halotaani

Halotaani, commonly known in English as halothane, is a volatile, halogenated hydrocarbon used as a general inhalation anesthetic. It is a colorless liquid at room temperature with a faint sweet odor. Its chemical name is 2-bromo-2-chloro-1,1,1-trifluoroethane, and its formula is C2HBrClF3. It is administered by inhalation through a vapourizer, usually in a mixture with oxygen or air and sometimes nitrous oxide. Halotaani has relatively high lipid solubility; the blood–gas partition coefficient is about 2.3, and the oil–gas partition coefficient is high, contributing to slower induction and emergence compared with some newer agents. The minimum alveolar concentration (MAC) in adults is about 0.75%.

Pharmacology: The precise mechanism of action is not fully understood, but halotaani is believed to act on multiple central nervous system targets, including enhancing GABA-A receptor activity and inhibiting excitatory receptors, producing anesthesia and amnesia.

Medical use and history: Introduced in the 1950s, halotaani became widely used for induction and maintenance of anesthesia. Its use has declined in many countries due to concerns about hepatotoxicity and the development of newer agents with faster recovery and better safety profiles.

Safety and adverse effects: Halotaani can depress respiration and cardiovascular function. It is associated with rare but serious halothane hepatitis, a potentially fatal liver injury. It can sensitize the myocardium to catecholamines, raising the risk of arrhythmias; malignant hyperthermia is a rare risk with all volatile anesthetics. Because of these risks, monitoring and readiness to manage airway, breathing, and circulation are essential.

See also: isofluraane, sevofluraane, desfluraane.