Anesthesia

Anesthesia a condition of temporary loss of sensation or consciousness induced for medical purposes, allowing pain prevention or release from pain, amnesia, relaxation of muscles, and unconsciousness. Anesthesia enables the painless act of medical procedures that would otherwise cause severe or unbearable pain or are not feasible technically.

There are three broad categories of anesthesia (i) General anesthesia, a condition usually caused either by injected or inhaled drugs; in which a controlled unconsciousness results, one feels nothing, due to suppressed central nervous system activity, mostly used in major operations on the heart, lungs or in the abdomen, and many operations on the brain or the major arteries. (ii) A local anesthesia, a small part of the body is numbed and can be done easily by injections, sprays, ointments, or drops; the patient stays conscious and pain-free. Familiar examples are anesthetizing a tooth for dental work and some regular eye operations; (iii) Sedation, a 'sleep-like' state, feeling drowsy and relaxed about what is happening, inhibiting anxiety, suppresses the central nervous system to a lesser extent, and resulting long-term memory without creating unconsciousness. For a particular patient’s medical procedure and to achieve the types and degree of anesthesia, the clinician chooses one or more characteristics of drugs and appropriate procedures. The procedures and drugs used include local anesthetics, general anesthetics, sedatives, hypnotics, analgesics, neuromuscular blocking drugs, etc.

A patient's medical history, such as genetic disorders, chronic and any coexisting diseases, particularly respiratory and cardiac diseases, might impact the anesthetic. In addition, the surgical procedure's complexity, the patient's age, and particular factors linked to the medical procedures must be considered for anesthesia, eg, anesthesia in childbirth must consider not only the mother but the baby. [Mamun Rashid Chowdhury]