Turning a solution into a mist is a good means of getting medicine down into the lungs, where it's needed and can be of use. Nebulizers were basically believed to break a solution into atoms, and thus the first nebulizers were often referred to as atomizers. The process of creating a mist was thus termed atomization.
Some of the first nebulizers were described by John M. Scutter in his 1867 book "On the use of medicated inhalations in the treatment of diseases of the respiratory organs. The book was one of the first specifically dedicated to inhalation therapies, including devices to deliver it and the medications. If the respiratory therapy profession existed back then, it would have been a must read.
Nebulizers basically work based on the Bernoulli Principle. The idea comes from the observation that when water hits a rock it creates a mist that can be inhaled. Daniel Bernoulli published a book in 1738 where he described that a similar effect could be created by forcing water through a narrow tube. The faster water flows through a tube, the less the lateral pressure will be. Thus, in nebulizer air is forced through a narrow tube, and fluid is entrained into the narrow opening. The fluid is basically sucked in due to the negative sidewall pressure, and turned into a mist to be inhaled. (2, page 61)
So anyway, the following are the first nebulizers according to Scutter. I will allow him to do the describing. (see pages 26-36):
Elsberg's Nebulizer |
Sales-Giron's Nebulizer |
3. Dr. Mackenzie's Nebulizer: "The apparatus of Dr. Mackenzie is a very good one. The piston is drawn back by a wheel and rack at its upper part, and is forced down by a circular spring which surrounds the cylinder. The apparatus is filled with liquid by a funnel in its top, and all the spray, except that which is inhaled, passes back into the apparatus. He claims the following advantages for it: 1. Its simplicity, requiring only a few turns of a handle to set it in operation. 2. The extremely fine state of subdivision which it effects. 3. The uniform pressure exerted. 4. The fact that the Waste liquid returns into the apparatus. 5. The ease with which it can be taken to pieces and cleaned."
Dr. Seigle's Inhaler |
4. Dr. Seigle's Inhaler: "The third form of apparatus is that of Dr. Seigle, and is preferable to the others, for its simplicity and because it is automatic. The best reason for preferring it, however, is, that its price is such as to bring it within the means of any patient, as it is furnished through the druggists for$5,00, and its construction is so simple, that it is readily operated by any one." The inhaler (or nebulizer) is designed so that steam provides the flow that makes the bournoulli principle work, and in this way the operator doesn't need assistance to create a mist. The device simply sits on a table and the patient can enjoy the mist, and hopefully relief in breathing. I will describe this inhaler in greater detail in a later post.
So these are your basic nebulizers of the 19th century. It's basically what you had to deal with until the 1930s when electricity became available.
References:
References:
- Scudder, John Milton, " On the use of medicated Inhalations in the treatment of diseases of the respiratory organs," 1867, Cincinnati, 2nd edition, Moor, Wilstach, and Baldwin
- Wyka, Kenneth A., Paul Joseph Mathews, William F. Clark, "Foundations of Respiratory Care,"
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