Author: Mrs. Saba Ruksaar
Volume: 01
First Online: 31 August 2024
Pages: 249-267
DOI:

General anesthetics are drugs that induce reversible loss of consciousness and sensation, used primarily during surgical procedures to ensure patients do not feel pain and remain unconscious. They are classified into inhalation anesthetics, intravenous anesthetics, and dissociative anesthetics. The mechanism of action typically involves enhancing inhibitory neurotransmission or inhibiting excitatory neurotransmission in the central nervous system, leading to altered synaptic transmission and loss of consciousness. Inhalation anesthetics like halothane, methoxyflurane, enflurane, sevoflurane, isoflurane, and desflurane are administered via the respiratory system and act by modulating the activity of ion channels such as GABA-A receptors and potassium channels, leading to decreased neuronal excitability. These agents are widely used due to their rapid onset and easy controllability of anesthesia depth. Ultra-short-acting barbiturates, such as methohexital sodium, thiamylal sodium, and thiopental sodium, are administered intravenously and induce anesthesia quickly by enhancing GABAergic inhibition. These agents are often used for induction of anesthesia due to their rapid onset and short duration of action. Dissociative anesthetics like ketamine hydrochloride induce a trance-like state with analgesia, amnesia, and sedation. Ketamine works by antagonizing NMDA receptors, providing both anesthesia and analgesia without significantly depressing respiratory function, making it valuable in emergency and pediatric anesthesia.