Hyperbaric (adjective) - Of or involving a gas at a pressure greater than normal
Technology and medicine have always gone hand in hand with one aiding the
other. The eureka of intertwining physics, biology, and medicine by developing
innovative technology, can aid the healing process of patients without the intake of
drugs. The principle of pressure and gases was used to find a way to increase the
oxygen dissolved in the blood of humans. The first document of hyperbaric therapy
was found by Nathaniel Henshaw in 1662. From then on, alternations were made
and used in everyday hospitals. Currently, in Thailand, 8 HBO Hyperbaric
oxygenation (HBO) clinics exist with Pinklao Hospital owning the largest chamber.

Hyperbaric medicine utilizes Henry’s law of pressure and 100% oxygen to aid
patients. Henry’s law states that the amount of dissolved gas in a liquid is directly
proportional to its particle pressure above the liquid. By increasing the ambient
pressure around the patient to a pressure that is greater than sea level (by placing
them in a hyperbaric chamber) while they are breathing 100% oxygen, a more
significant amount of oxygen can be taken in by the lungs and dissolved in the
patient's blood. The pressure used is usually around 2 to 3 atmospheres absolute.
Therefore, increasing the oxygen in the bloodstream which can be used by different
organs in the body to heal tissues and fight infections.

In 1662, a British physician Nathaniel Henshaw first utilized hyperbaric
therapy. This was done by placing patients in a pressurised steel container.
However, after the first experiment, concerns about breathing compressed air arose.
Thus, initiating “hyperbaric oxygenation” (HBO). After the discovery in 1789, the
work of Lavoisier and Seguin suspected there were toxic side effects surrounding
breathing in concentrated oxygen which targeted the nervous system. However, this
was not verified until almost 100 years later. In 1887, Paul Bert documented the toxic
side effects of hyperbaric oxygenation on the central nervous system which
appeared as seizures. Even with the documentation, his findings took a while to
establish in the community. Almost half a century later, successful uses of this
treatment were documented. In 1937, Behnke and Shaw used HBO to cure
decompression sickness. Then in 1955, Churchill-Davidson used HBO to to
potentiate the effects of radiation therapy for cancer patients.

Before this treatment could be applied to hospitals, a variety of vigorous
experiments and testing has to be completed. has been done. Mostly these tests
have been done on animals with around 30 animal studies done, with around 3000
animals being tested. Some of these tests were done on human volunteers involving
around 58 people. All of the human studies involved patients who had minor and full
blisters or partial burns. For example, the first study was done by Hammarlund in
1991. Healthy male volunteers who had been wounded by U.V. radiation or skin
blistering on the forearm were sealed in the hyperbaric chamber to be tested.

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Hammarlund tested the time from which the volunteers were wounded and applied
the treatment at 1.5h, 10.5h, and 21.5h after inflicting the wounds. For all these
times, the wound healed faster after the use of HBOT and showed beneficial effects
on the superficial dermal lesion. Oedema (build-up of fluid which causes tissues to
swell) and Exudation (oozing of built-up fluid) were decreased. Thus showing that
HBOT treatment works to help heal wounds faster, but the rate of epithelialization
(reforming skin) was not accelerated. Later on, HBO technology was utilized to treat
many different illnesses such as Carbon Monoxide poisoning, Tissue infections,
Acute thermal burn injuries, severe anaemia, Gas embolism, and more.

Nowadays, modern hospitals use HBO to help treat many illnesses. HBOT
(Hyperbaric oxygen therapy) has been shown to accelerate tissue repair and reduce
infection risk. The discovery of HBOT has saved millions of people, but with every
treatment, there are some risks to modern HBOT, such as lung damage or fluid
damage within the ear to name some (due to equalisation issues regarding the
membrane within the ear canal). Overall, the advancements in technology and the
discovery of HBOT are ever-changing and will almost certainly improve over the
years. This eureka moment will be remembered by many, as there are many
versatile uses of hyperbaric oxygenation technology across the scope of medical
illnesses.