What is the difference between local and general anesthesia?

Anesthesia is roughly divided into local and general anesthesia. Local anesthesia is applied for small regions including the surgical region. General anesthesia induces an anesthetic condition throughout the whole body, and it is applicable for surgery of any region.

For local anesthesia, local anesthetics are injected into the surgical site or an area near nerves transmitting pain stimulation from the surgical and injected regions. For general anesthesia, inhalant anesthetics and intravenous drugs are used in various combinations.

Generally, local anesthesia is given for small surgeries, and general anesthesia for abdominal, thoracic, and brain surgeries. For junior high school students and younger children, general anesthesia is usually applied, excluding surgery for small injuries.

For surgery for diseases in regions lower than the navel (gynecological diseases, appendicitis, hemorrhoids, and lower limb fractures), local spinal anesthesia (anesthesia of the lower half of the body by injection into the lower back) is employed.

Patients can sleep during local anesthesia by intravenous injection of a sleep-inducing drug. In continuous epidural anesthesia, a thin tube is placed near the target nerve(s) via a dorsal site corresponding to the surgical region, and local anesthetics are continuously or intermittently infused. Since anesthetics can be injected through the tube even after surgery, this procedure is useful for analgesic treatment after surgery. For surgery of regions lower than the neck, combination with general anesthesia is common.