WHAT IS ANAESTHESIA? HOW DOES IT WORK?

Anaesthesiology is one of the highest paying jobs, with an average salary in the UK of £92,000, but what do anaesthesiologists actually do?

Every patient needing anaesthesia has a different dose given to them, with many factors being taken into consideration, such as: what type of surgery it is how long the surgery will take how old the patient is, etc

In order to take all of these factors into account, the anaesthesiologist comes up with an ‘anesthetic plan’, which typically includes pain control, amnesia (the patient doesn’t form any new memories), areflexia (the patient isn’t moving), and unconsciousness

There are three types of anaesthesia: regional, inhalation and intravenous Regional anaesthesia blocks pain signals (electrical impulses sent in the nervous system) from a specific part of the body from getting to the brain, by binding to the proteins in neurons’ cell membranes that let charged particles in and out, and allowing the flow of negatively charged ions into the cell, which then causes a build up of negative charge, thereby preventing the neuron from transmitting electrical signals. This means that regional anaesthetics only target one part of the body, rather than the whole body An example of a regional anaesthetic is cocaine, which was discovered by accident but is still occasionally used as an anaesthetic and has a similar chemical structure to regional anaesthetics

TInhalational anesthetics, however, work on the entire body including the brain to make you unconscious The way that these work is not completely understood, but they block the release of neurotransmitters. One of the first common inhalational anesthetics discovered in western medicine was diethyl ether, which at first was used recreationally until doctors realised that people didn’t notice injuries when under the influence. This led to the use of diethyl ether in dental extractions and surgeries in the 1840s

Usually inhalational anaesthesia is supplemented with intravenous anaesthesia, which was developed in the 1870s and includes sedatives like propofol, which causes unconsciousness, and opioids like fentanyl, which reduce pain. Intravenous anaesthesia affects the electrical signals in nervous systems and prevents certain parts of the brain from communicating with each other, causing unconsciousness; however there is a lot we still don’t know about how intravenous anaesthesias stop these parts of the brain from communicating.

One of the most famous inhalational gases, nitrous oxide, was discovered by a man named Humphrey Davy while working at the Pneumatic Institution in 1798, where he tested on himself the effects of inhaling this gas. He noticed the euphoric effect, making him laugh, and the fact that it alleviated the pain of his toothache He suggested the nitrous oxide could be used as an anaesthetic during surgery, but the medical community decided against this Instead, ‘laughing gas’ (as he called it) caught the public’s attention and gas inhaling ‘parties’ began. However, although Humphrey Davy’s work was dismissed in his time, it is still used in anaesthesia today.

Anaesthetics have a long history that can be traced back to many different regions, including the Babylonians, Greeks, Chinese and Incas During this time, all kinds of substances were tried out as anaesthetics, including alcohol, the opium poppy, cannabis, cocaine, and common poisons like hemlock and aconite. For example, the Incas used chewed coca leaves in the wound during trephination (bone or skull surgery), but it wasn’t until 1855 that cocaine was isolated from the coca plant and used as a local anaesthetic. However, if we move to the other side of the world, in the Sushruta Samhita (the ancient Indian medical text), the use of wine with incense of Indian hemp was advocated as a surgical sedative

Although there is still a lot to understand about anaesthesia, it’s importance in medicine has been made apparent, with many now-common practices having been enabled by anaesthetics, such as performing csections, replacing blocked arteries, damaged livers and kidneys, and many other life-saving operations

Every year, new anaesthesia techniques are developed, which is what makes anaesthesiology so interesting