Wednesday, March 1, 2017

1836: The beginning of pressure therapy and Tabarie's Sphere

G
Galileo (1564-1642) was perhaps the first to consider the idea that air had weight.  Yet it was his pupil, Evangelista Toricelli (1608-1647), who proved the existence of atmospheric pressure.  From there, it didn't take long for ideas to evolve for using changes in atmospheric pressure as therapy for various diseases, such as lung ailments  (3, page 52)

Tabarie's Sphere (3, page )
The major question Toricelli set out to answer was:  Why is it that water is prevented from being pumped up higher than 32 feet?  He performed a test, and proved the answer was due to the weight of the air, or atmospheric pressure.

Apparently influenced by folks who described the benefits of climate change or high altitudes, Nathaniel Henshaw (1628-1673) was the first to create a chamber for artificially raising or lowering atmospheric pressure so that it could be used to help people feel better.  Henshaw's called his chamber the "Domicilium," which was basically a "sealed room," that was attached to a "pair of large organ bellows."  This chamber is now considered the first hyperbaric chamber.  (5, page 1)

According to Tissier, the "chamber was built of masonry and supplied with doors and windows that could be closed hermetically.  It communicated with two bellows (the organ bellows) provided with valves, which worked in opposite directions, in such a way that it was possible, at will, to obtain compression or rarification of air." (3, page 55)  

Here we require a couple definitions:

1.  Compressed Air:  This was the original term used to describe increases in atmospheric pressure.  It's air with a larger volume of oxygen than ordinary air.  It is positive pressure. 

2.  Rarified Air:  This was the original term used to describe decreases in atmospheric pressure.  This is air that contains less oxygen that normal room air.  It is negative pressure. 

So, basically, Henshaw's organ bellows, when pressed, forced air into the chamber, and therefore increased the atmospheric pressure inside.  When the bellows were relaxed, pressure was decreased inside the chamber.  Future chambers, and portable apparatus's, would apply a similar technique to compress and rarify air.  

Other than Henshaw's work, there's little evidence pressure changes were considered for therapeutic use for diseases until the 1750s.  Yet by 1800 there was such strong speculation for the therapeutic use of pressure therapy that the Royal Society of Haarlem opened the idea up to a competition to determine "The influence of condensed air on animal and vegetable life."  Yet it was to no avail. (1, page 43)

However, the idea continued to circle the profession, and Sir John Sinclair suggested, based on his observations of the effects of pressure on animals, that changes in pressure may have therapeutic benefits for humans.  (1, page 43

Among the first to come to the challenge were Emile Tabarie and Junod.  In 1833 Tabarie discussed the topic with the Parisian Academy of Science, (2, page 19and in 1835 Tabarie performed the first experiments.

Junod reported that when the "natural pressure of the atmosphere is augmented by one-half, the following effects will be observed:"
  1. Disagreeable sensation of pressure in the ears, subsiding as equilibrium is re-established
  2. Respiration is Facilitated.  The inspiration becomes deeper and less frequent
  3. Circulatory changes occur
  4. Functions of digestive apparatus are stimulated
  5. Secretions of salivary glands and kidneys are very profuse
There were various theories to account to the perceived benefits of pressure changes on breathing. The pressure seems to open and keep the alveoli open to better receive the next breath.  The vessels of the body appear to be compressed, which stimulates the pulse to increase so it is "full and easily compressible. the caliber of the superficial veins is diminished, and the lumen may even become completely obliterated, so that the blood on its way back to the heart courses through the deeper veins."  (3, page 72)

If this is true, it was determined that the same effect must occur to the pulmonary vessels, and this results in "the quantity of venous blood contained in the lungs (to) diminish; and this probably explains why a much greater quantity of air can be drawn into the lungs at each inspiration that is possible under normal pressure. (3, page 72)

"Further, if an increase in the density of the air tends to diminish the caliber of the veins, it follows necessarily that a greater quantity of blood will enter the arterial system and more blood will also reach the principal nerve-centers; especially those in the brain, because the latter is protected from the direct pressure of the atmosphere by the resistant bony calvarium. The cerebral functions are accordingly enhanced, the imagination becomes more active, and in some persons there is a peculiar exaltation which stimulates drunkeness." (3, page 72)

By 1838 Tabarie had performed a variety of tests to study the effects on pressure changes on the various parts of the body, all except for the head. He studied the effects of both condensed and rarified air. By his experiments Tabarie determined that condensed air "retards the action of the heart and steadies the rhythm. This effect is very slight and may not be noticeable under normal conditions, but becomes quite evident in disease." (3, page 72)

Tabarie ultimately devised a chamber, or sphere, that was made of iron that allowed up to twelve people to enjoy the benefits of pressure changes.  "He advised sittings of two hours duration with an increased pressure of from one-half to two-thirds of an atmosphere.  Bertin, who used the spheres, reported the cure of fifteen cases of uncomplicated emphysema, and ninety-two cases of nervous and catarrhal asthma with associated emphysema.  Air chambers, cumbrous, expensive and not portable, were thus far used." (1, page 44)

Various pneumatic chambers were devised and used around this time, with a variety of shapes being used. However, they were all based on the design of Tabarie's Chamber. They contained two pipes, one for for supplying the air and connected to a hydraulic compressor operated by steam.  The other pipe was for ventilation.  

References:
  1. Minnesota State Medical Society, "Transaction of the Minnesota State Medical Society," 1886, St. Paul, H. M. Smyth Printing Co.
  2. Foster, Frank, editor, "Practical Therapeutics," Volume I, 1897, New York, Appleton and Co., page 19
  3. Tissier,Paul Lewis Alexandre, edited by Solomon Solis Cohen, "Pneumotherapy: Including Aerotherapy and inhalation methods," volume X, 1903, Philadelphia, P. Blakiston's Sons and Co., pages 296-224.  If the profession of respiratory therapy existed in their era, we would be reading their books.  However, as it was, their books were written for the medical profession. All of the material from this post is from Tissier's book unless otherwise noted in the above paragraphs. Tissier page 72
  4. Rose, A., "Treatment of Disease of Respiration and Circulation by the Pneumatic Method," New York, The Medical Record: A Weekly Journal of Medicine and Surgery, Edited by George F. Shrady, M.D., Volume 10, Jan. 2, 1875 to Dec. 25, 1875, New York, William Good and Co., page 577
  5. Clarke, Dick, "History of Hyperbaric Therapy," Chapter 1 of the book, "Physiology and Medicine of Hyperbaric Oxygen Therapy," 2008, Philadelphia, Saunders, page 1-2
  6. Picture is from an advertisement placed in the Medical Press of Western New York, volume II, No. 6, June, 1887, Roswell Park M.D., editor, New York, Bigelow Brothers, page 338

No comments:

Post a Comment