The Remarkable History of Hyperbaric Medicine ⚕️ Past to Present

The Ancient Roots of Hyperbaric Medicine

The history of hyperbaric medicine is deeply connected to the evolution of diving and the use of compressed gases in therapeutic contexts, with roots stretching back to ancient times. Though little is known about the earliest diving practices, records indicate that as far back as 4500 B.C., free-diving for mother-of-pearl was a recognized profession. By 320 B.C., Alexander the Great was reportedly lowered into the Bosphorus Straits in a glass barrel, marking one of the earliest documented uses of a pressurized environment. During the 1500s, Leonardo Da Vinci even sketched diving devices, though none were realized. Nevertheless, these early innovations laid the groundwork for future developments in hyperbaric therapy.

The First Experiments in the History of Hyperbaric Medicine

In 1620 Dutch inventor Cornelius Drebbel invented the first true diving bell. It had an open bottom and relied on the pressure of water to keep air trapped within the bell. The bell would be lowered into the water by crane and had ballast to keep the bell properly oriented. Air was pumped into the bell by a hose to keep fresh air within while excess gases would leak out from under the lip of the bell. As the bell sank deeper more air was pumped inside to keep the occupants comfortable. The bell was never meant to move under the control of the divers but served as an underwater base for free divers.

The first documented use of hyperbaric therapy actually came before the discovery of oxygen. In 1662, British clergyman named Joseph Henshaw, used a system of organ bellows to change the atmospheric pressure in a sealed chamber called a domicilium. This domicilium could create both hyperbaric and hypobaric environments. Despite lacking any scientific basis for his theories, Henshaw believed that acute conditions would benefit from increased air pressure, while chronic conditions would respond better to decreased air pressure. According to Henshaw, “In times of good health this domicilium is proposed as a good expedient to help digestion, to promote insensible respiration, to facilitate breathing and expectoration, and consequently, of excellent use for the prevention of most afflictions of the lungs.” Henshaw was only providing increased and decreased air pressure without increasing oxygen concentration. Oxygen was not discovered until 1773 by Swedish pharmacist Carl Wilhelm Scheele (although Joseph Priestley published his findings first), and the term “oxygen” was not coined until 1777 by French chemist Antoine Lavoisier.

The 19th Century Hyperbaric Revival ⚕️ A Turning Point in the History of Hyperbaric Medicine

Nearly two centuries later, in the 1830s, France saw a resurgence that shaped the history of hyperbaric medicine, led by innovative physicians like Junod and Fabare. In 1834, Junod, with assistance from steam engine inventor James Watt, designed and built a copper sphere hyperbaric chamber capable of reaching pressures of 2 to 4 atmospheres (ATA). Known as “Le Bain d’air comprimé” (the compressed air bath), this chamber was primarily used to treat pulmonary diseases, and Junod reported improvements in circulation to internal organs, enhanced cerebral blood flow, and an overall sense of well-being in patients. By 1837, interest had expanded, and Pravaz constructed a larger hyperbaric chamber in Lyon that could seat 12 patients. This chamber was used for various conditions beyond respiratory issues, including tuberculosis, cholera, and conjunctivitis, marking a significant step in the early applications of hyperbaric therapy and contributing to the foundation of the history of hyperbaric medicine.

In 1859, the history of hyperbaric medicine recorded its first documented death from Caisson Disease, now known as Decompression Illness (DCI) or “the bends,” during construction of England’s Royal Albert Bridge, where workers became ill after working under high-pressure conditions deep underground. Later, in 1873, Andrew Smith coined the term “caisson disease” to describe 110 cases of decompression sickness during the Brooklyn Bridge construction, which employed 600 compressed air workers but lacked on-site recompression treatment. Similarly, during the 1882 Hudson tunnel project in New York, one in four workers succumbed to the bends until a recompression chamber was introduced. Afterward, only three workers died of bends over the following 18 months.

Fontaine’s Breakthrough and Tragic End

In 1877, French surgeon Fontaine developed the first mobile hyperbaric operating room, using Henry’s Law, which states that the solubility of gas in a liquid increases with pressure. This innovative chamber was designed to aid surgeries, reduce hernias, and treat conditions like asthma, chronic bronchitis, emphysema, and anemia. Fontaine’s chamber, equipped with bellows, windows for natural light, and a small medical lock for transferring items, seated up to 10 people. Over three months, twenty-seven operations were successfully performed, prompting plans for a larger hyperbaric surgical amphitheater to seat 300, though it was never realized. Tragically, Fontaine died in an accident at the Pneumatic Institute, becoming the first physician martyr in hyperbaric medicine history.

Expansion into the 20th Century ⚕️ Foundations of Hyperbaric and Diving Medicine

In 1908, Scottish physiologist John S. Haldane began pioneering experiments at London’s Lister Institute of Preventive Medicine, working with Royal Navy Lieutenant Guybon Damant, an experienced diver, and physiologist Edwin Arthur Boycott. To start, they assembled a herd of 85 goats, placing groups in compression chambers for controlled durations. After decompression by stages, the animals were released, and as expected, observations confirmed that gradual decompression prevented symptoms of the bends. Furthermore, through these studies, Haldane introduced the concept of “half times”—the period required for tissue to become half-saturated with gas—and thus developed decompression protocols, particularly effective at shallower depths. As a result, these findings led to the creation of Admiralty decompression tables for the Royal Navy, which became essential for preventing decompression sickness. Haldane, known for his bold self-experimentation, significantly advanced our understanding of gases and human physiology. In 1910, influenced by his work, the German Navy equipped the SMS Vulkan with a sanitary lock to provide immediate hyperbaric treatment to divers, thereby reinforcing the critical connection between diving and hyperbaric medicine.

Advancements in Hyperbaric Simulation

The 1910s marked significant advancements in the history of hyperbaric medicine research. For instance, in 1912, the U.S. Navy developed diving simulators, including a testing tank with dimensions of 2.14 meters in diameter, 3.05 meters in height, and featuring a central access shaft. Similarly, in 1913, Germany introduced its own simulators, specifically designed to examine human responses to breathing pure oxygen in hyperbaric environments. To illustrate, the Drägerwerk Lubeck testing tank, with a diameter of 2 meters and a height of 3 meters, could reach pressures up to 20 bar, making it a key tool in hyperbaric studies. By 1917, portable hyperbaric chambers had also emerged, making it easier to treat divers and expand the applications of hyperbaric therapy.

Military and Diving Applications

Heinrich Dräger was the first to explore the use of pressurized oxygen in decompression sickness. His protocols were put into practice by Behnke and Shaw in the late 1930s. In 1939, the US Navy began treating divers suffering decompression sickness with hyperbaric oxygen therapy. This was different than all of the previous uses of hyperbaric therapy which only used compressed air.

After World War II, the U.S. military’s research contributed greatly to the history of hyperbaric medicine by deepening the understanding of survivable pressure levels. As a result of these advancements, the late 1950s and early 1960s saw a marked increase in the use and acceptance of hyperbaric oxygen therapy (HBOT), setting the stage for modern applications in both medical and therapeutic fields.

Modern Hyperbaric Oxygen Therapy ⚕️ Advancements Rooted in the History of Hyperbaric Medicine

In the 1950s, Ite Boerema of the Netherlands conceived the idea of “flooding” the body’s tissues with extra oxygen. Cardiac surgeon Boerema worked with the Royal Dutch Navy in a number of animal experiments with surgery inside a hyperbaric oxygen chamber. His results were so successful that a large operating hyperbaric chamber room was built at the University of Amsterdam where he would perform a number of complicated heart and lung operations. Boerema and his team were the first ever to treat Clostridial Myonecrosis (Gas Gangrene) with HBOT using an experimental pig. Boerema published, “Life without blood,” a report of fatally anemic pigs treated successfully with HBOT. These pigs were able to thrive within the hyperbaric chamber even in the complete absence of circulating red blood cells.

Hyperbaric Organizations and Clinics

The Undersea Medical Society, an organization made up largely of Navy and ex-Navy physicians, was founded in 1967 in the USA. This non-profit organization is now known as the Undersea and Hyperbaric Medical Society (UHMS). And with concerns of the lack of scientific progress and regulation, the UHMS formed a Committee on Hyperbaric Oxygen Therapy in the late 1970s and systematically reviewed all the available scientific evidence for HBOT. They came up with a list of conditions for which HBOT was likely beneficial. This list was accepted by insurance providers, including Medicare.

In 1972, Dr. Richard A. Neubauer opened the Ocean Hyperbaric Neurologic Center in Lauderdale by the Sea. Throughout his life, despite being viewed with suspicion by skeptics, Dr. Neubauer continued to treat and report the effectiveness of hyperbaric oxygen therapy in the management of various central nervous system disorders. Neubauer is considered the grandfather of HBOT in Neurology.

Dr. Paul Harch began an in-depth study of brain decompression illness (DCI) and evaluated divers with this disorder. Two diving cases confirmed what became obvious to Harch; it was not residual gas being treated rather ischemic brain injury.

Hyperbaric Oxygen Therapy Today ⚕️ Insights from the History of Hyperbaric Medicine

The history of hyperbaric medicine has laid the foundation for today’s Hyperbaric Oxygen Therapy (HBOT), which is now widely available in thousands of clinics worldwide. Clinics offer both traditional hard-shell chambers and portable soft-shell models, making HBOT more accessible than ever. As awareness of HBOT’s benefits grows, it is increasingly being used for conditions such as autism, traumatic brain injury (TBI), and stroke. Nevertheless, despite ongoing research and numerous success stories, it remains puzzling why the Undersea and Hyperbaric Medical Society (UHMS) and the FDA have not expanded their list of approved conditions for HBOT in recent years. As a result, this delay leaves many wondering when broader recognition of the therapy’s potential will finally be realized. In the meantime, modern HBOT applications continue to develop, inspired by the foundational discoveries that still guide today’s practices and standards.