Surgeons, often portrayed as heroes in Korean medical dramas, have taken over the surgeries once performed by medieval barbers. The development of anesthesia has reduced pain and advanced surgery by leaps and bounds, and we discuss the principles of modern anesthesia and its potential for future development.
Yong Pal Yi, White Tower, New Heart, Good Doctor. Surgeons in today’s popular Korean medical dramas are gods in the operating room. They successfully complete complex surgeries and save patients’ lives, impressing the public with their feats. While these images have helped turn surgeons into heroes, the real world of medicine involves a lot of preparation, collaboration, and trial and error. It’s hard to accept that in the Middle Ages, barbers did the work of surgeons in such a fancy and important way. In less than 200 years, surgery has come a long way, thanks to advances in antiseptics, blood transfusions, hemostasis, treatments for bacterial infections, and anesthesia.
What does it mean to be a competent surgeon? In the past, the most competent surgeon was the one who could get the surgery done as quickly as possible. In fact, some surgeons had the skill to amputate a broad leg in three minutes. Presumably, the lack of anesthesia meant that surgeries had to be shortened to reduce pain, and time was also important to prevent complications such as infection. What’s interesting here is that these early surgeons had to exert tremendous concentration and physical strength just to win the race against time. The fact that their skills weren’t just limited to physical ability also ties in with the advancements in anesthesia that would soon follow.
In the past, anesthetics didn’t exist, but there were ways to produce similar effects. Some of the more radical ones involved beating people into unconsciousness before performing surgery, but others were more advanced. Ancient Egyptian and Assyrian doctors performed surgery by simultaneously compressing the two carotid arteries in the neck to reduce the amount of blood flowing to the brain, cutting off the supply of oxygen and rendering the patient unconscious. The Egyptians discovered that opium, a type of narcotic, relieved pain, the Assyrians created their own painkillers by mixing belladonna, cannabis, and mandrake root, and medieval Arabs developed inhalation anesthetics.
Thanks to the accumulated knowledge of so many ancient civilizations, our understanding of anesthesia is beginning to deepen, but at the time, there was a lack of understanding of why these methods were effective or how they worked. When did anesthetics in the modern sense first appear? The first was nitrogen dioxide, also known as laughing gas. In the late 18th century, Joseph Priestley first isolated nitrogen dioxide, and Sir Humphrey Davy discovered that the gas had an anesthetic effect in addition to drowsiness. At the time, however, it was thought to be more of an amusing side project than a medically significant invention. However, a dentist in the United States used laughing gas to painlessly pull out a patient’s tooth, spurring the introduction of anesthetics in many fields. Nitrous dioxide was followed by diethyl ether, chloroform, and many other anesthetics.
However, not all anesthetics are safe. In the case of chloroform, it has the advantage of being less flammable than ether, but it can cause many problems. It’s also a narcotic, which means that if you don’t use the right amount, it can cause addiction or even death. Looking back in history, the discovery of anesthetics seems to have been quite accidental. The fact that such an important discovery sometimes stems from experimental curiosity is a great example of how science evolves. So, how does anesthesia work?
There are many different types of anesthesia that are currently used to anesthetize different parts of the body, but in this article, we’re going to talk about general anesthesia. In general anesthesia, the main site of action for anesthetics is the Reticular Activating System in the soft brain. This is the part of the brain that connects the brain and spinal cord, and it is directly related to life because it supports movements that are directly related to survival, such as breathing and circulation. The reticular activating system is the pathway that transmits sensory information from the outside to the cerebrum, acting as a filter for what the brain should feel. It also acts as a stimulant to keep consciousness sharp. And anesthetics block the transmission of information to the reticular activating system. Anesthesia makes you unconscious or numb because no external stimuli can reach the brain and you can”t stay awake.
In order to explain in detail how to block the transmission of information to the reticular activating system, we must first understand how stimuli are transmitted along the nerves. Like all other cells, nerve cells have a membrane made up mainly of phospholipids, which are fat-soluble. They also have a very long shape compared to normal cells. Within a nerve cell, electrical impulses travel along the membrane and transmit signals. The transmission of signals between neighboring nerve cells occurs through the synapse, the space between neighboring nerve cells, where signal transmitters (chemicals) are secreted and then absorbed by the next cell. The release of these substances is regulated by ion channels in the cell membrane.
Anesthetics dissolve in the lipid layer of the cell membrane and increase the fluidity of the membrane, which changes the structure of the ion channels in the cell membrane. The flow of ions in and out of the membrane through the altered channels is less efficient, making the nerve cell less receptive to electrical impulses. This reduced ability of nerve cells to transmit impulses is called anesthesia.
Because they act on cell membranes, anesthetics are closely correlated with their fat solubility, and some of the most commonly used anesthetics in clinical practice today include Nitrous Oxide, Halothane, Ethrane, Forane, and newer ones such as Desflurane and Sevoflurane. Interestingly, these anesthetics are used selectively, depending on the individual patient’s condition and the nature of the surgery, and are constantly being researched to improve their effectiveness and safety.
It is unclear how anesthesia will evolve in the future, and there have been many recent cases of narcotic anesthetics such as propofol being misused as “milk injections,” so it is advisable to use them with caution. At the same time, it is expected that future anesthetics will become more sophisticated, and the safety and effectiveness of anesthesia will be further improved as personalized treatments for individual patients are developed.
