More on Ethylene: Anesthetic Gases Part I
The Introduction and Popularity of Ethylene as an Inhalational Anesthetic.
Highlights from two articles one from 1927 and the other from 1930 when Ethylene as an anesthetic gas began to become popular with some surgeons in America. Ethylene as an anesthetic is now primarily a historical or academic interest, but the overall history of anesthetics is a crucially important one. In an article “Inhaled anesthetics: an historical overview” published in Best Practice & Research Clinical Anaesthesiology (Vol. 19, i. 3) in 2005 the authors sum up ethylene as a failure. In their brief medico-historical overview their summation of ethylene is the following:
Ethylene gas had been used to inhibit the opening of carnation buds in Chicago greenhouses, and in 1923, it was speculated that there might be an anesthetic action on humans. Ethylene was not a successful anesthetic because high concentrations were required, it was explosive, and it had an unpleasant odor.
I think this curt conclusion is too much of a simplification, as the authors themselves note “all volatile anesthetics of this period were explosive save for chloroform, who’s hepatic and cardiac toxicity limited use in America. Anesthetic explosions remained a rare but devastating complication for both the anesthetist and the patient.” I have selected just these 2 excerpts to demonstrate the personal excitement these physicians had to using ethylene in their practice (and perhaps on themselves?).
ETHYLENE AS AN ANESTHETIC FOR GENERAL SURGERY
By Cabot, Hugh, and Ransom, Henry K., Ann Arbor. Ann. Surg., August, 1927, lxxxvi, 255 http://www.sciencedirect.com/science/article/pii/S0002961027913646#
Ethylene has all of the advantages of nitrous oxide and oxygen and also gives greater relaxation and avoids objectionable cyanosis. It appears to be remarkably free from danger except that possibly resulting from explosions. It will not give complete muscular relaxation particularly for operations in the upper abdomen, and if this is required, it must be combined with local or regional anesthesia if it is used. In the author’s practice it has practically pushed nitrous oxide from the field and will, they believe, for ordinary surgical practice, supersede it. It is not an anesthetic which can be employed except where trained anesthetists are on hand and a rather cumbersome apparatus is available. It is not likely, therefore, to supersede ether or chloroform for use outside of hospitals, but for general hospital practice, it has outstanding advantages.
ETHYLENE—THE NEW GENERAL ANESTHETIC
By M. M. Dillard, M.D., Anesthetist and Cardiologist, Dailey Hospital and Sanitarium, Chicago, Illinois.
Journal of The National Medical Association Vol. XXII, No. 1 (pg. 10–11), 1930.
Only a few years ago, chloroform was the anesthetic of choice. It was pleasant to take, but by no means fool-proof within the hands of the inexperienced, but by a minor degree of practice, one may acquire the art of administering it with facility. Due to the many postoperative complications, and occasionally a sudden death, chloroform as a general anesthetic has about been discarded.
While ether has long been known to surgeons as the safe anesthetic for complete relaxation, it has never yet gained favor or made friends among those who have taken it. My experience with ethylene covers over 800 cases in the general field of surgery: the eye, ear, nose and throat, obstetrics, and dentistry, and I have no hesitation in naming it as the anesthetic of choice. It has further proved that since my using the ethylene oxygen anesthetic, it has become more in demand by surgeons and the laity as well. We can readily realize that for any new anesthetic to come into the field of existence and continue to make steady progress, it must have definite advantages over all others. Ethylene as an anesthetic possesses the following outstanding advantages:
1. Its ease of induction, and rapidity of anesthetic recovery—Complete anesthesia may be induced within three to eight minutes with ethylene,usually without any excitement or feelings of suffocation. The recovery following operation is usually just as rapid, so quickly until morphine has to be given in many cases immediately after the mask is removed, to control post-operative pain. Relaxation produced is sufficient for all ordinary operations outside the abdominal cavity; but, in order to obtain the proper relaxation for intra-abdominal operations, especially the upper abdomen, it is often necessary to use in conjunction some ethei at the beginning of the operation; also while there is much handling of viscera. In my experience, one ounce of ether is usually sufficient for operations lasting from one to two hours, and this doesn’t retard the return of the patient to consciousness.
2. Relaxation without cyanosis-Relaxation can be obtained without cyanosis much more readily than when nitrous oxide or any other gas anesthetic is used. Luckhardt states that the color of the patient is nearer normal than when any other inhalation anesthetic is used.
3. Ethylene is less toxic on the nervous system or body cells, and thereby seldom produces headaches, as is the custom with nitrous oxide gas.
4. Absence of respiratory irritations-Ethylene is now used in many clinics on all operative cases with pulmonary tuberculosis, asthma and kindred diseases, where it is highly desirable to avoid further lung irritation. There is no increase in the flow of saliva or mucus along the respiratory tract, even though the patient has not had atropine previous to operation. Dr. Donald C. Balfour of the Mayo Clinics recommends the use of ethylene for all operations upon the stomach, feeling that the toxicity from anesthesia will be reduced to a minimum.
5. Less acidosis […]
6. Freedom from post-operative sweating—After one or two hours of complete anesthesia, the patients garments are dry and rarely need to be changed. Patients are not dehydrated during the operation; and we believe that this is one of the strongest considerations favor of ethylene, for when the patient remains dry during the entier process of operation, it prevents chilling, thereby preventing postoperative lung complications.
7. Less nausea and vomiting—If the patient vomits at all, it usually occurs at the time the patient awakens and while he is still on the operating table. it is always very transitory and occurring after the reflexes have returned, thus the patient does not aspirate the vomitus.
8. Gas pains-Luckhardt and Lewis of Chicago made a careful survey of 119 cases given ethylene oxygen, and noted that gas pains were only in 4.2% operated upon, whereas 36.6% of the patients operated upon with ether anesthesia suffered this particular discomfort.
9. Blood pressure-Several authorities, Heaney of Chicago, Allgeyer of New Orleans, and Aurelius of Minneapolis, declare there is very little change in blood pressure during an ethylene anesthesia. Usually there is a rapid rise, the first ten or fifteen minutes to twelve or fourteen m. m. of mercury, after which it gradually recedes to normal. Hypertensive cases usually do fine under ethylene.
10. Coagulation time of the blood-Recent investigation shows that the coagulation time of the blood is very much decreased under ethylene anesthesia, which disproves the former idea that ethylene increases bleeding. An author cites cases in which the coagulation time was 14 minutes at the beginning of the operation and at the close it had been reduced to six minutes, and remained so for six days after operation.
There are two main disadvantages of ethylene: (1) Odor. (2) Danger of explosion. The odor is only complained of by some when the gas is first introduced in the operating room, but after its continued use, it is scarcely noticeable, except by newcomers. Ethylene is inflammable and is said by many to be highly explosive. The thermo-cautery should never be used on a patient, to whom ethylene is being administered; neither should ethylene be given in the x-ray room, or near open flames. Experiments worked out by Brown of Toronto show that it is neither safe to use a cautery in the midst of ether vapor, as he has been able to prove that vaporized ether ignites in the presence of an open flame, as readily as the ethylene gas. In concluding, ethylene and oxygen anesthesia is highly suitable for every type of operation, and is of inestimable value in operative obstetrics, without the addition of ether. It is nonirritating to the lungs and kidneys. It has no post-administrative effects on the hemoglobin of mother or child. It can be given without asphyxia or jactitation. The patient quickly returns to consciousness. If vomiting occurs, it is usually insignificant and transitory. It does not produce paralysis or peristalsis and there is as little post-operative complaint as we meet after local anesthesia. One of the most unpleasant complications following anesthesia is the development of an acidosis, a day or so after operation. This condition is due to the accumulation of ketone bodies in the blood and as Thaihimer so neatly demonstrated, may be promptly relieved by the administration of insulin. Ethylene anesthesia, well given, serves to eliminate time lost in cases of poor risk and enables the surgeon to work with ease and freedom, and is relieved of the task of controlling the psychic element of the patient that usually accompanies local anesthesia.