigational and is not a recognised condition.

LeBron James

NBA

Installed a chamber at home; credits HBOT for sustained elite performance

Michael Phelps

Swimming

Used HBOT for recovery during Olympic training

Cristiano Ronaldo

Football

Owns a hyperbaric chamber; used for knee injury recovery

Novak Djokovic

Tennis

HBOT integrated into post-match recovery protocol

Neymar

Football

Used HBOT as part of injury rehabilitation

Georges St-Pierre

MMA (Canada)

Publicly reported using HBOT for recovery

Robert Thomas

NHL (Canada)

Used HBOT for hockey injury recovery

Philadelphia Flyers

NHL

First NHL team to formally integrate HBOT

Sources: MD Hyperbaric • NHL.com • Newmarket Health

The Canadian Landscape

Hyperbaric Oxygen Therapy in Canada

Canada has a growing network of hyperbaric facilities — both hospital-based programs delivering emergency and approved-indication treatments, and private clinics offering HBOT for a range of conditions. Regulatory oversight involves Health Canada (device licensing), provincial health authorities (facility accreditation), and professional bodies like CUHMA (clinical standards).

14

Health Canada Approved Indications

Class III

Medical Device Classification

25+

Facilities Across Canada

Regulatory Note

A CMAJ investigation found that no single federal or provincial agency consistently oversees day-to-day clinical operations of all HBOT clinics. CUHMA is actively working with the CSA, Royal College, and provincial ministries to develop enforceable national standards through its facility accreditation programme.

View All Canadian Facilities Explore Conditions

References

Sources & Citations

Gesell, L.B. (Ed.). Hyperbaric Oxygen Therapy Indications, 15th Edition. UHMS, 2024. uhms.org
Thom, S.R. et al. "Stem cell mobilization by hyperbaric oxygen." Am J Physiol Heart Circ Physiol, 2006. PMID: 16299259
Hopf, H.W. et al. "Hyperoxia and angiogenesis." Wound Repair Regen, 2005. Via Frontiers in Physiology
Gill, A.L. & Bell, C.N. "Hyperbaric oxygen: its uses, mechanisms of action and outcomes." QJM, 2004. StatPearls
Kindwall, E.P. & Whelan, H.T. Hyperbaric Medicine Practice, 3rd Edition. Best Publishing, 2008.
Camporesi, E.M. "Side effects of hyperbaric oxygen therapy." Undersea Hyperb Med, 2014.
Health Canada. "Hyperbaric Oxygen Therapy — It's Your Health." canada.ca
CUHMA. "Guidelines to the Practice of Clinical Hyperbaric Medicine." cuhma.ca
Stanec, Z. et al. "Unregulated hyperbaric oxygen therapy clinics assailed." CMAJ, 2010. PMC3001500
Bert, P. La Pression barométrique, 1878. Historical reference via LITFL
Jain, K.K. Textbook of Hyperbaric Medicine, 6th Edition. Springer, 2017.
Boerema, I. et al. "Life without blood." J Cardiovasc Surg, 1960. Via O2 Oasis

Understanding Hyperbaric Oxygen Therapy