Continuous supraclavicular brachial plexus block using indwelling cannulae for prolonged analgesia of the upper extremity - abstract

ABSTRACT

The upper extremity has a specially organized innervation, the brachial plexus, which can be easily blocked by a supraclavicular approach. However, its use for prolonged intra-operative and post-operative analgesia has only been recently explored. The rising costs of general anaesthetic agents and the associated hospital stay, together with the desirability of reducing, or eliminating, the need for systemic narcotic analgesics, prompted us to investigate prolonged brachial plexus analgesia. The method is inexpensive, usually not technically difficult, as safe as conventional local anaesthesia and suitable for both emergency and elective cases. A pilot study on 10 healthy patients was carried out between June and November, 1987. Patients of either sex, from 14 to 47 years old, were included. The three-dimensional approach to the brachial plexus of McIntosh and Mushin, using an intravenous cannula, was employed throughout. After injecting an initial test dose of local anaesthetic, the cannula was left in-situ for further "top up" doses, through a suitable injection port. Xylocaine (1-2 percent) was used for the initial block and bupivacaine, (0.5 percent) for the post-operative maintenance of analgesia. The mean dose of xylocaine for surgical anaesthesia was 5.42 mg/kg body weight, and the mean duration of anaesthesia 137.8 minutes. The mean time lapse to the first "top up" dose was 225.4 minutes and the mean duration of effect to the 2nd "top up" dose 412.5 minutes. No patient required more than two post-operative doses. This pilot study appears to be sufficiently promising to warrant a more extensive trial of prolonged brachial plexus analgesia (AU)