|How procedure was performed circa 1891 (23, page 20)|
Such inventions were crude back then, and the methods of performing them must have been traumatic for the patients receiving them, yet they gave physicians something to work with in order to help their patients. The more these physicians struggled, the better they got. The more they tinkered, the better their equipment got.
Here is a pithy progression of some of the results that transpired due to the hard work, and crafty thinking, of a few admirable physicians.
1500: A paralytic discovered for modern world: Curare (Succicholine) was one of the most famous native American poison, as the Indians often placed it on the tips of their arrows in order to paralyze their prey. (18, page 4, 177-178) Sir Walter Raleigh first reported the paralytic when he discovered that the South American Tupi Indians used the poison on the tips of their hunting darts. (19, page 1674)
1773: First resuscitation of near drowning victim: According to a 1920 publication by the Lungmotor Company, "Drowning: Historical-Statistical Methods of Resuscitation," "The first reliable history of a resuscitation from drowning was that performed by M. Reamer in Switzerland. This was reported to the French Academy of Sciences and translated into English by Dr. Crogan in 1773. About this time Dr. Fothergill published his "Physical Dissertation on Drowning," which was read before the Royal Society in England. In 1773, the first society for the rescue of those apparently drowned was instituted at Amsterdam, Holland." (20, page 3) (22, page 1)
1774: Humane Society uses bellows to help drowning victims: Members of the society recommended the use of bellows to breathe for victims of accidents (mainly drownings). They recommended that the end of the bellows be placed in one nostril, while the other nostril and mouth were occluded by a second operator. One problem that often occurred was air entering the stomach. A second problem was the tongue blocking the airway. Goodwin ultimately recommended a catheter be inserted into the other nostril into the esophagus to prevent air from getting into the stomach and to keep the tongue from blocking the airway. (22, page 2) (18, page 50-52)
1788: Endotracheal tube: The first endotracheal tube was invented in 1788 by Charles Kite (Kyte). He was a surgeon who wrote an essay titled, "The Recovery of the Apparently Dead," in which he described inserting a tube he referred to as a catheter through one of the nares or the mouth to the lungs whereby the operator could either provide positive pressure breaths either by placing his mouth over a mouthpiece or by using bellows. To cause expiration Kite recommended pushing in on the abdomen. Various bellow-type systems were available for providing positive pressure breaths. He also recommended a catheter that was inserted into the esophagus to prevent the tongue from blocking the airway. On the catheter as a ivory sliding piece that was slid down with a finger into the gullet in order to block the esophagus and prevent air from entering the stomach. Kite's equipment was included in the Case of Resuscitating Instruments that was kept at the various Receiving Houses (Rescue Stations)(1)(23, page 50-52)
1826: Bellows fall out of favor: Experiments in 1826 Leroy d'Etiolles performed studies using bellows and noted in a report that "bellows could kill an animal by suddenly inflating the lungs." (23, page 2) This was among the first reports that showed that over inflating the lungs with too much positive pressure could cause the lungs to collapse. Due to this report, bellows were no longer recommended by the Humane Society. (23, page 2) However, in 1888, "experiments by Leroy were performed that proved that a collapsed lung only occurred when the pressure forced into the lungs was too high, such as greater than 20-80 mm of mercury in the lungs of infants. As a result of his experiments, he "invented a safety bellows to obviate these effects. The bellows had a scale graduated in ages attached to the handles to limit the volume of air delivered." (1) Experimenters in the succeeding years attempted to create a system of bellows, or methods o fusing them, that were safer to the patient.
1793: Intubation to treat diseased patients: Prior to this time artificial respiration was generally used to treat near drowning patients or for some other purpose. Yet near the end of the 18th century artificial respiration was thought to benefit people with diseases or conditions that result in dyspnea or asphyxia. This was a time when a tube was sought to be kept inside the airway long-term as opposed to temporary. Xavier Bichat, a pupil of French surgeon Desault, describes how Desault decided to insert a catheter into the larynx of a patient in impending respiratory failure as opposed to a tracheotomy. Desault is considered the first to apply artificial respiration for dyspnea. In many cases the patient's breathing became easier, and in one case the patient's breathing became easier and was extubated 24 hours later. Desaults cather "was a large gum-sized elastic catheter, with two large eyes and an opening inferiorly, adn he introduced it through one of the nasal fossa rather than the mouth." Catheterization became a common procedure in France, although later fell into disuse. (3, page 2-4)
1800?: A paralytic discovered for modern world: Curare was one of the most famous native American poison, as the Indians often placed it on the tips of their arrows in order to paralyze their prey. American physicians discovered this poison early on in the 19th century (exact date unknown). Physicians tried to find a safe dose for using it as a paralytic, which was hard to do. They also experimented with various diseases to see if it had beneficial effects. The poison would become an important medicine used by physicians, although it would be a few years before it was proved useful as an anesthetic. (18, page 4, 177-178)
1807: Method of making Curare discovered: After Curare was mentioned by Sir Walter Raleigh, many people believed it was made from "poison dart frogs." Alexander von Humboldt discovered that this was not true, that the poison was derived from various vines in the rain forest. The stems, roots and leaves were crushed and boiled into a paste, which was sometimes mixed with frog and snake venom. A thick black paste was placed on the tips of darts. As they pierced through the skin, the poison would enter the blood stream causing the animal to become paralyzed. Breathing would cease, and the animal was turned into easy prey. This would be a major breakthrough for modern medicine, because it would allow physicians an opportunity to experiment with it on animals, and ultimately on patients of various types. (19, page 1674)
1814: First use of experiments with muscle relaxants: Benjamin Brodie (1783-1862) and was an English surgeon who performed experiments using Curare (Succicholine) on a donkey, and he proved that so long as the animal was provided with artificial breaths, it could be kept alive during an operation. (2, page 227)(17, page 25) Charles Waterton gave the Curare while "Brodie supplied the experimental idea." Bellows were used to breathe for the animal for two hours. The animal lived another 25 years. (17, page 25)
1839: Intubation fails Dieffenbach of Berlin tried to catheterize the larynx of a patient inflicted with croup caused by diphtheria and failed. (8)
|Figure 1(23, page 6)|
1837: Artificial breathing condemned: In 1837 Leroy d'Etoille was concerned about the use of such artificial breathing because he suspected it caused emphysema and would collapse the lungs (pneumothorax). This simply provided another excuse not to perform the procedure, because after the germ theory was established in the late 19th century all methods of performing artificial breaths (positive pressure breathing) was banned for the next 100 years before it's value would be re-established in the later half of the 19th century. (7)
1845: Oxygen breaths: A man named Erichson invented the first device that provided positive pressure breaths with oxygen through a cannula inserted through a pipe inserted into one of the nostrils. He recommended ten breaths a minute.
1850: Jaw-Thrust technique recommended: One of the problems that must have ensued when a patient was anaesthetised during surgery was asphyxia (or increased risk of it) due to upper airway obstruction. To resolve this problem, anaesthesiologist Joseph Clover (1825-1882) performed the "jaw thrust- chin life" procedure." The physician used chloroform as an anesthetic in over 7,000 operations without a single fatality, so other physicians must have been eager to copy his successful techniques. Due to side effects, and the death of a little girl as a result, the use of chloroform started to wane by 1864, and by WWI was essentially replaced with better, safer anaesthetics (which included both explosive gases and injection through the hypodermic needle that was invented in 1855 by Alexander wood.) (10, page xxi)(9, page 7)
1855: Intubation fails: Pediatricians become concerned about the large number of children with diphtheria who die despite emergency tracheotomies. Reybard in Lyon tried to catheterize the larynx of a patient inflicted with croup caused by diphtheria, and failed. Weinlechner in Vienna tried to catheterize the laryx of a similar patient, and he too failed. (8)
|(26, page 13)|
Yet he proved the procedure could be done. Various other physicians described success with this or similar procedures between 1858 and 1880 when the Joseph O'Dwyer introduced his tube.(3, page 5) Some speculate the reason Bouchut's intubation tube (tubage de la glotte), which "set in the glottic space for a few days" was doomed to be rejected due to a bias created by Dr. Armand Trousseau, who was an ardent supporter of the operation of tracheotomy. Trousseau had previously convinced his fellow physicians that tracheotomy was the best method of creating an airway when suffocation was imminent, even with the low success rate. (12)
The main problem with Bouchut's "small tubes" is that they "did not adapt to the anatomy of the larynx and their sharp edges were a very traumatic cause of lesions to the mucosa and of intense pain." (12) (also see 26,page 13) Also of note, since the tube was short, it was barely positioned below the glottis (this would have allowed for air to leak around the tube resulting in diminished lung volumes). In the end, "Bouchut and his operation were so bitterly criticised that he became discouraged and abandoned it altogether. So effectually was it crushed out that no further investigations were made in this direction for nearly a quarter of a century." (26, page 13)
1869: First intubation during operation: Performed by Friedrich Trendelenburg (1844-1924) to prevent aspiration of blood and mucus during oral operations. (13, page 91)
1875: Blake cures poison victim: Using a device similar to Richardson's Bellows, Blake connected a reservoir of condensed oxygen to it and treated a case of acute poisoning with success. Before this time artificial respiration (often referred to as insufflation) was used mainly to treat neonatal asphyxia, but now the focus was also on treating adults. The nozzle of the device was inserted into the nostril. 1
1878: The first elective intubation: William Macewan was a Scottish surgeon who, on July 5, 1878, performed the first elective intubation on a patient "with a flexible metal tube" who was not anesthetized. "Once the tube was properly positioned, an assistant provided chloroform-air anesthetic via the tube. Once anesthetized, the patient soon stopped coughing." The physician lost confidence in his technique when a tube became dislodged and the patient expired. His success and failures would become learning points for future surgeons or physicians attempting intubation. It also should be known that, along with patient anticipation and fear, their was a lot of anxiety among physicians regarding this procedure. Surely they wanted to help their patients, but they also didn't want to cause further harm by their experimentation. Macewan, for example, practiced on cadavers prior to intubating any actual living patients. (9, page 7)
|O'Dwyer's Intubation Tube for a child 2-3 years old (23|
Tracheotomy was a viable option as an emergency airway, but it was painful and bloody for children, and the end results were not always positive. He decided another means of breathing for these children was necessary. (3, page 9-18)
He at first trialed flexible catheters into the nasal passages, yet this didn't meet his satisfaction. So he devised a tube to be placed into the larynx where it would remain. In this way, he picked up where Bouchut left off. By trial and error he tinkered with the device until it met his satisfaction. (3, page 9-18)
|O'Dwyer's set of five Tubes (26, page 19)|
He then played with longer tubes until he found the desired length. The final tube used was made of brass and lined with gold, and was accepted by the medical community. (See figures 2 and 3.) (3, page 9-18)(also see 26, pages 18-21)
A complete set was included in a box, that included sizes for different aged children, an obturator, an introducer, an extractor, and a gag. The length of the tubes in inches were 1.5, 1 3/4, 2, 2.25 and 2.5. (3, page 9-18)(also see 26, pages 18-21)
The obturator of the physicians choice is connected to the end of the introducer, and this is used to insert the tube. If necessary a small thread could be inserted and tied to a hole on the outer edge of the tube to prevent it from going down the traches, and to facilitate removal. (3, page 9-18)(also see 26, pages 18-21)
The kit also came with a scale (see figure 5) which helped the physician determined appropriate depth of the tube according to age. The scale is used like this: "The smallest tube reaches line 1, and is intended for children about one year and under. The next reaches line 2, and is for children between one and two years. The third size, marked 34 on the scale, should be used between two and four years. The fourth, marked 5-7, is for the next three years, and the largest tube is for children from eight to twelve."
O'Dwyer also designed larger tubes and equipment for adult intubation. (3, page 9-18)
1880: The Fell-O'dwyer Apparatus: Once O'dwyer intubated his patient's, he needed a mechanism to breathe for them. This task fell into the hands of George Fell, who invented a t-piece. One end of the t-piece was connected to the tracheal tube, and the other to bellows. The bellows were used to provide positive pressure breaths. Of course the problem here is it took a lot of manual labor to provide breaths for such patients. Still, the technique provided physicians an opportunity to help their patients, both when a physician needed to create an emergency airway, and when surgeons needed to perform more invasive operations. (9, page 7)
|O'Dwyer's introducer connected to obturator (23, page 16)|
1887-1888: George Fell's Apparatus (Hand Operated Bellows): In 1887 Dr. George Fell invented a system of bellows whereby the operator would use his hands to provide positive pressure breaths. He connected the bellows to either a tracheotomy or face mask. He became the first to perform this procedure on a human in a case of poisoning. (6, page 283) (22, page 3) In order to connect the apparatus to the airway, Fell invented a t-piece. One end of the t-piece was connected to a tracheal tube or mask, and the other to the bellows. (9, page 7)
1891: The Fell-O'Dwyer Apparatus (Foot operated Bellows) Once O'dwyer intubated his patient's, he needed a mechanism to breathe for them. George Fell's apparatus must have worked, yet it needed to be fine tuned for ease of use. He revised Fell's system so that breaths were provided by pressing down on a lever with his foot. O'Dwyer preferred to connect his bellow system to an endotracheal tube. O'Dwyer was concerned about over-distention of the lungs due not allowing enough time for expiration, and therefore recommended giving slow breaths, or 10-12 per minute. (6, page 283)
1891: Concerns of Intubation: By the late 19th century many of the same concerns physicians have today about intubation were considered. One such concern being the ulceration of tissue due to pressure of the tube set upon it for a long period of time. Tubes were generally taken out after six days with success, although in some cases were left in 12 days or longer. Dr. Rank, a German physician, ultimately recommended removal of the tube after 10 days, and if necessary, the physician should consider tracheotomy. Some physicians recommended extubation after the 5th day, which would be in line with modern protocols. Feeding the patient was also a concern, and was either done with soft foods or liquids, or by nasalgastric tube. It was recommended that if the tube was accidentally spit up that the nurse take advantage of the moment to try feeding the patient prior to re-introducing the tube (if the tube is still needed). (3, page 29-20)
|O'Dwyer intubation kit as advertised to physicians in 1901. (16, page 228)|
"The operation of intubation is a difficult one, because it must be done very rapidly. A period of ten seconds is not safe in some cases, and fifteen seconds would certainly produce apnea in many instances. The necessary touch and skill require much practice, and this should be acquired on the cadaver until the tube can be inserted in different subjects in about five seconds. It is much easier to perform intubation in some subjects than it is in others. After such prolonged practice, the operation may be done with comparative safety... No great amount of surgical skill is required to perform tracheotomy, but good nursing is a necessity. Intubation, therefore, calls for a trained operator, and tracheotomy for a trained nurse."(14, page 557)
|Here is another picture of O'Dwyer's Intubation kit. (26, page 27)|
1892: Dr. Gay makes pitch for intubation: Another physician, Dr. George S. Gay of Boston, said that "intubation is by no means perfect, but it possesses sufficient advantages to give it a permanent place in the treatmenet of acute laryngeal stenosis (narrowed upper airway caused by croup secondary to diphtheria). Although it will never entirely displace tracheotomy, the former has some important advantages over the latter. No anesthetic is required; there is no hemorrhage. Unless one's early experience with intubation has been particularly favorable, he is likely to prefer tracheotomy. The strongest advocates of intubation will be found among those who have had the largest experience with it. The consent of the parents to perform intubation is more easily obtained, and the operation can be resorted to earlier." (14, page 557-558)
This shows the proper position of operator and assistant.
The assistant holds the head "securely and slightly backward."
The gag should be introduced in the left angle of the mouth,
well back between the teeth, and widely opened. The operator
should then quickly seize the introducing instrument with the
tube attached, hook the loop over the little finger of the left hand,
and introduce the index finger of the same hand, closely followed
by the tube" The tube should sit in the larynx. (26, pages 38-40)
1893: Cuffed Endotracheal Tube: It must have also been discovered early on that air was leaking around the tubes, instead of inflating the lungs. Likewise, some patients must have vomited when the tube was inserted past the gag reflex, and this would have caused aspiration pneumonia, which would spell doom for most patients back then. Physicians must have sought some means of securing the airway around the tube. According to the 55th anniversary publication of the German Society of Anaesthesiology and Intensive care, Victor Eisenmenger became the first to use an endotracheal tube that had a cuff on the distal end of the tube that was connected by a pilot line to a pilot balloon. Air was inserted with a syringe into the pilot line, and both cuffs would become inflated. The physician would know the distal cuff was inflated when the pilot cuff was inflated. Such a system was soon adapted by other physicians. (13, page 91)
1896: The Fell-O'Dwyer Apparatus modified: Dr. Northrup recommended the Fell-O'Dwyer apparatus, and it was later modified by Tuller and Hallion of France, and later by Doyan. Doyan's "apparatus consisted of 'duplex' bellows (for insuflation and suction) attached to an intralaryngeal cannula. (22, page 3)
1900: Cuffed Endotracheal Tubes and laryngoscopes: Around the turn of the century cuffed endotracheal tubes (ETT) were used with increased frequency. A larygoscope was first described in 1855 using sunlight to see the vocal cords, and by 1913 a battery powered laryngoscope with an external light was invented. This was refined so it had a handle with a battery and a light bulb at the end of the scope for easy visualization of the vocal cords. (2)
1900: Oral intubation becomes popular: Initially the procedure of oral intubation must have been as nerve wracking to the physician as the patient and the patient's family. However, as with anything, the more it was performed the more confident and competent the physician became in both recommending and performing the procedure. According to a 1911 edition of the New York Medical Journal there must have been enough successes with the intubation by the mouth (per os) by 1900 that it had "found many followers." (12, page 760)
1900: Indications for intubation: As more and more physicians became comfortable with laryngeal intubation, they began experimenting with the procedure both on cadavers and on real live patients. The ultimate goal, of course, was to help patients survive diseases that otherwise would have taken their lives. By 1911 some of the indications are mentioned in the New York Medical Journal: (12, page 760)
- Operations (of the mouth, nose, throat and thorax) (12, page 760)
The tubes were of his own design. (13, page 91) As a local anaesthetic to prevent the gag reflex he used cocaine. He introduced the tube into the airway with a metal stylet. He used his the index finger of his left hand to lift the tongue and the glottic tissue, and used his right hand to insert the tube through the vocal cords. While cuffs were used by other physicians to seal the airway, he preferred to have it sealed by "positioning a supralaryngeal flange near the tube's tip before packing the pharynx with gauze." (11, page 7) (13, page 91)(also see 22, page 3)
To see a very good picture of Kuhn's procedure check out this link.
1902: O'Dwyer apparatus modified again: This modification was made by R. Matas who 'Constructed an apparatus in which a modified O'Dwyer tube was connected with an automatically acting pump. The pump contained originally two independent metal cylinders for inspiration and aspiration. However, the first experiment made on a dog convinced Matas that the suction force, exercised by the aspiration cylinder, does damage to the lungs, and he eliminated that part of the apparatus. (22, page 3)
1913: Modern laryngoscope invented: A better laryngoscope as invented by Jackson, and it was later improved by Miller and Mackintosh (see below) (14, page 372)
1914-1918: Magil invents blind intubation: During WWI Dr. Magill performed a variety of facial reconstruction surgeries. He discovered that in order to do such surgeries the patient had to be intubated. Along with Stanley Rowbotham, he developed a method of tracheal intubation. He blindly inserted one tube of gum elastic design into one nostril. In this way he coined the term "blind intubation." (24, pages 8, 753)
There were two problems with this system. One was that anesthetic gas was escaping the tube, and the operating physician was inhaling this gas. Obviously, this affected his work. The other was that blod and other debree from the operation would fall into the airway when the tube was pulled. Obviously, this was detrimental to the patient. So a two-tube system was developed. One tube was blindly inserted into a nostril into the larynx to breathe and to apply the anesthetic, and the other through the mouth into the pharynx to provide for the escape of gases. (24, pages 8, 753)
He became so proficient at his method that students from all over came to watch and learn his method. While he taught his method, other physicians continued to have trouble inserting the tubes due to patient agitation, while Magill did not. Magill had a secret that he refused to tell the students: that he used cocaine as a local anesthetic to the throat. (25, page 110)
The rubber endotracheal tubes used by Magill were standard for the next 40 years until being replaced with plastic tubes. (24, page 8)
1920: Magill Forceps introduced: In order to guide the nasal tube into the airway, Magill used forceps that still bear his name (Magill Forceps) (15, page 372)(24, page 8)
1926: Guedel experiments with cuffed endotracheal tubes: Noting the need to protect the lower airway from secretions and surgical debris, Arthur Guedel (1883-1956) performed experiments with using a cuffed endotracheal tube. His cuff was made out of rubber. His experiments also determined that the best place to position and inflate the cuff was just below the vocal cords. This, he found, was the best way of protecting the airway during intubation. One this task was accomplished, he aimed to encourage stubborn American physicians that intubation of the benefits of intubation. (24, page 8)
1926: Guedel inspires American physicians to intubate: While European physicians intubated on a regular basis during operations, American surgeons used other means. Noting the benefits of intubation, Arthur Guedel put on a show where he went around the country with his dog named Airway. He would anesthetize and intubate his dog, and then submerge it under water. Just as the audience suspected the dog was dead, he would pull it from the water, extubate it, and the dog would shake off the water and run off. These shows became known as the Dunking Dog Shows proved that intubation not only allowed the physician to breathe for the dog, but the inflated cuff prevented water from getting into the dogs lungs. These efforts worked, as American physicians soon became proficient in intubation. (25, page 111)
1930: Oral Airway Introduced: Ralph Waters (1883-1979) introduced the flattened oral airway, and it was later modified by Guedel by fitting the oral airway with a "rubber envelope in an attempt to reduce mucosal trauma." (24, page 753)
1932: One lung intubation introduced: Ralph Waters accidentally allowed an endotracheal tube to slip all the way into a patient's lungs, and he inflated the cuff. In this way he learned that one lung could be intubated with a long endotracheal tube while the other was operated on. This made it possible to do lung operations. (24, page 8)(25, page 111)
1942: Anesthesia during intubation: By the 1880s intubation was being increasingly used for children with airway stenosis secondary to croup secondary to diphtheria. As a physician observed that the patient was going to suffocate to death unless he did something, the choice was offered to the parents: intubation or tracheotomy? (2, page 227) (19, page 1674)
Intubation must have presented as the best option in many cases, as the procedure would avoid a cut of the throat. A problem that continued was the procedure caused quite a bit of anxiety on the part of the patient, as you might imagine. If the child fought the efforts of the physician, this could make the procedure very difficult to perform. (2, page 227) (19, page 1674)
Cocaine was occasionally used as a local anesthetic to prevent the gag reflex, and general anesthetics were occasionally used to paralyze the patient, although these were only used if the physician was familiar with them and comfortable with their use. (2, page 227) (19, page 1674)
In 1942, Harold Griffith, A Canadian anesthesiologist, made a major breakthrough in this regard on January 23, 1942, when he and his assistant, Dr. Enid Johnson (also an anesthesiologist) used Curare to paralyze a patient prior to intubation. He used it as an anesthetic in 23 operations, and wrote a report on his successes with it. (2, page 227) (19, page 1674)
This was a major breakthrough because it allowed the surgeons to sedate and ventilate patients during the operation. (2, page 227) (19, page 1674)
WWII: Intubations proficiency increases worldwide: In preparation for the traumas generally associated with battle wounds, anesthesiologists practiced and became very proficient at performing the procedure of intubation. The methods learned became standard practice, and oaver time intubation training became a regular part of a physician's training. (25, page 753)
1964: Plastic endotracheal tubes introduced: They were actually made of polyvinylchloride (PVC) with an inflatable cuff. Rubber tubes tend to harden when exposed to body temperature. PVC tends to soften at body temperature, and is therefore less likely cause damage to tissues of the airway. The tubes are also clear and opaque. They come with markers so caregivers know how far down the tube is inserted.
1970: High volume, low pressure cuffs introduced: Previously, cuffs were low volume high pressure. When inflated, these cuffs came into contact with very little area of the trachea, and created a great seal. However, due to the high pressure, risk of cutting off circulation and causing necrosis was high. High volume, low pressure cuffs would come into contact with more tracheal tissue, although the lower pressure was less traumatic. Surely the cuff pressure would have to be minimized, and the cuff may need to be rotated up or down 1-2 cm on a regular basis to minimize tissue damage, yet this was a much better set up than the older cuffs. The drawback is the seal is not ideal.
Conclusion: So you can see that physicians were slow to begin using intubation, although experiments by the few, in an attempt to help their patients, resulted in both an improvement in the technique used and the equipment available. By the 1940s intubatoin during surgery would become standard, and by the 1950s the procedure became standard in across the medical spectrum, including at on the scene of an accident and emergency rooms.
Likewise, while fireside bellows remained the preferred method of providing breaths through the endotracheal tube, the quest was ongoing to find a mechanical device that would provide breaths in a means that was less laborious for the provider, and safer for the patient.
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- Waxham, F.E., "Intubation of the Larynx," 1888, Chicago, published by Charles Traux (Waxham was an early proponent of intubation for diptheria and croup.
- Gould, George M, "American Year-book of Medicine and Surgery," 1899, Philadelphia, W.B. Saunders
- Curry, James, "Observations on Apparent Death from drowning, hanging, suffocation by noxious vapours, fainting-fits, intoxication, lightning, exposure to cold, & etc., and an account of the means to be employed for recovery. To which are added the treatment proper in cases of poison, with caution and suggestions respecting various circumstances of sudden danger," 2nd edition, 1815, London (the 1st edition was published in 1792)