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held two inches above the patient's face. The drug is dropped from an ounce glass-stoppered bottle, drop by drop, around the top of the mask. The lower part is always left dry to admit a large amount of air. As the patient becomes accustomed to the fumes and the irritation ceases, which is shown by regular breathing and absence of swallowing, the mask is gradually lowered and the dropping increased in frequency until full anesthesia is attained. An occasional drop will continue this stage.
This method allows of free air mixture, lessens the excitement stage and its unpleasant incidents and dangers, and allows perfect control of the patient at all times.
The methods and appliances for the administration of ether are quite numerous. From my experience and the experience of anæsthetists all over the country, I have come to the firm opinion that we are not in need of appliances, new or old, fitted with stop-cocks and valves to make the administration more pleasant and less dangerous, but we do need better anæsthetists. Every college should give its students practical training by means of personal supervision of every anæsthetic administered in the clinics. The student giving the anæsthetic should be watched and instructed by the college anæsthetist. This system has been in vogue in our college for the past three years, but is not found in many colleges of the country.
In many hospitals the closed method of ether administration is in use, and has been for years. I think this accounts for the unpopularity the drug holds in these institutions, because the results in the operating room and following the operation are not good. Ether administered by the “open method” has become almost an ideal anæsthetic, pleasant and safe, so much safer than chloroform, that I think it ought to be given in all cases, unless strongly contraindicated.
The “open method” is as follows: An Esmarch inhaler is cov-ered with two thicknesses of stockinetting. The drug is dropped from
a glass stoppered bottle, and as much care used in the beginning to - avoid frightening the patient by choking and smothering as in the drop method with chloroform. As the patient passes into the second stage, an additional covering of four to six layers of gauze is added. When full anæesthesia is attained, more air is admitted by raising the edges of the covering. Should the patient show signs of vomiting, the edges are held down tight and more ether added to the mask.
Advantages claimed over other methods are, simplicity, readiness, cleanliness, less excitement and struggling, less involvment of lungs and kidneys, less vomiting afterward, quicker return to consciousness and requires less of the drug. I invite any auditor to take a closed cone, pour into it an ounce or two of ether, as is commonly done, and place the mask firmly over his own face. If the resulting sense of suffocation is not sufficient to make him a convert to the open method I shall despair of converting by other argument. The early struggles. of the ether patient, that you have witnessed, is a fight for air and, tohis excited imagination, is one for his life.
When the closed method is used, I would insist on the anæsthesia being induced primarily with nitrous oxide, or the following procedure used: Before going to the operating room, the patient is given. a glassful of water. When the operation is completed and before the patient is removed from table, a stomach tube is passed and the stom-ach lavaged. Experiments show that ether is excreted from the blood into the stomach and this, with the amount swallowed, produces severegastritis.
Heated operating tables and careful covering of patient as he is. wheeled through cold, draughty halls from a warm operating room, will prevent many pneumonias commonly attributed to ether.
One of the most difficult feats an anæsthetist has to perform is: the administration of an anæsthetic where the site of operation is in, or contiguous to, the buccal cavity.
Junker's method is this: A preliminary tracheotomy is per-formed, tubes extended to a bottle to which is attached a hand bulb. Each pressure of the bulb vaporizes 11/3 drop of chloroform, which is forced into the lungs. The pharynx is packed to prevent swallowing of blood, and a clean field is left above.
Crile's method is superior in that it does not require tracheotomy, with its dangers, and the anæsthetic drug is not introduced so abruptly into the lung. The details of Crile's method are as follows:
1. Full surgical anæsthesia.
3. Two drain tubes passed through nares to level of epiglottisdiameter 18 and 1/4 inch, the larger the better, tubes severed at equal: distance from nose and attached to a funnel packed with gauze.
4. The entire pharynx is then packed with large pieces of gauze. The ends must be kept in ready reach for instant removal if vomiting occurs.
6. If thoroughly done, the base of the tongue is drawn forward, leaving an air chamber just above the epiglottis. Care must be taken that the funnel is kept at a lower level than the nose, otherwise chloroform in liquid form may run into the throat.
Ethyl chloride is more familiar to most of us as a local than a general anæsthetic. Because of its being of pleasing odor and easily in- haled, and the rapidity of its action, it is gaining favor as an office anæsthetic, and as a beginner for ether. It is given through a Tieman's mask. The ethyl chloride is sprayed, one c. c. at close intervals until anæsthesia is produced. The time necessary is from one to two minutes, and anæsthesia may be continued several minutes. Lasts two minutes after drug is removed. It requires the same preparation of patient that ether does, and should never be given unless its dangers are kept in mind. It is a suitable anæsthetic for the opening of boils and abscesses, tonsillotomy, and other minor operations. .
The advantage over nitrous oxide is that it is not bulky, and is a staple compound if kept in the dark. Its disadvantages are: The drug is expensive, is not so well understood as other anæsthetics, and is still in an experimental stage. It does not produce muscular relaxation.
Nitrous oxide gas is our oldest anaesthetic, dating from 1844. In that year Horace Wells, a Hartford dentist, heard a lecture by Prof. Calton on Nitrous Oxide Gas. In illustrating the lecture, the gas was administered to a person in the audience. The man fell to the floor, but was insensible of his fall, confessing afterward that he was absolutely unconscious. This episode caused Wells to think that perhaps the gas could be utilized in dentistry for the painless extraction of teeth. With the true courage of his convictions, he tried the experiment on himself, inhaling the gas, and having his own teeth extracted by his associate. Recovering consciousness, he shouted, “A new era has dawned upon the whole world. I did not feel it more than a pin prick.” And Horace Wells was a greater prophet than he ever dreamed himself to be in the wild moment of excitement.
Nitrous oxide, nitrogen monoxide, is a colorless, transparent gas of neutral re-action, and almost odorless, made by heating ammonium nitrate in a flask or retort which decomposes it into nitrous oxide gas and water. May be liquified by pressure, converting again into gas when released. It is carried in tanks. :
The physiological action as summarized by Hare and Czerna is as follows: It causes a rise in arterial pressure, followed by a fall, the rise being due to vasomotor stimulation and the fall to vasomotor palsy. There is also marked slowing of the heart, which is believed to be due to stimulation of the inhibitory centre in the medulla oblongata. Finally, the slow pulse is changed into a very rapid one, due to vagal palsy. The addition of oxygen in the experiment prevents the rise of arterial pressure usually produced by the gas, but does not interfere with pulse rate or force. For this reason it is believed that the action of the remedy upon sensation and the vasomotor system is separate from that upon the heart and its supplying nerves.
Under the administration of the gas, the blood corpuscles darken: markedly and the cyanosis is due to this and the diminution in the amount of oxygen present. There is no chemical conversion of the gas circulating in the blood. It enters the body and leaves it as nitrous oxide. The oxyhæmoglobin spectrum of the blood is unaltered. In complete narcosis there is a change in the calibre of the renal vessels to correspond with the change in arterial pressure. Renal secre-tion is rapidly lessened, and transitory albuminuria and glycosuria may occur.
In practice, the administration of air, or oxygen, simultaneously with the nitrous oxide gas, counteracts all the bad effects noted in the above experiments. If enough air were admitted to equal 6 per cent. oxygen, there would not be enough nitrous oxide (60 per cent) to produce the desired result. Therefore, I use the pure oxygen gas, starting with 2 per cent and increasing to 6 or 8 per cent, if required, the amount of cyanosis being the guiding symptom. The oxygen lessens cyanosis and anoxæmic convulsions.
This anæsthetic is the safest one known, the mortality being almost nil. McCardie says that in the United States, where it is used extensively, the mortality is less than 1 in 1,000,000. It has proven an ideal anæsthetic for dental surgery, allowing of the sitting posture. and not requiring preliminary preparation on the part of the patient. Anesthesia is produced in from one to two minutes, can be continued an hour, if necessary, and consciousness returns in two minutes when discontinued.
In but a very few cases are there any unpleasant after-effects, which when present, consist of headache and nausea. In very recent years surgeons have become interested in it for use in minor operations and in major operations where other anesthetics were contraindicated. I have administered it for the following operations : circumcision, varicocele, hydrocele, herniotomy, drilling of antrums, dental extractions, tonsillotomy, simple laparotomy, and amputations of the extremities. The results were very good. Where rigidity remains a disturbing factor, I overcome it by administering a few drops of chloroform.
Nitrous oxide is indicated where there is disease of the heart, kidneys or lungs, but is contraindicated if there is degeneration of vessel walls, as rupture is liable to occur from the increased pressure produced. Hare cites two cases of apoplexy occurring during administration of nitrous oxide. Women and children are the best subjects, while robust men, especially heavy smokers and drinkers, take it poorly. It does not produce so profound anæsthesia as the ether and
chloroform, so I would recommend the nitrous oxide-ether sequence in operations requiring time and careful work.
Results from this method have been of the very best. The advantages are: Saving of time (anästhesia produced in five minutes), no excitement stage, less ether required, no swallowing of ether, therefore no after-vomiting and gastritis, and less kidney involvment.
1. Sajous' Encyclopedia.
M. H. Castle, M. D.-Nitrous oxide has been used largely by dentists for extraction of teeth and removal of live pulps. Recently, however, surgeons have availed themselves of this valuable anæsthetic not only for short operations but for operations extending over a period of from one to two hours. The old method of administering air with the nitrous oxide has been supplanted by the use of oxygen with nitrous oxide. When air is given with nitrous oxide, the patient is partially asphyxiated and the anæsthetic must be removed from the patient at intervals. The result of this method was prolonged partial asphyxiations. A mixture of nitrous oxide and 10 per cent oxygen produces no asphyxia, proving that the combined use of these two agents has purely anæsthetic properties. The mechanism of the recent anæsthetic apparatus permits of giving the exact proportion of the two gases. The great advantage in the use of oxygen is that a longer and more profound anæsthesia is obtained, free from anoxæmic convulsions and cyanosis. The gas is free from odor and taste, insuring a freedom from the period of excitement so noticeable in the old method. The percentage of oxygen required varies with the patient. In some 2 per cent oxygen and 98 per cent nitrous oxide produces a beautiful anæsthesia free from excitement, struggling and cyanosis, with patient perfectly relaxed. In other cases it may be necessary to tise 10 per cent oxygen and 90 per cent nitrous oxide to produce a perfect anæsthesia.
Care of the patient prior to operation is same as any other general