A comparison of ultrasound versus paresthesia technique for supraclavicular brachial plexus block

Abstract

Background: Ultrasonography is a newer tool for identification of nerves in the practice of regional anaesthesia. Visualization of target structures and spread of drugs under direct vision and thus avoiding complications like pneumothorax, accidental intravascular injections are potential benefit of ultrasonography technique. Aim of the study was to examine the usefulness of ultrasound guided brachial plexus block and compare it with paresthesia technique with the believe that ultrasound guidance can shorten the onset as well as increase the duration of blockade..Methods: Eighty patients of either sex, 18-60 years, posted for upper limb surgery were divided into 2 groups according to the technique used to give block, group US (ultrasound technique) and group PA (paresthesia technique). Both the groups received 0.5 % bupivacaine 20 ml with 8 mg of dexamethasone.Results: There was notable difference between the patient groups with regard to initiation of motor blockade (10 min group US vs 11.1 min group PA, p <0.0156) and sensory blockade (5.16 min group US vs 6.96 min group PA, p <0.0001) also duration of motor blockade (1272.88 min in group US vs 899.25 min in group PA, p <0.0001) and sensory blockade (1343.88 min in group US vs 996.75 min in group PA, p<0.0001).Conclusions: Ultrasound guided supraclavicular brachial plexus blocks result in a higher success rate with respect to onset and duration of blockade with less incidence of complications compared to paresthesia technique.