Tuesday, August 05, 2014

1870-1900: The Pneumatometer x

Hawke's Apparatus
Due to the perceived therapeutic benefits of pressure therapy, between 1800 and 1870 various apparatus's were invented to provide "pneumotherapy" for such conditions as asthma, throat edema, emphysema, bronchitis, or dyspnea caused by diphtheria(2, page 45)

If you were a physician at this time you saw before your own eyes the evolution of pressure therapy.  By 1903 pneumotherapy was mentioned in various medical books, although it was still "under-utilized."  Paul Louis Alexandre Tissier's, in his 1903 text, "Pneumotherapy: Including Aerotherapy and Inhalation Methods and Therapy," provides a detailed description of pneumotherapy. (1)

He expains that the machines available provided pressure changes upon the respiratory passages (1): 
  • By inspiration of condensed air (we now call it positive pressure)
  • By expiration into condensed air (what we now call PEEP)
And the following methods decrease pressure in the lungs (1):
  • By expiration into rarified air (what we now call negative pressure)
  • By inspiration of rarified air 
Withington's Apparatus
Tissier describes the following devices.  Most of them were used in the patients home mainly by the patient placing a rubber mask over his face, although some may also be used by physicians as spirometers or to provide artificial respiration.  (1)

1.  Hauke's Apparatus:  After a series of tests by Hawke from Vienna, it was introduced around 1870.  (3)It's basically a tank filled with water to supply pressure or rarified air upon expiration and inspiration as provided by a pump or bellows.  Rubber tubing connects from the tank to a rubber mask that fits over the mouth and nose, held in place by the patient. (1)

Hauke recommended using this to offset the "dyspnea caused by diphtheretic laryngitis in which it was not always successful."  It was also used successfully for pulmonary tuberculosis and emphysema.  The problem with this device is there was no way of measuring breaths given  (1)

2.  Waldenburg's Apparatus:  The flaws with the Hauke design were corrected by Waldenburg of Berlin.  The 1873 model consists of two reservoirs of sheet iron, and an inner and outer cylinder, with the inner cylinder gliding on the outer one.  (1)

A cap on the outer cylinder is 10 cm in height and wider than the outer cylinder.  The inner cylinder is moved up and down by means of weights and pulleys.  "Water is poured into the apparatus so that, when the inner cylinder is forced down into the outer cylinder, the apparatus is filled to the brim, the cylindrical cap at the top of the outer cylinder being destined to receive the water that overflows when the inner cylinder descends."  (1)

Graduated scales allow for measuring volume.  A rubber hose is connected to a spun metal mask cushioned with rubber.  Both positive and pressure breaths can be given with the device, and the breaths can be measured "regularly and accurately."  In fact, the device could also be used as a spirometer to measure lung volumes.  (1)

Figure 25 --Apparatus of Finkler and Kochs
Air could be moistened and warmed by adding a wolffe bottle.  Tissier also notes that the "apparatus has been deemed worthy of detailed description, as it has probably been used more frequently than any other."  (1)

The apparatus was later modified by Cube, Weil, Schnitzler, and other folks you'd be familiar with if you were an RT in this era. (1)

As you can see by figures 21 and 22, some of these wouldn't be applicable for home use, and may even be too bulky and expensive even for hospital use.  

Apparatus of Finkler and Kochs:  "With this apparatus (Fig. 25) condensed air is forced into the lungs during inspiration, expiration being assisted by withdrawal of air from the lung."

Inspiration is basically caused by positive pressure, and expiration occurs by negative pressure or suction.  

The device can also be used as a spirometer to measure forced expiratory capacity, or "the quantity of air that can be expired after the fullest possible inspiration."

Beidert's Instrument:  This is an interesting device that's designed similar to a musical instrument called the harmonica, "to one extremity weights are affixed...  it's walls are made of leather, air tight, and have a necessary strength to maintain their original form against overpressure of air."

The machine is operated this way:  "The machine is placed upright on the margin of a table, so that the tube will be in a groove cut into the wooden base, and the desired quantity of (iron) weights is fastened to the upper cover of the bellows. If the upper end is turned down, the weights will sink and the bellows will fill itself with air. The bellows is then turned back, while the patient compresses the rubber tube with his fingers until he is ready to inhale through the mouthpiece attached; he then gradually inhales the air as the weights compress the bellows. While the patient expires into the free air the bellows is filled again by turning, and the operation continued in this manner indefinitely."

Pressure can also be applied in the following manner:   For expiration into rarefied air, the tube is compressed and the bellows turned weights downward; applying the tube to the mouth, the air passes from the lungs into the partial vacuum produced by the expansion of the bellows. The bellows filled with the expiratory air is emptied by turning, while the patient inspires air at the atmospheric pressure, and the operation is repeated."

Frenkel's Apparatus
It appears like it would be a lot of work, but if it makes a person feel better, then it might be worth the effort.  

Frenkel's Apparatus:  If you think the figure to the right looks like an accordion, you would be... wrong.  You sit with the apparatus on your lab, and between your palms.  You place the mask over your mouth and nose. 

The air is rarified when you pull the accordion out, and when the device is compressed the air is condensed.  So pulling the "accordion" out will cause expiration, and pushing it in will cause inspiration.  

In compliance with all pressure devices since the Hauke Apparatus, "on the margin of the apparatus is a centimetric measure to measure how many centimeters the wooden disks are separated or brought together." It is by this means that volumes can be measured.  
Figures 21 and 22

So it appears to have been a very interesting device, and perhaps the simplest and easiest to use.  It could easily be used at home by the patient whenever needed.  The device can also be used at a doctor's office or hospital for artificial respiration in the case of asphyxia or poisoning, and could be used as a spirometer.  

Next week I will describe a few more of these devices.  

References:
  1. 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. 
  2. Minnesota State Medical Society, "Transaction of the Minnesota State Medical Society," 1886, St. Paul, H. M. Smyth Printing Co. 
  3. 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
  4. Foster, Frank, editor, "Practical Therapeutics," Volume I, 1897, New York, Appleton and Co., page 19

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