title: Latency of brachial plexus block. The effect on onset time of warming local anaesthetic solutions.
abstract: A double-blind study was set up to investigate the effect of warming local anaesthetic solutions on the latency of onset of subclavian perivascular brachial plexus blocks. Twenty-four adult patients were randomly allocated into two equal groups. In group A the local anaesthetic was injected at room temperature, while in group B the local anaesthetic solution was prewarmed to 37 degrees C in a thermostatically controlled heating block. All blocks were performed using 0.5 ml/kg of a solution prepared by mixing equal volumes of 0.5% bupivacaine with adrenaline 1:200,000, and 1% prilocaine. The speed of onset of sensory blockade was significantly increased when the temperature of the local anaesthetic solution was increased to 37 degrees C. There were no adverse side effects in either group.
authors.affiliation: Department of Anaesthetics, Addenbrooke's Hospital, Cambridge.
authors.forename: P J
authors.initials: PJ
authors.lastname: Heath
authors.forename: G S
authors.initials: GS
authors.lastname: Brownlie
authors.forename: M J
authors.initials: MJ
authors.lastname: Herrick
mesh_terms: D000779:Anesthetics, Local / Q000008:administration & dosage / Q000494:pharmacology*; D001917:Brachial Plexus / Q000187:drug effects; D004311:Double-Blind Method; D005260:Female; D006358:Hot Temperature; D006801:Humans; D008297:Male; D008875:Middle Aged; D009046:Motor Neurons / Q000187:drug effects; D009407:Nerve Block; D009475:Neurons, Afferent / Q000187:drug effects; D011897:Random Allocation; D013997:Time Factors
chemical_list: D000779:Anesthetics, Local