In an operating room, an anesthesiologist injects a fluid in one of the patient’s veins; within seconds, the latter loses consciousness and the operation commences. When the patient wakes up, all s/he can remember is the injection; it feels as if nothing else happened. Nevertheless, things were not always that easy. Surgical operations before anesthesia were a nightmare for patients and surgeons; a surgeon once compared the operating theater to an execution room.
In the old days, patients were struck on the head to lose conciousness, or alternatively held down by strong people until the surgeon completed the operation. Other surgeons resorted to cutting the blood supply to the organ, so that it would die out, making it easier to remove. Others would apply ice to the area to numb it before operating; medical plants and herbs were also used in anesthesia, but applying too much had a negative effect, making it dangerous. Alcohol was discovered by accident due to the fermentation of fruits; its vapors were used in anesthesia due to its pain-relieving effect.
Modern anesthesia emerged when the English scientist Joseph Priestley discovered Nitrogen dioxide (NO2), known as laughing gas. Dentists were the first to use it as an anesthetic, to address the pressing daily problem they faced with their patients during teeth extraction. On 16 October 1846, a surgeon at Massachusetts General Hospital, Boston, managed to remove a tumor from a patient’s neck using an ether gas discovered by the American dentist William Morton. Marking a huge milestone in the history of anesthesia, the International Day of Anesthesia is celebrated annually on that day. Prior to 16 October 1846, pain and surgery were two sides of the same coin.
After that, ether became a popular anesthetic; still, it had side effects, including nausea, vomiting, and inflammation of the lungs. It also took a long time to function before the surgeon could start operating; these drawbacks urged the search for better alternatives. Scottish obstetrician Sir James Simpson discovered chloroform and used it during a childbirth operation. Chloroform had advantages over ether; it was faster, stronger, and cheaper. The fact that it was used during the childbirth of Queen Victoria to Prince Leopold made it more popular among surgeons and patients. However, it lost its reputation after its side effects on the liver appeared and deaths associated to it increased.
Later, many types of general and local anesthetics emerged, allowing doctors to choose according to the status of the patient and the type of operation. Patients lose feeling and conciousness entirely in case of using general anesthetics, the most popular of which are:
- Thiopental: It was discovered in the 1930s and is injected in the veins. It is merited for its rapid effect; however, it is short-termed, so after it is injected, the patient still has to be anesthetized using another drug.
- Halothane: It was discovered in the 1950s; it works through inhalation and is amongst the most widely used anesthetic drugs until now.
- Isoflurane: It is similar to Halothane, yet with the added advantage of being suitable for patients who suffer from liver diseases.
- Propofol: Discovered in 1977, it is one of the newest anesthetics; it is injected in the veins.
As for local anesthetics, they make patients lose feeling in a specific area, keeping them concious and alert; major examples include:
- Cocaine: It is the oldest local anesthetic; extracted from the leaves of the coca plant, it is the only naturally-existing anesthetic. Cocaine was discovered in South America, and was widely used during the 17th century in dentistry and ophthalmology.
- Lidocaine: It is the most widely used local anaesthetic until today, and is a derivative of Cocaine.
Later, spinal anesthesia emerged; it works on the lower region of the body. A local anesthetic, such as Bupivacaine, is injected in the spinal cord fluid in the lower part of the body; the patient loses feeling in the lower region of the body, but remains alert. This type of anesthesia is widely used in Caesarean section surgeries.
As science develops, new drugs emerge. These have included muscle relaxants, which prevent spasms during surgeries; antiemetics, which prevent salivation to protect the patient from suffocation; and antibiotics, which the patient takes before or after surgery. All this has made surgery much easier, decreasing the complications that could occur during or after the operation.
In spite of all the breakthroughs in anesthesiology, thanks to which millions of surgeries are performed annually around the world, Mankind is in a continuous quest to find what is better and safer.
References
medicalnewstoday.com
medlineplus.gov
medscape.com
ncbi.nlm.nih.gov
sciencedirect.com
The article was first published in print in SCIplanet, Winter 2020 issue.
Cover image by wavebreakmedia_micro on Freepik