Anaesthetics
INTRODUCTION
The word "anesthesia", coined by Oliver Wendell Holmes, Sr. (1809–1894) in 1846 from the Greek αν-, an-, "without"; and aisthēsis, "sensation"), refers to the inhibition of sensation. An anesthetic (American English) (or anaesthetic, (Commonwealth English)) is a drug that causes anesthesia—reversible loss of sensation. They contrast with analgesics (painkillers), which relieve pain without eliminating sensation. These drugs are generally administered to facilitate surgery. A wide variety of drugs are used in modern anesthetic practice. Many are rarely used outside of anesthesia, although others are used commonly by all disciplines.
Anesthetics are categorized into two classes: general anesthetics, which cause a reversible loss of consciousness, and local anesthetics, which cause a reversible loss of sensation for a limited region of the body while maintaining consciousness. Combinations of anesthetics are sometimes used for their synergistic and additive therapeutic effects. Adverse effects, however, may also be increased.
TYPES OF ANAESTHETICS
* Local anesthetics
A local anesthetic (LA) is a drug that causes reversible local anesthesia, generally for the aim of having a local analgesic effect, that is, inducing absence of pain sensation, although other local senses are often affected as well. Also, when it is used on specific nerve pathways (nerve block), paralysis (loss of muscle power) can be achieved as well.
Clinical local anesthetics belong to one of two classes: * Amino amide local anesthetics, and * Amino ester local anesthetics.
Synthetic local anesthetics are structurally related to cocaine. They differ from cocaine mainly in that they have no abuse potential and do not act on the sympathoadrenergic system, i.e. they do not produce hypertension or local vasoconstriction, with the exception of Ropivacaine and Mepivacaine that do produce weak vasoconstriction.
Local anesthetics vary in their pharmacological
The word "anesthesia", coined by Oliver Wendell Holmes, Sr. (1809–1894) in 1846 from the Greek αν-, an-, "without"; and aisthēsis, "sensation"), refers to the inhibition of sensation. An anesthetic (American English) (or anaesthetic, (Commonwealth English)) is a drug that causes anesthesia—reversible loss of sensation. They contrast with analgesics (painkillers), which relieve pain without eliminating sensation. These drugs are generally administered to facilitate surgery. A wide variety of drugs are used in modern anesthetic practice. Many are rarely used outside of anesthesia, although others are used commonly by all disciplines.
Anesthetics are categorized into two classes: general anesthetics, which cause a reversible loss of consciousness, and local anesthetics, which cause a reversible loss of sensation for a limited region of the body while maintaining consciousness. Combinations of anesthetics are sometimes used for their synergistic and additive therapeutic effects. Adverse effects, however, may also be increased.
TYPES OF ANAESTHETICS
* Local anesthetics
A local anesthetic (LA) is a drug that causes reversible local anesthesia, generally for the aim of having a local analgesic effect, that is, inducing absence of pain sensation, although other local senses are often affected as well. Also, when it is used on specific nerve pathways (nerve block), paralysis (loss of muscle power) can be achieved as well.
Clinical local anesthetics belong to one of two classes: * Amino amide local anesthetics, and * Amino ester local anesthetics.
Synthetic local anesthetics are structurally related to cocaine. They differ from cocaine mainly in that they have no abuse potential and do not act on the sympathoadrenergic system, i.e. they do not produce hypertension or local vasoconstriction, with the exception of Ropivacaine and Mepivacaine that do produce weak vasoconstriction.
Local anesthetics vary in their pharmacological
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