Anesthesia was developed in order to block or prevent pain during medical procedures. Anesthesia has been the backbone of the medical world for around 100 years now. Early anesthetics were primitive and many patients simply did not trust anesthetics. Anesthesia is still a risky process even in todays advanced medical world. Anesthesia is not used to treat or diagnose any specific disease; the sole purpose is to aid both the patient and surgeon through procedures. However, anesthesia is used in different ways based on the magnitude of the procedure. There are three levels of anesthesia which include; local, regional, and general anesthesia. An anesthesiologist determines which type of anesthesia will be needed.
Local anesthesia is used for minor procedures and is the safest of the three types of anesthesia.  The main objective of this anesthetic is to block pain in a small region of the body. An example of a procedure where a local anesthetic could be used is when a patient has a large gouge in their skin and stitches are required to heal the patient. Regional anesthetics are used to block a larger specific region of the body. A patient would be induced with a regional anesthetic during a caesarean surgery or if an operation needed to be conducted on a limb of the body.  General anesthesia is the most dangerous and powerful of the three. When a patient is undergoing an operation such as heart surgery they would be put unconscious for the duration of the surgery by a general anesthetic.
There is no difference between local and regional anesthetics. They only differ in the way they are injected. For local anesthesia, a shot of a local anesthetic is injected around the surgical area. For example, if a patient needed to be stitched, a few shots of local anesthetics would be injected around the wound before the doctor started to insert stiches. For regional anesthesia, a local anesthetic will be injected into a nerve. The anesthetic will then affect a series of nerves. The anesthetic blocks pain by interrupting nerve transmissions, also known as action potentials. Action potentials occur at a constant rate within the body. Action potentials occur between nerve cells and all the body to feel pain.
A nerve cell has a negative charge at a resting state due to negatively charged proteins within the cell. Although the inside of the cell contains positively charged potassium ions as well, overall the charge is still negative. Along with potassium on the inside of the cell, positively charged sodium ions are located around the exterior of the cell. When an action potential occurs, the cell becomes even more negatively charged. In turn, this causes sodium transport molecules in the membrane of the cell to open. Sodium will then enter the cell during active transport. The positively charged sodium will cancel out the negatively charged active potential which will depolarize the cell. This allows...