1874: Solis Cohen recommends tracheotomies for croup

While physicians of the 18th and 19th century were frequently afraid to perform the procedure of tracheotomy, a few physicians, such as Dr. Armand Trousseau, Dr. J. Soles Cohen, and Dr. Morrel Mackenzie strongly recommended that every physicians become adept at the practice, as it is sometimes the only means of saving the life of a child who is suffocating daue to croup.

Mackenzie, a nose and throat specialist , said the first person to recommend the operation of tracheotomy for croup was Francis Home, who published a book on the subject in 1765 called "An Inquiry into the nature, cause and cure of croup." (1, pages 134, 523)

He said various other physicians followed suit, including doctors Crawford, Chaussier, Schwilgue, and others.  (1, page 523)

Trousseau (1801-1867) was an ardent supporter of the procedure, and his thoughts on the subject were often referenced by Cohen as he attempted, in his 1874 book "Croup, in its relations to tracheotomy," to convince his colleagues the procedure was sometimes necessary, and that every physician should become adept in performing the operation.

The procedure had been performed many times in the ancient world, although with great difficulty and risk.  Cohen said it wasn't until 1782 that the first successful tracheotomy for croup was performed, and this way by John Landree in London, and later by Chevalier in London in 1814.  (2, page 7-8)

He said Bretonneau also performed a successful tracheotomy for croup in 1825, yet that was only after two unsuccessful attempts in 1818 and 1820. Professor Stolz succeeded in 1825, and Armand Trousseau in 1833. (2, page 7-8)

Trousseau, Cohen said, "remained the most zealous advocate of the operation during his entire life." (2, page 7-8)

Cohen also explained that successful tracheotomies were rare prior to the 1850s, and the main reason for a rise in success rates was improved care during the procedure, which was mainly due to a new idea called the germ theory of disease.
Post operative deaths declined slightly due to increased attention paid to these patients following the operation.  (2, page 8)

Cohen went on to note statistics comprised by various studies performed that resulted in increased confidence in performing the procedure. (2, pages 8-26)

It should be noted, however, that during this time in our history it was rare for a patient to visit a physician in a controlled setting.  In most instances, when a person was sick, a physician was sent for, and he rode in on his horse and buggy to take care of his patient.

So it was very rare for the operation of tracheotomy, or any operation for that matter, to take place in a controlled setting.  If efforts to control infection were made, it was solely the responsibility of the physician.  One could imagine that, upon observing a young child who was suffocating due to a swollen throat, that a physician would have little time to consider aseptic procedure.

Despite this fact, Cohen said a patient would be more likely to survive such an operation at home than in a hospital.  Cohen said that...

...hospital cases in themselves, as a rule, offer less chance of recovery than cases in private practice, though the operation is frequently performed better, and the after-treatment is much more assiduous." (2, page 8)

A common cause of distress among children, and a common cause for the airway to become swollen and cause suffocation, was croup.  By this age there was a lot known about this disease, particularly that it was inflammation of the throat that can occur as a result of diseases like diptheria.  (2, page 27)

Cohen recommended, that upon visualizing a child, or adult, with croup, that an immediate assessment be made, and the decision to perform a tracheotomy should only be made "whenever it is apparent that death from suffocation cannot be averted by any other means."  (2, page 27)

In other words: tracheotomy should only be used as a last resort to save a life.

The procedure involved the physicians cutting the throat with a blade.  It would have been distressing for all involved, and very painful for the child.  It would have required the parents, and anyone else in the room, holding the child still. It would not have been a pretty site to behold.

When the child was screaming, writhing and turning during the procedure, this increased the risk that the physician would make an incision in the wrong spot. This could cause extreme agony, although it could also increase the risk of death.

For this reason, when the procedure was performed in Great Britain, Germany and the United States, chloroform was would be used as an anaesthetic.  The physician would be well versed in how to obtain it, how to store it, and how to provide it to a patient.  In the case of a screaming child, he would use it liberally, although never in an amount that would risk the child dying as a result of the poison.  (2, page 34)

If you lived in France, however, and you were the poor child suffering, your physician would not provide you with an anaesthetic.  Surely the drug was good for calming a child down, but if given in too high amounts this would cause breathing to become so shallow that asphyxia sometimes occurred, resulting in brain injuries and death.  (2, page 34)

This was especially a concern because there were no standard doses, and it was particularly difficult for a physician to accurately dose a small child.  When not enough was given, the child would continue to fight.  However, when too much was given, the risks were too severe for French physicians to recommend the poison.  (2, page 34)

Regardless of the option to use Chloroform, many physicians were slow to use it, and slow to perform the procedure of tracheotomy, because there was always the hope that other methods would work.  The dilemma of where to draw the line, and when to perform the procedure, continued to plague physicians.  Cohen said: (2, page 5)

Tracheotomy for croup is generally regarded with much disfavor in this city. Its results in Philadelphia have been less encouraging than almost anywhere else; probably because, as a rule, the operation is postponed too long; possibly because our medicinal treatment of croup cures a number of cases which, under less efficient management, would become subjects for tracheotomy; but, whatever the cause, the results, in the comparatively few instances in which the operation has been performed, have been so disheartening, that many practitioners refuse to sanction tracheotomy in croup under any circumstances. This radical feeling is wrong. Not only should our individual experience be utilized in judgment, but the recorded experience of others also. Early failures may be followed by ultimate successes. (2, page 5)

To encourage physicians to use the procedure when needed, he provided statistics. He said: :

Barthez, in a letter to Eilliet on the comparative results of the treatment of croup by tracheotomy and by medication during the years 1854-1858, stated that the first year the Hospital Sainte-Eugenie was opened, 13 croup patients were submitted to tracheotomy, of whom the first died during the operation, and 11 others in succession after the operation; the first recovery taking place in the thirteenth case. Yet Barthez had many successes afterwards; for in a letter published in 1868, he stated that in the same hospital, between the years 1861-1867, 785 cases were operated upon, with 222 recoveries. Guersant lost his first 23 cases, between 1834-1841 ; but after that saved 17 out of 82.

He also referred to statistics by  Armand Trousseau, a 19th century physician who strongly recommended the procedure.  Cohen said:

Trousseau, up to 1842, had operated 119 times, with but 25 recoveries; but at a later date (1854) he reported 222 operations with 127 recoveries. Similar examples of early want of success followed by results truly gratifying are on record. But there have been results even worse than these. Thus Trousseau, in a discussion on tracheotomy in croup, before the Academy of Medicine, in 1858, mentioned, that in the earlier days of the operation, Gosselin, Deguise, Huguier, Jarjavay, and Monod, Jr., of Paris, performed 95 operations successively without a single recovery; that Alphonse Guerin, Mtchon, Laugier, Robert, Nelaton, Lenoir, and Depaul saved but 11 cases out of 117 operations; and Velpeau, Jobert, and Desormeaux but 16 out of 84. He attributed much of this want of success to the idea then prevalent that the surgeon's duty ended when he had opened the trachea. (2, page 5-6)

Trousseau, therefore, recommended that the physician should continue to care for the patient long after the operation was performed.  If he was unable to attend the patient after the operation, it was his job to educate those would were, particularly parents, spouses, relatives, or friends who would be taking care of the patient.

Despite the risks, despite the fears of the physician, despite the anger of parents who watched as their children had their throats cut open, Trousseau recommended that the physician should not be afraid to use the procedure to save a life, and lack of skill and fear was no excuse to evade the procedure.

He strongly recommended that every physician become educated about the proper methods of performing the procedure, and to then to perform it whenever a need arose.  Since practice makes perfect, he suggested that the more a physician performed the procedure the better he would become capable of performing it. The statistics he offered in his book were used to prove it.

Cohen said:

That tracheotomy saves many croup-patients from death otherwise inevitable, and that, too, even under unfavorable circumstances, there has long been no reason to doubt: there is little doubt, either, that patients are occasionally tracheotomized unnecessarily; but the proportionately small number of such instances, whether errors of judgment or errors of prudence, is, in all probability, insignificant in comparison with the number of patients saved by the operation from certain death; life being preserved in the one instance, while it is not sacrificed in the other. (2, page 6)

Cohen reminds physicians that tracheotomy is not a cure for croup, and that it is merely a means of postponing death to allow nature, along with the physicians remedies, time to work.  He said:

Tracheotomy, in itself, does not cure croup. It affords a possibility of recovery by postponing, or insures it by averting death. The course of the disease is continued until all its attendant phenomena have undergone evolution. The surgeon's knife merely cuts a path for air to reach the bronchi in quantity sufficient for the requirements of the respiratory process, and saves the muscular force, exhausted in futile efforts at respiration through the glottis. Is it not possible that the freedom of breathing, and consequent conservation of strength, would aid the system to resist the full effects of the development of the disease, in the further production of exudation, or its plastic deposition upon the bronchial mucous membrane? Then the artificial opening affords a better means of escape for the false membrane, whether dispelled by cough or removed by instruments inserted through the wound; it enables a more efficient application of local remedies to retard the congelation of the exudation into membranes or casts; and thus facilitates the discharge of the plastic material by cough. In short, it gives the patient a chance, offered by no other means, to live and fight through the development and decline of the disease. (2, page 6-7)

A cannula was usually inserted into the stoma, and usually the one's used were double lumen. A double lumen was first used by George Martin in 1730, and was modified by Trousseau.  Cohen said it was important to insert the cannula...

...so that the inner tube projects a little beyond the terminal extremity of the outer one, so as to free the latter when the former is removed or inserted. The proximal (the part closest to the patient) extremity of the outer tube should be suspended by movable joints in a perforated plate to be fastened upon the neck by means of tapes or to adjust itself to the movements of the trachea, avoids pressure against the mucous membrane to some extent; and, thus far, prevents ulceration of the trachea; a serious complication which sometimes attends a prolonged use of the tube, though it sometimes occurs within 36 or 48 hours. The size of the tube should be as large as can be conveniently employed without touching the walls of the trachea. Trousseau thinks that the canula should be of larger calibre than the glottis. Others recommend that it should be about as large as the calibre of the cricoid cartilage, which is considerably less than that of the trachea, in some cases much less. By having a number of tubes of graduated sizes the nicety of adjustment may be attained, whatever may be the age of the child; the same sized tube employed promiscuously for all cases, as is the habit, will not always be well adapted to the case in hand. Too short a canula may be coughed outside the trachea, rendering the patient liable to become asphyxiated in a few moments by its pressure externally. Three times an accident of this kind occurred in Trousseau's practice (2, page 48)

According to Mackenzie, Soles-Cohen was among the many physicians of this era who worked to...

...modify the instruments, to improve the method of procedure, to determine the relative merits of the various operations on the air passages, or to lay down more clearly the indications for the performance of these operations." (1, page 523)

So by trial and error, various improvements were made to both the technique used in performing the operation of tracheotomy and in caring for the tracheostomy after the procedure.  The cannula and inner cannula were improved so that by the end of the 19th century the models used were recognizable to those used today.

A few more advancements would be made during the next several decades, and, finally, in the 1940s the procedure would be perfected.

References:

1. Mackenzie, Morrell, "Diseases of the athroat and nose, Volume I, 1880, Philadelphia, Presley Blakiston
2. Cohen, J. Solis, "Croup, in its relation to tracheotomy," 1874, Philadelphia, Lindsay and Blakiston

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1500-1900: Physicians experiment with protecting the airway

Antonio Brasavola (1500-1555)

Every once in a while I have to have a post that lists a bunch of information all at once, and this is one of those posts. Basically, I just want to give a brief synopsis of the evolution of tracheotomies and intubation -- two methods of creating an artificial airway -- from the Renaissance to the turn of the 20th century.

Tracheal openings, creating an airway by making an incision in the throat, were used in the ancient world by physicians who wanted to keep animals alive while doing experiments on them.  (1, page 269-280)  

So over time certain physicians became quite adept at creating them, which probably came in handy the few times they were needed for upper airway obstruction (probably due to some disease that caused inflammation in the throat, like diptheria).

Aound 400 B.C., Hippocrates described preventing asphyxiation by inserting a tube into the airway. He wrote in "Treatise on Air," that "One should introduce a cannula into the trachea along the jawbone so that air can be drawn into the lungs." While it was probably used before earlier, this is the first known description of endotracheal intubation. (

Andreas Vesalius, (1514-1564)  the same person who proved that Galen wasn't a know all about medicine, described in his 1543 book, De humani corporis fabrica ("On the Fabric of the Human Body"), how he could provide breaths to animals by blowing into a reed inserted into their necks through a tracheal opening. (2, page 67)(x3, page 5-7)  

In 1546 Antonio Brasavola of Italy performed a tracheostomy on a patient with tonsilar obstruction, and through Vesalius, Brasavola and other physicians during the Renaissance  reintroduced the world to tracheotomies and there ability to save lives. (9, page 224)

In 1667 Robert Hooke (1635-1703) took the trachea of a dog and connected it to a "pair of bellows, and the ribs and diaphragm were removed; the dog was seized with convulsions and appeared to be dying, but revived when air was blown into the lungs. Small punctures were then made into various parts of the lungs, and by means of two pairs of bellows the lungs were kept fully distended with fresh air; the dog remained quiet and its heart beat regularly. The circulation continued although there was no alternate expansion and collapse of the lungs; moreover, a further experiment showed that even when the lungs were allowed to collapse the blood continued to circulate for some time." (4, page 474)

By his experiment, Hooke also proved that "by blowing a bellows briskly over the open thorax of a dog, that artificial respiration can keep the animal alive without any movements of either chest or lungs." (5, page 267)

In 1714 Dethharding recommended using mouth to mouth breathing to resuscitate near drowning and other such victims.   In 1732 a Scottish surgeon named Dr. William Tossack successfully used mouth to mouth breathing to revive a coal minor who stopped breathing due to suffocation, and as a result rescue breathing became common by the 1840s. (1, page 269-280)

However, once the germ theory was established this was deemed as harmful to the rescuer and bellows were used.  Many suspected this too was harmful to victims because it might blow out a lung, so physicians refused to do it.  (6)

While a cannula through the stoma created by the tracheotomy was used to maintain the airway for quite a few years already, George Martin was the first to use a double cannula in 1730 "on the suggestion of one of his friends." (11, page 48.

"This valuable suggestion was, however, soon forgotten" by the medical community in general.  (10, page 522)

In 1754 Benjamin Pugh of England inserted an "air pipe" into newborn infants who were not breathing, and soon thereafter intubation became common for near drowning victims.  Aware of the benefits of creating an airway, a physician by the name of Curry developed an "intralaryngeal cannulae" to use for resuscitation efforts.  (7) 

In 1783 De Poiteau recommended the use of tracheas when administering positive pressure breaths to drowning victims in order to let water out and warm air in and out by using a tube.  Tracheotomy tubes were further refined as the century came to a close.  Use of tracheotomies ultimately waned in favor of intubation (placing a tube or cannula into the airway to the trachea). (2, page 67-72)  

Lorenz Heister (1683-1758)

As noted earlier, Lorenz Heister (1683-1758) was the first to refer to the procedure as tracheotomy, as prior to this it was simply referred to as bronchotomy. (10, page 520)

Overall, most accounts of the procedure of tracheotostomy mention physicians "look upon it with great distrust" until the 18th century when Antoine Louis published articles on 'bronchotomy'  (8, page 198-199)

By the 1830s there were enough positive experiences with tracheotomies, by others and himself, that resulted in Armand Trousseau (1801-1867) becoming an ardent proponent of the procedure, recommending it to his colleagues. (10, page 523)

Because of his "unabound enthusiasm... his immense industry, and careful attention to detail, not only before, but during and after the operation, (he) soon established the position of tracheotomy in modern surgery." (10, page 523)

Trousseau is now considered the father of tracheotomy. (12)

Despite Trousseau's improvements of the tracheotomy technique, and the fact more physicians were willing to perform the procedure for croup caused by diphtheria, the inflammation was so severe in many such patients, especially small children, that other methods of creating an airway were experimented with. This lead to the first attempts at creating an airway by using a tube inserted from the mouth or nose into the lungs. (12)

Attempts were made to catheterize the larynx in 1839 by Dieffenbach of Berlin, and in 1855 by Reybard in Lyon and Weinlechner in Vienna, although none succeeded. (12)

Eugene Bouchut (1818-1891)

In 1858 Eugene Bouchut succeeded in two of seven cases, yet his tube was made of wood and caused so much trauma to the patient, that the entire idea was criticized as "harmful and traumatic" by the well respected Trousseau, who said the operation of tracheotomy, despite its low success rate, was much more tolerable. (12)

Discouraged when his idea was rejected, Bouchut set aside his attempts at finding a better method of creating an airway in favor of research in other areas.  (12)

Joseph P. O'Dwyer (1841-1898)

The idea was not taken up again until 1885, when Joseph P. O'Dwyer, himself a pediatrician, picked up where Bouchut left off, and made a few small adjustments to make the procedure more comfortable for the patient. (12)

Still, for the time being, the tracheotomy was the main method of creating an airway for patients who were in an imminent threat to suffocating due to inflammation of the throat, regardless of the cause. Although, for those who wanted to risk it, there was a viable endotracheal tube.

In 1858 Roget came up with the idea of connecting the "tube to it's shield by means of a collar permitting movement between the two parts." (10, page 523)

Since then various other improvements to the tracheostomy have been made by various physicains, including Sales-Cohen, who also invented an early inhaler/ nebulizer.

Through most of history tracheotomies were mostly performed when the patient was suffocating due to severe airway obstruction.  During the 18th century the procedure was still recommended for foreign body obstruction of the larynx (i.e., choking due to large chunk of steak stuck in throat), although physicians started experimenting with the procedure for specific disease processes or symptoms, such as inflammation of throat tissue, severe inflammation of the tongue, mumps, diphtheria, near drowning, drowning, large nasal and pharyngeal polypi, severely swollen tonsils, and croup.   (10, page 522-523)

However, despite all the experiments and recommendations made during the 18th century, it wouldn't be until the 19th century that tracheotomy and intubation would be recommended and practiced with regularity. (8, page 198-199)

References:

1. Lee, W.L., A.S. Stutsky, "Ventilator-induced lung injury and recommendations for mechanical ventilation of patients with ARDS," Semin. Respit. Critical Care Medicine, 2001, June, 22, 3, pages 269-280
2. Price, J.L., "The Evolution of Breathing Machines," Medical History, 1962, January, 6(1), pages 67-72; Price references The Bible, Kings, 4: 34 
3. Tan, S.Y, et al, "Medicine in Stamps:  Paracelsus (1493-1541): The man who dared," Singapore Medical Journal,  2003, vol. 44 (1), pages 5-7
4. Hill, Leonard, Benjamin Moore, Arthur Phillip Beddard, John James Rickard, etc., editors, "Recent Advances in Physiology and bio-chemistry," 1908, London, Edward Arnold
5. Garrison, Fielding Hudson, "An introduction to the history of medicine," 1922, Philadelphia, W.B. Saunders Company
6. "Resuscitation and Artificial Respiration," freewebs.com, Scientific Anti-Vivisectionism,  http://www.freewebs.com/scientific_anti_vivisectionism4/resuscitation.htm, accessed March 1, 2012 (see also reference 1 above)
7. Ball, James B, "Intubation of the Larynx," 1891, London, H.K. Lewis
8. Fourgeaud, V.J, "Medicine Among the Arabs," (Historical Sketches), Pacific medical and surgical journal, Vol. VII, ed. V.J. Fourgeaud and J.F. Morse, 1864, San Fransisco, Thompson & Company,  pages 193-203  (referenced to page 198-9)
9. Szmuk, Peter, eet al, "A brief history of tracheostomy and tracheal intubation, from the Bronze Age to the Space Age," Intensive Care Medicine, 2008, 34, pages 222-228
10. Mackenzie, Morrell, "Diseases of the athroat and nose, Volume I, 1880, Philadelphia, Presley Blakiston
11. Cohen, J. Solis, "Croup, in its relation to tracheotomy," 1874, Philadelphia, Lindsay and Blakiston
12. Sperati, G., Felisati, D., "Bouchut, O'Dwyer and laryngeal intubation in patients with croup," Acta Otorhinolaryngol Ital, 2007, 27 (6), 320-323

Further reading: 

click here and here 

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1-1619: Jews, Arabs and Latins practice tracheotomies (and mouth to mouth breathing)

Chances are early tracheotomies were performed with no anaesthetics.  I write this not that I know this for sure, although I would imagine the procedure was generally performed as a last ditch effort to try to save a life of a person who was otherwise suffocating and was probably going to die if nothing was done.

There were, however, medicines that could have taken the edge off, such as opium.  Opium is an opiate that is one of the oldest known medicines known to man.  It is described in some of the earliest writings shared among the medical community.  So if the opportunity presented itself, this or some other medicine could have been taken to ease pain and suffering.

The ancient Jews, after the birth of Christ (around the years 1-650 A.D.) were known to perform surgeries when prayer, magic and natural remedies did not work.  When they did resort to surgeries, they did have certain herbs that were perhaps mixed into a drink that was used as a sleeping draught. (1, page 62)

The Jews were nomads, which means they traveled to many places in search of a home.  They spent time among the ancient Mesopotamians and Egyptians, and in the process they picked up a lot of knowledge about medicine.  Perhaps among the medical procedures they learned about from either of these places was the operation later to be called tracheotomy by the Greeks.  As they traveled they may also have educated other civilizations of the procedure.  This was one of the ways medical knowledge traveled through time.

Renouard explains that "the Arabs, and the Latins of the Middle Ages, had so little anatomical knowledge that they very much exaggerated the dangers of the operation, and, without condemning it absolutely in theory, abstained from its practice." (2, page 449)

Although this was not always the case.

Paulus Aegineta (625-690), as was noted earlier, performed the procedure with regularity, and described the procedure pretty much as Antyllus had several hundred years earlier.  (5, page 521) The operation was not regularly practiced until the 16th century, yet most of what was written was a reproduction of what Antyllus wrote on the subject.

Rhazes (865-925), Mesue (777-857), and Avicenna (980-1037) do not mention the methods of the procedure, but recommend it as a last option in cases of "angina strangulans." (3, page 199)  Avecenna did, however, describe "intubating the trachea using 'a cannula of gold or silver.'" (4pages 222-228) 

In the 12th century Arabian physicians Avenzoar and Albacasis were among the few physicians who dared to perform tracheotomies, although prior to them the procedure was rarely performed. Avenzoar (Ibn Zuhr), who was the most renowned physician and surgeon after Avicenna,  noted experiments of the procedure on goats, although he recommended it not be done unless the physician had knowledge of anatomy.  (3, page 198)  (6, pages 70-71)

Of course anatomical knowledge was rarely obtained by physicians mainly because autopsies were rarely performed, and when they were it must have been an unwholesome event.  Historian Fielding Hudson Garrison, in his 1922 history of medicine, explains that bodies were probably stolen, and both the grave robber and the autopsy performer would have risked an untimely death if caught.  There were a few books describing anatomy, although chances were good the descriptions were from animal dissections: pigs, dogs, apes, etc. (1, page 415)

The Surgeon Lanfranchi of Milan (1250-1306), Garrison explains,  was a surgeon at the School of Salerno in Northern Italy who may have been the first physician to mention intubation.  He became involved in the "squabbles of Guelphs and Ghibellines and was exiled.  He arrived in Paris in 1295, where he introduced the French to Italian medicine.  So it's highly likely the French also had knowledge to the technique of intubation.  (1, page 144)

Renouard continues:  "Anthony Benivieni, a physician of Florence, who lived at the end of the fifteenth century, saved the life of a patient by opening the trachea, and giving issue to the pus of an abscess that was formed within it. This is the first account we have of a tracheotomy, after an interruption of twelve hundred years; but its author does not state the manner in which he performed it, and it does not appear that he employed this method in other cases." (2, page 449)

Along with tracheostomies, mouth to mouth breathing also is mentioned in the fifteenth century.  It was documented to have been performed in Italy to revive newborn infants stunned at birth and not breathing on their own. This would have been a major effort on the part of the caregivers to save the life of a newborn infant stunned at birth who otherwise would have had no chance at life.  (5 need reference)

Fabricius d’Aquapendente (1537-1619), Renouard said, "is the first among moderns who gives a detailed description of this operation. He proves that it may be executed without injury to any other important organ; and that by it, we may often save a patient from impending death. The invention of the canula has been attributed to him, which has usually been left for some time in the artificial opening thus made. (2, pages 448-449)

In 1596 Sanatorius became the first to use a trocar to insert a cannula into the stoma, "and left a canula in the opening for three days."  Fabricius ab Aquapendente, in order to prevent the cannula from falling into the airway, added a cannula with wings.  Later later his pupil, Casserius, "made a very important improvement in introducing a canula with a curve corresponding to the arc of the quadrant, and he also tied in position the canula with tape.  The improvement in the shape of the instrument, however, was soon lost sight of, and the straight tube long remained in use." (5, page 521)

So knowledge of how to create an airway made it's way through the dark ages of medicine in the west, and the bright ages of medicine in the east.  Now it would make it's way to the Renaissance, where improved anatomical wisdom would help speed up the advancement of medical wisdom.

Note:  Spelling within quotes is that of the original author

References:

1. Garrison, Fielding Hudson, "An introduction to the history of medicine," 1922, Philadelphia, W.B. Saunders Company
2. Renouard, Pierre-Vincent, "History of medicine: from its origin to the nineteenth century,"
3. Fourgeaud, V.J, "Medicine Among the Arabs," (Historical Sketches), Pacific medical and surgical journal, Vol. VII, ed. V.J. Fourgeaud and J.F. Morse, 1864, San Fransisco, Thompson & Company,  pages 193-203  (referenced to page 198-9)
4. Szmuk, Peter, eet al, "A brief history of tracheostomy and tracheal intubation, from the Bronze Age to the Space Age," Intensive Care Medicine, 2008, 34, pages 222-228
5. Mackenzie, Morrell, "Diseases of the throat and nose, Volume I, 1880, Philadelphia, Presley Blakiston
6. Bradford, Thomas Lindsley, writer, Robert Ray Roth, editor, “Quiz questions on the history of medicine from the lectures of Thomas Lindley Bradford M.D.,” 1898, Philadelphia, Hohn Joseph McVey