Structures of general<unk> s widely used in medicine.1 - ethanol, 2 - chloroform, 3 - diethyl ether, 4 - fluroxene, 5 - halothane, 6 - methoxyflurane, 7 - enflurane, 8 - isoflurane, 9 - desflurane, 10 - sevoflurane A general<unk>  (or<unk>  is a drug that brings about a reversible loss of consciousness. These drugs are generally administered by an<unk> t/anesthesiologist in order to induce or maintain general anaesthesia to facilitate surgery. General<unk> s have been widely used in surgery since 1842 when Crawford Long for the first time administered diethyl ether to a patient and performed a painless operation. It has long been believed that general<unk> s exert their effects (analgesia, unconsciousness, immobility) by modulating the activity of membrane proteins in the neuronal membrane. However, the exact location and mechanism of this<unk>  are still largely unknown although much research has been done in this area. There are a number of<unk> , both outdated and modern, that attempt to explain<unk><unk> . The concept of specific interactions between receptors and drugs first introduced by Paul Ehrlich states that drugs<unk> ly when they are bound to their targets (receptors). However, this concept does not seem to apply perfectly in the case of general<unk> s, or at least to explain completely it's<unk> , because: * Molecular structures of general<unk> s widely used in medicine are very simple and diverse so that there is no obvious structure–activity relationship. * Most general<unk> s have remarkably weak affinity for their targets<unk> g at much higher concentrations than most other drugs so that diverse side effects are inevitable. All these common features of general<unk> s made it hard for early researchers to believe that general<unk> s act in a specific manner and their<unk>  on neuronal membrane was thought to be global (through nonspecific perturbation of lipid membrane of CNS neurons) rather than through specific sites.
Theories of general anaesthetic action
Instruments used in anesthesiology
Nomenclature of mechanical ventilation
Anesthesia awareness
Neural correlates of consciousness
Instruments used in general medicine
Instruments used in general surgery
Instruments used in obstetrics and gynecology