ACE mixture is an historical anaesthetic agent for general anaesthesia. It was first suggested by George Harley [1] and first used in England around 1860. In 1864 it was recommended for use by the Royal Medical and Surgical Society's Chloroform Committee. It was rarely used after the 19th century, except in Germany, where it was used for slightly longer. [2]
It was a mixture of alcohol, chloroform and ether [1] [3] which gives the mixture its name. Its effects were said to be between that of chloroform and ether and it was used when ether alone was contraindicated. [1] Its boiling point was given as 48°C. [4] Its actual safety margin over its components alone was marginal. [5] [6]
ACE mixture was most commonly made up in the ratio: 1 part alcohol, 2 parts chloroform, and 3 parts ether [2] although other ratios existed. See 'other preparations' below.
Chloroform (which was first used in 1847) used on its own produces myocardial depression, however the excitatory properties of the alcohol and ether contained with the chloroform in the ACE mixture was believed to reduce this. [2] However, some did question this experimentally at the time. [7]
Many anaesthetists favoured ACE mixture and one author in 1887 in the British Medical Journal considers the ACE mixture, at the time, the best anesthesia for general use and use in childbirth. He states one downside; the "excited" state of patients on regaining consciousness after the anaesthetic, due to the alcohol in the mixture. [8] Another downside of the mixture, as with most anaesthetics at the time, was its high flammability.[ citation needed ]
Deaths have been known to occur from the mixture. [5] [9] However, fewer deaths from ACE mixture were reported than deaths from chloroform or ether. [6] [10]
After widespread use of ACE mixture, anaesthetists would try different mixtures for different patients and different procedures. CE mixture omitted the alcohol and AC mixture omitted the ether. [1] One doctor described using equal parts alcohol and chloroform in minor operations, but chloroform with Eau de Cologne (which has a high alcohol content) in dental procedures for a more pleasant experience. [11]
Despite the similar names, the anaesthetic mixture named "bichloride of methylene" did not contain the actual compound that would be called bichloride of methylene (Dichloromethane CH2Cl2). Instead, it was later discovered as a mixture of chloroform and alcohol marketed as the bichloride of methylene and even given the formula CH2Cl2. [12]
Other mixtures were: [1]
Preparation Name | as written in source | Reduced ratio of Alcohol | Reduced Ratio of Chloroform | Reduced Ratio of Ether |
---|---|---|---|---|
Common mixture | 1 part alcohol, 2 parts chloroform, and 3 parts ether | 1 | 2 | 3 |
Richardson's mixture | 20 parts alcohol, 12 chloroform and 8 ether | 5 | 3 | 2 |
Vienna mixture | 0 parts alcohol, 31 parts chloroform and 23 parts ether | 0 | 31 | 23 |
Billroth's mixture | 1 part alcohol, 3 part chloroform and 1 part ether | 1 | 3 | 1 |
Linhart's Mixture | 20% alcohol with chloroform | 1 | 4 | 0 |
Methylene ("Bichloride of methylene") | 30% methylic alcohol and 70% chloroform | 3 | 7 | 0 |
Not included in table as they include petroleum ether in addition to diethyl (sulphuric) ether:
ACE mixture was also used to anaesthetise animals, including in preparation for vivisection. [13]
ACE mixture could be given through drops (from a drop bottle [5] ) on a piece of lint (a towel), in a Rendle's mask, a cone, or through an inhaler.
Inhalers included: Allis' inhaler, Junker's inhaler (with a funnel mask) for children, Clover's inhaler with bag removed (this inhaler has to be constantly lifted from the face to allow 'free air' to be admitted). Ellis proposed an inhaler to blend vapours in exact proportions, however it was impractical, but Gwathmey modified his idea and created a practical apparatus. Tyrrell created a similar idea called the 'Tyrrell's double-bottle method'. [1]
Anesthesia is a state of controlled, temporary loss of sensation or awareness that is induced for medical or veterinary purposes. It may include some or all of analgesia, paralysis, amnesia, and unconsciousness. An individual under the effects of anesthetic drugs is referred to as being anesthetized.
Chloroform, or trichloromethane (often abbreviated as TCM), is an organic compound with the formula CHCl3 and a common organic solvent. It is a very volatile, colorless, strong-smelling, dense liquid produced on a large scale as a precursor to PTFE and refrigerants and is a trihalomethane that serves as a powerful anesthetic, euphoriant, anxiolytic, and sedative when inhaled or ingested. Chloroform was frequently used as an anaesthetic between 1847 and the first half of the 20th century. It is also part of a wider class of substances known as volatile organic compounds. Chloroform is miscible with many solvents but it is only very slightly soluble in water (only 8 g/L at 20 °C).
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General anaesthesia (UK) or general anesthesia (US) is a medically induced loss of consciousness that renders the patient unarousable even with painful stimuli. This effect is achieved by administering either intravenous or inhalational general anaesthetic medications, which often act in combination with an analgesic and neuromuscular blocking agent. Spontaneous ventilation is often inadequate during the procedure and intervention is often necessary to protect the airway. General anaesthesia is generally performed in an operating theater to allow surgical procedures that would otherwise be intolerably painful for a patient, or in an intensive care unit or emergency department to facilitate endotracheal intubation and mechanical ventilation in critically ill patients.
Anesthesiology, anaesthesiology, or anaesthesia is the medical specialty concerned with the total perioperative care of patients before, during and after surgery. It encompasses anesthesia, intensive care medicine, critical emergency medicine, and pain medicine. A physician specialized in anesthesiology is called an anesthesiologist, anaesthesiologist, or anaesthetist, depending on the country. In some countries, the terms are synonymous, while in other countries they refer to different positions, and anesthetist is only used for non-physicians, such as nurse anesthetists.
An inhalational anesthetic is a chemical compound possessing general anesthetic properties that can be delivered via inhalation. They are administered through a face mask, laryngeal mask airway or tracheal tube connected to an anesthetic vaporiser and an anesthetic delivery system. Agents of significant contemporary clinical interest include volatile anesthetic agents such as isoflurane, sevoflurane and desflurane, as well as certain anesthetic gases such as nitrous oxide and xenon.
Sir James Young Simpson, 1st Baronet, was a Scottish obstetrician and a significant figure in the history of medicine. He was the first physician to demonstrate the anaesthetic properties of chloroform on humans and helped to popularise its use in medicine.
A halogenated ether is a subcategory of a larger group of chemicals known as ethers. An ether is an organic chemical that contains an ether group—an oxygen atom connected to two (substituted) alkyl groups. A good example of an ether is the solvent diethyl ether.
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Methoxyflurane, sold under the brand name Penthrox among others, is an inhaled medication primarily used to reduce pain following trauma. It may also be used for short episodes of pain as a result of medical procedures. Onset of pain relief is rapid and of a short duration. Use is only recommended with direct medical supervision.
Curt Theodor Schimmelbusch was a German physician and pathologist who invented the Schimmelbusch mask, for the safe delivery of anaesthetics to surgical patients. He was also a key figure in the development of mechanical methods of sterilisation and disinfection for surgical procedures, on which his Anleitung zur aseptischen Wundbehandlung was considered a seminal work.
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Throughout recorded history, attempts at producing a state of general anesthesia can be traced back to the writings of ancient Sumerians, Babylonians, Assyrians, Egyptians, Indians, and Chinese. Despite significant advances in anatomy and surgical technique during the Renaissance, surgery remained a last-resort treatment largely due to the pain associated with it. However, scientific discoveries in the late 18th and early 19th centuries paved the way for the development of modern anesthetic techniques.
The Chloroform Committee was commissioned by the Royal Medical and Chirurgical Society in 1864 to investigate the use of chloroform. The committee recommended the use of chloroform in the same year. It was the first of such committees and concluded that chloroform depresses the action of the heart and frequently kills. One of the members, Joseph Clover, during his time on the committee developed apparatus for using chloroform called the Clover bag.
The Special Chloroform Committee of the British Medical Association was established in 1901 following the annual meeting of the British Medical Association and it produced its last final report 1910.
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James Robinson was a British dentist and anaesthetist. On 19 December 1846, he became the first person to carry out general anaesthesia in Britain when he administered ether to a patient undergoing a tooth extraction. The next year, he published A Treatise on the Inhalation of the Vapour of Ether, perhaps the first textbook of anaesthesia. Robinson's work influenced the prominent anaesthetist John Snow. Robinson also undertook initiatives to reform the dental profession in Britain. At the age of 48, he died of blood loss following a gardening accident; his London home, as well as the site where he first administered anaesthesia, are commemorated with plaques.