1860: Salter disproves ancient asthma theories

Dr. Henry Hyde Salter was among the first physicians to believe that diseases ought to be defined based on personal experiences with the diseases, observing patients, and studying autopsies, as opposed to speculation.  Later physicians said it was this technique that made him the most famous asthma doctor of his era.  

In the opening chapter of his 1960 book "Asthma: Its Pathology and Treatment" he put to rest any theories about asthma that didn't support modern evidence. While he shunned the humoral ideas of ancient writers, he also shunned the bronchitic theories of the famous Dr. Robert Bree  who's believed asthma was caused by some peccant matter entering the lungs

Salter said that Bree was so convincing, and had obtained such a large following, that he had to dedicate almost an entire chapter to disproving his theories.

However, in the end, Dr. Salter said Dr. Bree's theory was disproved simply by the invention of the stethoscope.  He said if Bree had access to a stethoscope he would have easily heard the wheezes caused by narrowed air passages due to neurosis, and would have heard that the wheezes persist even after mucus is expectorated, as opposed to before.

One of the reasons Dr. Bree's ideas were so well accepted was because they were more in line with the Hippocratic doctrine, which was still well accepted by many prominent physicians when Bree first wrote his 1798 book "A Practical Inquiry into Disordered Respiration."

Since Hippocrates, many asthma experts believed asthma was caused by an imbalance of the four humors. Salter doesn't deny...

..."that in some cases the exciting cause of the attack is humoral; but what I would deny is, that the humoral derangement has any higher place than that of an exciting cause; and what I would insist upon is, that the heart and core of the disease is nervous; that the essential peculiarity of the asthmatic is a vice in his nervous system, a peculiar morbid irritability of it, whereby a certain portion of it is thrown into a state of excitement from the application of stimuli which another person would produce no effect at all, or a very different effect." (1, page 25)

Salter disproved the idea that congestion, or phlegm, or mucus, was the cause of asthma, because the attack usually ends with the expectoration of phlegm. He wrote:

"We admit the fact to be true, but doubt very much the correctness of the inference; at least it is certain that, in ordinary bronchitis, enormously greater accumulations of mucus take place with comparatively few signs of general obstruction. We think this position must be admitted by any unbiased observer; and it is, in our opinion, fatal to this theory. (1, page 25)

Given the tools available to Salter, wasn't hard for him to disprove old asthma theories in favor of science. He went on to prove that asthma was nervous and spasmotic, and was so convincing that his ideas were referenced by nearly every author on asthma for the next 50 plus years.

References:

1. Salter, Henry Hyde, "Asthma: It's Pathology and Treatment," 1864, Philadelphia, Blanchard and Lea

RT Cave Facebook Page
RT Cave on Twitter

1815: Parry Shares his wisdom of asthma

Dr. Caleb Hillier Parry, in his 1815 book "Elements of Pathology and Therapeutics," gives us an excellent idea of what physicians knew about asthma at that time.  Through his thoughts relayed through this book we gather answers to all our questions on the subject.  

1.  What leads to a fit of asthma?  In patients who are subject to spasmodic asthma, fits of that disorder often begin with a violent coryza, in which the eyes become red and watery, and all the symptoms of a cold in the head are observable. After a few days, or sometimes even only hours, these symptoms suffer some degree ofalleviation, and the malady proceeds to the bronchia, occasioning all the well-known signs of spasmodic asthma. What, then, is this state in the bronchia, but an affection of the mucous membrane of those cells, exactly similar to that which had previously existed in the same membrane in the nose?  (1, page 196)

2.  Is asthma spasmotic in nature? It may, however, be said, that asthma is a spasmodic affection, depending on causes acting on the mind, etc, and returning at regular periods. (1, page 197)

3.  What are the exciting causes of asthma? The disease called spasmodic asthma is brought on by almost every thing which increases the action of the heart, and which stimulates and fills the vessels of the mucous membrane itself. Thus it is produced by intense heat, by lightness of air, by exercise, by full meals, by stimulating drinks, and by certain effluvia, as those of hay, whether new or old, of sealing wax, and other burning substances, and of ipecacoanha, while powdering, or even sometimes when a paper or bottle of it is opened in the same room with the patient. Of the operation of all these causes I have seen several examples; and similar cases might doubtless be found in the writings or experience of other medical men.   (1, pages 197-198)

4.  What specifically is asthma? These facts are convincing proofs of such a preternatural fulness of the vessels of the mucous membrane of the bronchia, as to impede free inspiration, and to produce all the symptoms of spasmodic asthma. (1, page 198)

5.  How is asthma relieved?  Asthma is relieved by gently open bowels, by heavy air, by inhaling that which is cold, and by cooling drinks. It diminishes, as soon as mucous secretion begins to take place; and is more speedily and effectually relieved by spitting of blood. (1, page 198)

6.  Is asthma nervous? We see the absurdity of assuming asthma to be a nervous disease, produced by a spasmodic constriction of tubes, in the parietes of which no muscular fibres have ever been demonstrated, and no equivalent power of producing such an effect has ever been proved. (1, page 200)

7.  What exactly occurs during an asthma attack? Spasmodic asthma is rarely accompanied with much preternatural heat, though the pulse is sometimes quick. The oppression of breathing consists of a general sense of constriction rather than pain, which resists inspiration, and which the patient in vain attempts to overcome, by employing all the muscles which assist in elevating the ribs, and therefore expanding the thorax. It is, however, apposite to remark, that, in patients in whom the disease is habitual, it sometimes runs into the state of bronchitis, and has all the marks of an acute affection of that kind. (1, pages 200-201)

8.  Can the cure of other ailments cause asthma? Fits of spasmodic asthma are not uncommon after the cessation of gouty paroxysms! I have often seen various thoracic affections, as pulmonary consumption, asthma, inflammation of the heart, or hydrothorax, arise from the spontaneous or artificial cure of ulcers, perpetual blisters, or fistula? (1, page 383, 386)

9.  Can asthma kill? A gentleman, formerly affected with frequent fits of epilepsy, ceased to suffer them on the appearance of gout, which often recurred, and a paroxysm of which was immediately followed by a sudden attack of spasmodic asthma, which, in twenty minutes, proved fatal.

10.  Can other ailments lead to a cure of asthma? That kind of chronic bronchitis, which is often called asthma humidum, is frequently relieved by the coming on of oedema in the lower extremities. I have also known dyspnoea and cough, of long standing, entirely cease on the appearance of ascites.

Bottom line:  Parry believed that asthma was essentially inflammation of the air passages of the lungs that lead to spasms of these passages.  In other words, he was a proponent of the bronchitic theory of asthma. 

RT Cave Facebook Page
RT Cave on Twitter

1815: Parry supports bronchitic theory of asthma

Caleb Hillier Parry (1755-1822)

Much like the great London physician William Heberden, Dr. Caleb Hillier Parry of Bath was known for taking copious nots. Perhaps he used these notes when describing asthma in his 1815 book "Elements of Pathology," (1, page 372)

He was born in Bath in 1755 and received his general education at the academy of Warrington, and his medical and philosophical education at the schools of Edinburgh and London.  (2, page 372)

William Heberden was the first to describe Angina Pectoris in a speech he gave to the Royal College of Chest Physicians in 1768.  In 1772 his speech was published in The Transactions of the Royal College.  While he described the symptoms of chest pain accurately, Heberden did not know chest pain was caused by a diseased heart.

A few years later, in 1786 a friend of his by the name of Edward Jenner, the same man who earlier had discovered the world's first vaccination, said that angina pectoris was caused by "ossification," or hardening of the coronary arteries, or the arteries that deliver blood to the heart.  In a letter to Dr. Heberden, he said that without the right amount of blood, the heart could not perform its function of pumping blood through the vessels of the body.  (2, page 372)(3, pages 37-38)

Jenner shared his knowledge on the subject with his friend Dr. Parry.  Parry, in turn, communicated what Jenner learned about the subject, plus some insights of his own, with the medical community through his 1797 book "An Inquiry into the Symptoms and Causes  of Syncopy Anginosa, Commonly Called Angina Pectoris."  (2, page 372)(3, page 37)

This work was well received by the medical community. It was through this book that Caleb Parry became the first person to suggest that the way we live, and the foods we put into our bodies, may lead to disease, particularly angina pectoris. He suggested regular exercise and the avoidance of fresh meat.  (2, page 372)(3, page 38)

While "Angina Pectoris" was well received, his most famous work by far was "The Elements of Pathology," which, according to The Gentleman's Magazine:

This exhibits a great system of original and unexampled depth of observation, accuracy of conclusion, and abundance of fact and illustration; it may truly be considered as an almost unparalleled example of great originality and capacity.

It was in this book that he shared, among other things, his knowledge on the subject of asthma.

In patients who are subject to spasmodic asthma, fits of that disorder often begin with a violent coryza, in which the eyes become red and watery, and all the symptoms of a cold in the head are observable. After a few days, or sometimes even only hours, these symptoms suffer some degree of alleviation, and the malady proceeds to the bronchia, occasioning all the well-known signs of spasmodic asthma. What, then, is this state in the bronchia, but an affection of the mucous membrane of those cells, exactly similar to that which had previously existed in the same membrane in the nose? (4, page 196)

It may, however, be said, that asthma is a spasmodic affection, depending on causes acting on the mind, &c. and returning at regular periods. (4, page 197)A

A little over a century later, Orville Brown summed up Parry's view of asthma this way:

Parry suggests that engorgement of the mucous membrane of the bronchi produced such tumidity of it as to mechanically interfere with the passage of the air. (4, page 32)

In other words, like Robert Bree, Parry was a supporter of the bronchitic theory of asthma.  He was a great physician and medical philosopher until he was afflicted by a case of palsy 1816. He died in 1822.

Further Reading:

• 1815: Dr. Parry shares his wisdom of asthma (5/3/16)

References:

1. Garrison, Fielding Hudson, "An introduction to the history of medicine," 3rd edition, 1821, Philadelphia and London, W.B. Saunders Company
2. Urban, Sylvanus, "Dr. Caleb Hillier Parry," The Gentleman's Magazine and Historical Chronical, from January to June, 1822, volume XCII, London, printed by John Nichols, pages 372-373
3. Roberts, Barbara H., "Treating and Beating Heart Disease: A Consumers Guide to Cardiac Medicines," 2009, Jones and Bartlett Publishers, chapter two: "Treating Angina Pectoris," 
4. Parry, Caleb Hillier, "Elements of Pathology and Therapeutics; being the outlines of a work intended to ascertain the nature, causes, and most efficacious modes of prevention and cure, of the greater number of the diseases incidental to the human frame," Volume I: General Pathology, 1715, London, Printed by Richard Cruttwell
5. Brown, Orville Harry, "Asthma, presenting an exposition of nonpassive expiration theory," 1917, St. Louis, C.V. Mosby Company

RT Cave Facebook Page
RT Cave on Twitter

1800-1900: Eleven asthma theories

The 19th century was an "age of enlightenment" where physicians and scientists started to question old theories of medicine and come up with new ones.  This was an important time in our history, because without it we might probably still be stuck with primitive medicine.

This era was particularly important to the evolution of asthma, as all the theories regarding it, old and new, were hotly debated.  Some physicians were dogmatic, holding on to one particular theory for dear life, while others were more open minded.  Either way, the fact that the disease was openly discussed in the arena of ideas allowed physicians to better understand this disease.

Think of it this way:

• Before 400 B.C. asthma was just another mysterious disease caused by evil spirits or gods.
• In 400 B.C. the Hippocratic writers defined asthma as dyspnea. 
• Around 1700 John Fuller defined asthma as a disease entity of its own, slightly more severe than dyspnea and less severe than orthopnea 
• During the 18th century asthma was basically believed to be a disease in some way associated with and caused by sputum.

During the course of the 19th century there were eleven theories regarding asthma that were hotly debated.  Some were ancient ideas, and some were new.  The most prevalent of these theories are listed here. 

1. Humoral theory of asthma:  This theory postulates that asthma was caused by an imbalance of the four humours: black bile, yellow bile, phlegm and blood. This was the prevailing theory from about 400 B.C. (and probably sooner) when Hippocrates defined it, and the 1st century when Galen reaffirmed it, to the 19th century when scientific theories disproved it. More specifically, Galen believed asthma was caused by an over abundance of phlegm.
2. Dyspnea theoery of asthma:  That asthma and dyspnea are the same thing was established by Hipporates.  Basicallly anything that causes you to be short of breath is asthma; asthma is a symptom, an entity, as opposed to a specific disease. This theory was on the way out the door by the turn of the 19th century, although was pretty much the prevailing thought until the 18th century when scientists and physicians realized there were various causes of dyspnea, and started treating asthma as a disease and not just a symptom.  
3. Symptomatic theory of asthma:  Many physicians believed asthma was nothing more than a symptom of some other malady, such as heart, lung or kidney disease.  Sometimes the cause remained mysterious.  
4. Bronchitic theory of asthma:   Wheezes and dyspnea depend on obstruction of the air tubes by the inflammatory products of bronchitis. This results in excessive mucus production. Dyspnea is less severe and more constant than a paroxysm of asthma. This was the prevailing theory during the 18th century, and it made its way into the 19th century through the writings of Dr. Robert Bree.  A variation of this theory held great sway at the end of the 19th century and was referred to as the Theory of vessel turgescence.  This is basically inflammation of the mucosal membranes that line the respiratory tract, and we might think of it today as bronchitis.  
5. Spasmotic/ convulsive theory of asthma:  Convulsions, Contractions or spasms of the muscles that line the bronchioles are a main component of asthma.  Celsus defined asthma as being caused by "the narrow passage by which the breath escapes, it comes out with a whistle."  The theory was introduced to the medial community by Thomas Willis in 1682, and William Cullen in the next century fine tuned it.  It was a hotly contested theory during the 19th century. 
6. Nervous theory of asthma:  The belief that asthma is nervous in origin, or caused by things that influence the mind -- such as strong emotions like laughter, crying, stress, excessive happiness, excessive sadness, a yearning for the mother, etc -- goes back to the ancient world. Physicians early on observed no organic lesions in asthmatic lungs, and therefore assumed it must be nervous in origin.  They observed asthma was intermittent, sometimes with long intermissions between paroxysms.  This theory the nerves caused spasms in the lungs was introduced to the medical community in the 16th century by Jan Baptiste van Helmont and Thomas Willis, and in the 18th century by William Cullen.  It was proven by the experiments of Francis Ramadge in 1835, Joseph Bergson and Amedee Lefevre win 1836, and Francis Romberg in 1841.  It was given true credibility by the writings of Henry Hyde Salter during the 1850s. 
7. Paralytic theory of asthma:  Asthma is caused by paralysis of the respiratory muscles and this results in dyspnea.  This idea was first established by Dr. Rene Laennec around around 1810 or 1820.  "Bronchial muscles," he said, "are paralyzed and dyspnea is expiratory, more more constant, and less spasmotic."  We might now refer to this as emphysema. (1, page 37)
8. Diaphragmatic spasm theory of asthma:  This theory postulates that tonic spasms of the diaphragm causes asthma.  This theory may have been devised by examining the way asthmatic people breath, and was probably proposed by Thomas Willis and Neumaun (?).  It was also later supported by (M. Alton) Wintrich in the mid 19th century, and later confirmed by Heinrich von Bamberger around 1870.
9. Cardiac theory of asthma:  This is the theory that asthma is caused by blood being sucked into the lungs causing congestion and dyspnea. During the 19th and early 20th centuries it was often referred to as a type of asthma.
10. Reflex theory of asthma:  This theory postulated that something other than the lungs causes it.  Eating too much or eating certain foods can effect a nerve and send a "reflex" signal to the lungs, which responds by causing the airways to contract.  For example, catarrh or inflammation of the nose can cause spasm of the muscles of the lungs by reflex action.  Most who support this theory believed some form of disturbance in the blood was the result.  Other causes of this might be a response from the urea, disturbance of metabolism, dyspepsia, etc. However, some who support this theory believed it was just an extehnsion of the nervous theory of asthma.
11. Hay fever theory of asthma:  Hay fever leads to asthma.  Some speculate inflammation (or catarrh) of the upper airway leads to inflammation of the lower airways of the lungs, leading to bronchitis or asthma. This is a theory that has recently gained momentum.
12. Other:  Yes, lots of other theories existed.  Some doctors just let their imaginations fly free. Dr. Breuer, for example, "believed there was an automatic control of breathing through the vagi and that the stretching of the alveolar walls stimulates expiration and hinders inspiration. An increasing of the total lung volume," he said, "would tend to stimulate expiration rather than inspiration." (1, page 37) Some theories may have been scientifically justified, and others, such as Breuer's, mere speculation. Other physicians noticed asthma improved after removal of polyps in the respiratory tract and sinuses.

Of all the theories regarding asthma during this era, Orville Brown said in 1917 in 1917:

The multitude of theories some ingenious and helpful and others far fetched and convincing evidence of a fruitless search, have failed to receive much attention."  (1, page 25)

For the most part, each physician had a favorite theory, found evidence to support it, and adjusted the definition slightly as evidence indicated.

So, what theory won the era? 

References:

1. Brown, Orville Harry, "Asthma, presenting an exposition of nonpassive expiration theory," 1917, St. Louis, C.V. Mosby Company.  The above mentioned theory of vessel turgescence comes from this reference also on page 25. 

RT Cave Facebook Page
RT Cave on Twitter

1790: Defending old asthma theories

Dr. Robert Bree (1790-1859), an English physician who had asthma, wrote a book about asthma in 1797 called "A Practical Inquiry into Disordered Respiration, distinguishing the Species of Convulsive Asthma, their Causes, and Indications of Cure." It would go on to become the most read asthma book of the first half of the 19th century.

Dr. Bree was an ardent proponent of the bronchitic theory of asthma, a theory that states asthma is caused by an increase of phlegm in the lungs. The theory is similar to those postulated by ancient physicians, such as Hippocrates and Galen.  In this way, he is one of the last known physicians to defend old asthma theories.

He believed that the treatment of asthma was relative to the cause. He said asthma was caused by inhaling a peccant matter, and was cured when the peccant matter was expectorated.  This explained why asthma always ended after a fit of coughing that produced a wad of phlegm.

In this way, he believed modern theories regarding diseases like asthma were often the subject of quackery.  By autopsies and experiments he performed, he attempted to prove men like William Cullen, who postulated that science was a wiser approach to medicine than ancient theories. He was also one of the first physicians to describe asthma as spasmotic and nervous. (3)

Proving Cullen wrong about asthma was the essence of Bree's 1797 book.  He said Cullen is wrong because no science proves the nervous or spasmotic theory of asthma, especially considering those two conditions cannot be seen on autopsy.

On the other hand, phlegm can be seen on autopsy. So, if anything, science supports the bronchitic theory of asthma and the theories of the ancients, more so than the ideas of Cullen.

However, Bree did not completely reject the spaspotic theory of asthma, he simply considered it as secondary to some other cause.  In reviewing the opinions of Dr. Bree in 1890, Ernest Schmiegelow said:

Bree does not actually deny the possibility of bronchial spasms taking some part in the cause of asthma, but it is only secondary; the primary cause is an exudation in the bronchial tubes, by which the lungs (specially the muscles of respiration) are stimulated to contraction, in order to expel the mucus which they contain. (4, pages 8-9)

In other words, Bree believed mucus was the cause of most diseases, including asthma.  He believed the contraction of the lungs was a defense mechanism to expel mucus from the lungs.

About 30 years after Bree published his book the stethoscope was invented, and as soon as it was used to listen to asthmatic lungs Dr. Bree's theory was disproved, said Schmiegelow.  He said that once the stethoscope gained favor, it was easy to prove that an attack of bronchitis does not precede an attack of asthma, and that rhales (a lung sound Laennec used to describe the sound of secretions in the lungs) are heard later during the attack.

While Bree waswell respected in his day, his ideas about asthma, and even most of his remedies, slowly gave way to science.  In this way, Despite Bree's noble efforts, his bronchitic theory of asthma eventually took a back seat to Cullen's nervous and spasmotic theories.

Regardless, all three theories would be debated over the course of the 19th century.

Continue the journey by clicking here.

References:

1. Pepper, William,  Louis Star, "A System of Practical Medicine," Volume 3, page 184
2. Berkart, J.B., "On Asthma: It's pathology and treatment," 1878, London,  Chapter II, "History of Asthma," page 12
3. Bree, Robert, "A Practical Inquiry into Disordered Respiration, distinguishing the Species of Convulsive Asthma, their Causes, and Indications of Cure, London, 1810.  I could not find the 1790 edition online, yet this one serves our purpose.
4. Schmiegelow, Ernest, "Asthma, considered specially in relation to nasal disease," 1890, London, page 4 
5. Jackson, Mark, "Asthma: The biography," 2009, London, pages 86-88 (If you're interested in a good asthma history book, this is it.)

RT Cave Facebook Page
RT Cave on Twitter