The
History
of
Hyperbarics:
The word ‘hyperbaric’ literally means ‘high pressure’. The use of high
pressure (i.e. pressures higher than normal atmospheric pressure) and it’s use
in medicine is often viewed today in the United States as being somewhat new and
controversial. However, the concept of Hyperbaric Medicine has been in existence
since as early as 1662.The industrial revolution, when bridge and tunnel builders were working in compressed air, saw a further great development in hyperbaric chambers. It was at this time when Paul Bert reported that nitrogen bubbles were forming in tissue during rapid decompression (1876) and was implicated in “The Grecian Bend”.
Since the latter part of the twentieth century hyperbaric medicine has gained most of its recognition for the treatment of certain mainstream medical conditions specifically related to the diving industry, including decompression sickness and air embolism.
Hyperbaric
Beginnings:
The emergence of undersea and hyperbaric medicine is closely linked to the
history of Diving itself, although it would not be until Robert Boyles’
experiments in 1670 that the first trace of the study and causation of DCI would
begin.Early breath-hold divers, dating back more than 5000 years, were confined to work in waters less than 30metres (100feet) deep, these “first” divers performed tasks such as harvesting food, coral, sponges and pearl as well as the odd ship salvage, a task which still captivates the attention and imagination of most modern age divers. One of the earliest recorded exploits of divers is that of the Greek Scyllis, as told by the Greek historian Herodotus:
Whilst engaged in a sea battle, scyllis was taken prisoner aboard the Persian King Xerxes’s ship. Learning of an attack on the Greek flotilla, he seized a knife and jumped overboard. The Persians could not find him and presumed he had drowned. Scyllis remained hidden and later surfaced under cover of darkness and made his way amongst Xerxes’ ships, cutting each ship loose from its moorings; he accomplished all of this by breathing through a hollow read. Then he swam nine miles to rejoin his Greek comrades.
The Honourable Robert Boyle was an Irish Natural Philosopher (chemist, physicist, and inventor), noted for his work in physics and chemistry. Born to the richest man in Great Britain and receiving a priveleged education at Eton and throughout Europe, Boyle is regarded today as the first modern chemist.
Robert
Boyle:
Robert Boyle made important contributions to both physics and chemistry and
is best known for a law of physics experienced by all divers describing the
behaviour of an ideal gas. Boyles Law appears in an appendix his work “New
Experiments Physio-Mechanical, Touching the Spring of the air and its Effects”
(1660).Boyle’s law states that at constant temperature, the absolute pressure and the volume of gas are inversely proportional. As pressure increases, the gas volume is reduced; as pressure is reduced, the gas volume increases. This law, especially when combined with the work of Gay-Lussac and Charles produce the General Gas Law; invaluable to Diving and Recompression Chamber operations.
This 1660 text was the result of three years of experiments conducted with the help of scientist Robert Hooke. Using an air pump designed by Hooke, Boyle was able to discover a series of important facts, such as sound not travelling in a vacuum, a flame requiring air and investigating the “elastic properties of air”.
Boyle also first described the effects of Decompression Illness when in 1670 he used the vacuum pump to decompress a snake (undoubtedly somewhat rapidly) and reported: “I once observed a viper furiously tortured in our exhausted receiver… that had manifestly a conspicuous bubble moving to and fro in the waterish humour of one of its eyes.”
Edmond
Halley
and
the
history
of
Hyperbaric
Medicine:
Halley, born of a wealthy soapboiler in Haggerston, London studied at St.
Paul’s School before graduating from Queens College, Oxford. Whilst still an
undergraduate, he published his papers on the solar system and sunspots. Further
study whilst in St. Helena led him to publish two papers, the first “Catalogus
Stellarum Australium” included details of 341 stars; the second, published in
1686, concerned trade winds, monsoons and established the relationship between
barometric pressure and height above sea level.
In 1690, Halley developed plans for a diving bell, in which the atmosphere was replenished by way of weighted barrels of air sent down from the surface. In a demonstration of his apparatus, Halley and five companions dived to 60feet in the River Thames, and remained there for over one and a half hours. Halley’s bell was likely to be very heavy and possibly of little use for actual salvage work, although he did make improvements to his bell over time, later extending his underwater exposure time to over 4 hours.
Halley, of course later went on to have a comet named after him after famously predicting the return of a comet previously seen in 1456, 1531, 1607 and 1682. The comet returned in 1758 and has since been known as Halley’s Comet.
Henshaw
&
‘The
Domicilium’
In 1662, the British Clergyman Henshaw started over 340 years of
Recompression Chamber history when he built his “Domicilium”, driven by organ
bellows, with valves to control the flow of air, this sealed chamber was used to
create both Hyper (above normal) and Hypo (below normal) – baric
conditions.
Despite lacking any scientific basis for his theories, Henshaw believed that
patients suffering from acute conditions would benefit from increased air
pressure, whilst those suffering more chronic ailments would profit from a more
rarefied environment, “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
prevention of most affections of the lungs.”. At this stage, air had yet to be
broken down into its constituent gases, therefore, Henshaw’s pioneering patients
were only exposed to increases of pressure (such that can be achieved with organ
bellows) without the other vital ingredient – Oxygen.
Hyperbarics
in
France
during
the
19th
Century:
In the 1830′s, France led the new fashion in Hyperbaric Medicine. Hyperbaric
chamber exposures of between 2 and 4 atmospheres absolute were stated to
increase the circulation to the internal organs, improve the cerebral blood
flow, and produce a feeling of well being.Junod (1834) first made these observations, and they were taken up avidly by his colleagues, Tabarie and Pravaz. In 1837, Pravaz built a large hyperbaric chamber using it to treat a variety of ailments. The chambers were promoted and used specifically for pulmonary diseases, including tuberculosis, laryngitis, tracheitis and pertussis, as well as apparently unrelated diseases such as deafness, cholera, rickets, menorrhagia and conjunctivitis.
Fontaine (1877) developed the first mobile hyperbaric
operating theatre and by this time hyperbaric chambers were available in all
major European cities. Interestingly, there was no general rationale for
hyperbaric treatments and as a result, prescriptions varied from one physician
to another. In those days, no methods were available to estimate the partial
pressure of oxygen in blood, which at 2 ATA of air is about double that at sea
level. In comparison, if pure oxygen is breathed at 2 ATA, the partial pressure
of oxygen in the arterial blood is twelve times higher than normal.The chamber was recommended to facilitate the reduction of hernia, and for patients with asthma, emphysema, chronic bronchitis and anemia. Twenty-seven operations were performed within a 3 month period in this chamber. Success was so great that a large hyperbaric surgical amphitheatre which would hold 300 people was planned, although never actually came into being. Fontaine had an accident whilst at the Pneumatic Institute which resulted in his death, the first physician martyr to Hyperbaric Medicine.
Williams, in the British Medical Journal of 1885, made a comment, which would be thought by many to be applicable today, “The use of atmospheric air under different degrees of atmospheric pressure, in the treatment of disease, is one of the most important advances in modern medicine and when we consider the simplicity of the agent, the exact methods by which it may be applied, and the precision with which it can be regulated to the requirements of each individual, we are astonished that in England this method of treatment has been so little used”.
Hyperbarics
in
the
Americas
1860-1940:
The first hyperbaric chamber on the North American continent was constructed
in 1860 in Oshawa, Ontario, Canada. The first such chamber in the United States
was built by Corning a year later in New York to treat ‘nervous and related
disorders’.The Chamber that received the most publicity and was the most actively used, was that of a Dr Cunningham in Kansas City during the 1920′s. Cunningham first used his chamber to treat the victims of the Spanish influenza epidemic that swept across the USA during the closing days of the First World War. Cunningham had observed that mortality from this disease was higher in areas of higher elevation, and he reasoned that a barometric factor was therefore involved. He claimed to have achieved remarkable improvement in patients who were cyanotic and comatose. One night however, a mechanical failure resulted in a complete loss of compression and all his patients died. This tragedy was a sobering lesson but ultimately did not deter Dr Cunningham. His enthusiasm for hyperbaric air continued, and he started to treat diseases such as syphilis, hypertension, diabetes mellitus, and cancer. His reasoning was based on the assumption that anaerobic infections play a role in the etiology of all such diseases.
In Cleveland, in 1928 Cunningham constructed the largest chamber ever built – five stories high and 64 feet in diameter. Each floor had 12 bedrooms with all the amenities of a good hotel. At that time it was the only functioning hyperbaric chamber in the world.
Dr Cunningham was repeatedly requested by the Bureau of Investigations of the American Medical Association (AMA) to document his claims regarding the effectiveness of Hyperbaric Therapy.
Apart from a short article in 1927, Cunningham made no efforts to describe or discuss his technique in medical literature. He was eventually censured by the AMA in 1928 in a report that stated: “Under the circumstances, it is not to be wondered that the Medical Profession looks askance at the ‘tank treatment’ and intimates that it seems tinctured much more strongly with economics than with scientific medicine. It is the mark of the scientist that he is ready to make available the evidence on which his claims are based.”
Dr Cunningham was given repeated opportunities to present such evidence but never did so. The Cunningham chamber was dismantled for scrap in 1937, which brought to a temporary end the era of Hyperbaric Oxygen Therapy for medical disorders.
Drager, who in 1917 devised a system for treating diving accidents, first realized the potential benefits of using oxygen under pressure for the treatment of decompression sickness. For some unknown reason, however, Drager’s system never went into production. It was not until 1937 – the very year that Cunningham’s “air chamber” hotel was demolished – that Behnke and Shaw actually used hyperbaric oxygen for the treatment of decompression sickness.
The
Development
of
Hyperbaric
Medicine
in
the
1950′s
&
1960′s:
A flurry of interest in therapeutic hyperbaric medicine
was fostered by Dr I. Boerema, who, while in Amsterdam in 1956, reported
hyperbaric oxygen (HBO) as an aid in cardiopulmonary surgery, particularly for
congenital conditions such as tetralogy of Fallot, transposition of great
vessels, and pulmonic stenosis. A colleague of Boerema’s, W. H. Brummelkamp,
also interested in hyperbaric medicine, discovered in 1959 (and subsequently
published in 1961) that anaerobic infections were inhibited by hyperbaric
therapy. Meanwhile, Boerema had published an article, “Life without blood,” a
report of fatally anemic pigs treated successfully with volume expansion and
pressurised hyperoxygenation. Boerema often is credited as the father of
modern-day hyperbaric medicine.In 1962, Smith and Sharp reported the enormous benefits of HBO in carbon monoxide poisoning. International interest thus was rekindled, and HBO therapy was thrust into the modern era. Hyperbaric units subsequently were built at Duke University, New York Mount Sinai Hospital, Presbyterian Hospital and Edgeworth Hospital in Chicago, Good Samaritan in Los Angeles, St. Barnaby Hospital in New Jersey, Harvard Children’s Hospital, and St. Luke’s Hospital in Milwaukee. Further chambers were installed in numerous international sites.
Modern
Day
Hyperbaric
Therapies:
The benefits of hyperbaric medicine subsequently were observed for
split-thickness skin graft acceptance, flap survival and salvage, wound
re-epithelization, and acute thermal burns. These studies lent credibility to
the therapeutic employment of HBO therapy. This fostered the establishment of
organized scientific congresses and societies such as the International Congress
on Hyperbaric Oxygen and the Undersea Medical Society. Unfortunately, as the
availability of hyperbaric medicine chambers increased, the indiscriminate and
inappropriate use of the chamber for a variety of medical conditions by
practitioners searching for a “cure-all” therapy resulted in a backlash from the
scientific society, once again tarnishing the credibility of hyperbaric
medicine. As a result, by the late 1970s, the Undersea Medical Society had
formulated guidelines for the use of hyperbaric therapy.
Researchers conducting wound-healing studies continued
to try to take advantage of the angiogenic properties of increasing oxygen
gradients resulting from hyperbaric therapy. Foot wounds from diabetes,
radiation ulcers, and other ischemic wounds have been manipulated and
successfully treated with HBO. Prospective blinded randomized trials and
well-executed laboratory studies continue to further define the role of
hyperbaric therapy in medical therapeutics.The most recent and most significant documented advances with Hyperbaric Medicine, have emerged with the utilization of high tech investigation including isotopic tracers with Magnetic Resonance Imaging (MRI) and Single Photon Emission Computed Tomography (SPECT).
MRI and SPECT performed as a pre and post hyperbaric evaluation have provided valuable insights into the mechanisms and actions of Hyperbaric Medicine through oxygenation. Conditions that have previously been considered to have a poor prognosis, including brain injuries, stroke and neurological based conditions, have been greatly improved with Hyperbaric Medicine and continue, today, to be among the areas of research.
sumber : New Leaf Hyperbarics
http://newleafhyperbarics.comSourced from London Diving Chamber
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