Halothane

Indications

Halothane is used for: Induction and maintenance of general anaesthesia

Adult Dose

Inhalation Induction and maintenance of general anaesthesia Adult: Induction: 0.5% v/v of halothane in oxygen or mixture of nitrous oxide and oxygen, increase gradually according to response to a concentration of 2-4% v/v. Maintenance: 0.5-2% v/v depending on the flow rate used.

Child Dose

Inhalation Induction and maintenance of general anaesthesia Child: Induction: 1.5-2% v/v. Maintenance: 0.5-1.5% v/v.

Renal Dose

Administration

Contra Indications

Known or suspected susceptibility to malignant hyperthermia, raised CSF pressure, history of unexplained jaundice or acute hepatic damage from previous exposure to halothane. Childn <18 yr undergoing outpatient dental surgery.

Precautions

Patient w/ phaeochromocytoma, myasthenia gravis, renal failure, pre-existing hepatic disease. Childn. Pregnancy and lactation. Patient Counselling May impair ability to drive or operate machinery. Monitoring Parameters Monitor pulse and BP.

Pregnancy-Lactation

Interactions

Increased risk of ventricular dysrhythmias w/ epinephrine. Increased risk of malignant hyperthermia w/ suxamethonium. Prolonged recovery from anaesth w/ concurrent use of ketamine for induction. May potentiate response to non-depolarising muscle relaxants, hypotensive agents (e.g. hexamethonium bromide, trimetaphan camsilate).

Adverse Effects

Side effects of Halothane : Post-op nausea, vomiting, and shivering; resp depression, hypotension, skeletal muscle relaxation, bradycardia. Potentially Fatal: Hepatotoxicity, malignant hyperthermia, cardiac arrhythmias.

Mechanism of Action

Halothane is a potent non-flammable inhalational anaesth which depresses both cerebral function and sympathetic activity. It suppresses salivary, bronchial and gastric secretions and dilates the bronchioles.